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Neuroscience has convinced people that much of their behavior is determined by causes unknown to them and beyond their control. However, are advances in neuroscience truly a prerequisite for such beliefs? Robert Kane's theory of ultimate responsibility is libertarian theory. Its innovative nature makes it possible to discuss the neurophysiological basis of its postulates. Using the functions of the midbrain dopaminergic system as an example, this article provides an overview of this neurophysiological basis. According to Kane, if we are to be ultimately responsible for our wills as well as for our actions, some actions in our lives must lack sufficient motives and causes. These are self-forming actions. Dopamine is hypothesized to mediate self-forming action execution. Dopamine not only mediates action but also ensures synaptic plasticity in the brain, that is, learning from action; hence, dopamine changes the acting individual and provides the formation of our own wills. The basal ganglia, which are the main target of dopamine in the brain, act through parallel pathways and are involved in decision-making processes. Dopamine is also involved in the regulation of the neurodynamical properties of prefrontal cortex networks with random spiking noise. It can be assumed that the activity of the dopaminergic system is closely related to the physiological basis of free will., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The implementation of low-dimensional movement control by the central nervous system has been debated for decades. In this study, we investigated the dimensionality of the control signals received by spinal motor neurons when controlling either the ankle or knee joint torque. We first identified the low-dimensional latent factors underlying motor unit activity during torque-matched isometric contractions in male participants. Subsequently, we evaluated the extent to which motor units could be independently controlled. To this aim, we used an online control paradigm in which participants received the corresponding motor unit firing rates as visual feedback. We identified two main latent factors, regardless of the muscle group (vastus lateralis-medialis and gastrocnemius lateralis-medialis). The motor units of the gastrocnemius lateralis could be controlled largely independently from those of the gastrocnemius medialis during ankle plantarflexion. This dissociation of motor unit activity imposed similar behavior to the motor units that were not displayed in the feedback. Conversely, it was not possible to dissociate the activity of the motor units between the vastus lateralis and medialis muscles during the knee extension tasks. These results demonstrate that the number of latent factors estimated from linear dimensionality reduction algorithms does not necessarily reflect the dimensionality of volitional control of motor units. Overall, individual motor units were never controlled independently of all others but rather belonged to synergistic groups. Together, these findings provide evidence for a low-dimensional control of motor units constrained by common inputs, with notable differences between muscle groups., Competing Interests: The authors declare no competing financial interests., (Copyright © 2024 the authors.)

Little is known about the electrophysiologic activity of the intact human spinal cord during volitional movement. We analyzed epidural spinal recordings from a total of five human subjects of both sexes during a variety of upper extremity movements and found that these spinal epidural electrograms contain spectral information distinguishing periods of movement, rest, and sensation. Cervical epidural electrograms also contained spectral changes time-locked with movement. We found that these changes were primarily associated with increased power in the theta (4-8 Hz) band and feature increased theta phase to gamma amplitude coupling, and this increase in theta power can be used to topographically map distinct upper extremity movements onto the cervical spinal cord in accordance with established myotome maps of the upper extremity. Our findings have implications for the development of neurostimulation protocols and devices focused on motor rehabilitation for the upper extremity, and the approach presented here may facilitate spatiotemporal mapping of naturalistic movements., Competing Interests: The authors declare no competing financial interests., (Copyright © 2024 the authors.)

Volitional modulation of neural activity is not confined to the cortex but extends to various brain regions. Yet, it remains unclear whether neurons in the basal ganglia structure, the external globus pallidus (GPe), can be volitionally controlled. Here, we employed a volitional conditioning task to compare the volitional modulation of GPe and primary motor cortex (M1) neurons as well as the underlying circuits and control mechanisms. The results revealed that the volitional modulation of GPe neuronal activity engaged both M1 and substantia nigra pars reticulata (SNr) neurons, indicating the involvement of the cortex-GPe-SNr loop. In contrast, the volitional modulation of M1 neurons primarily occurred through the engagement of M1 local circuitry. Furthermore, lesioning M1 neurons did not affect the volitional learning or volitional control signal in GPe, whereas lesioning of GPe neurons impaired the learning process for the volitional modulation of M1 neuronal activity at the intermediate stage. Additionally, lesion of GPe neurons enhanced M1 neuronal activity when performing the volitional control task without reward delivery and a random reward test. Taken together, our findings demonstrated that GPe neurons could be volitionally controlled by engagement of the cortical-basal ganglia circuit and inhibit learning process for the volitional modulation of M1 neuronal activity by regulating M1 neuronal activity. Thus, GPe neurons can be effectively harnessed for independent volitional modulation for neurorehabilitation in patients with cortical damage. KEY POINTS: The cortical-basal ganglia circuit contributes to the volitional modulation of GPe neurons. Volitional modulation of M1 neuronal activity mainly engages M1 local circuitry. Bilateral GPe lesioning impedes volitional learning at the intermediate stages. Lesioning of GPe neurons inhibits volitional learning process by regulating M1 neuronal activity., (© 2024 The Authors. The Journal of Physiology © 2024 The Physiological Society.)

The intentional binding effect refers to the phenomenon where the perceived temporal interval between a voluntary action and its sensory consequence is subjectively compressed. Prior research revealed the importance of tactile feedback from the keyboard on this effect. Here we examined the necessity of such tactile feedback by utilizing a touch-free key-press device without haptic feedback, and explored how initial/outcome sensory modalities (visual/auditory/tactile) and their consistency influence the intentional binding effect. Participants estimated three delay lengths (250, 550, or 850 ms) between the initial and outcome stimuli. Results showed that regardless of the combinations of sensory modalities between the initial and the outcome stimuli (i.e., modal consistency), the intentional binding effect was only observed in the 250 ms delay condition. This findings indicate a stable intentional binding effect both within and across sensory modalities, supporting the existence of a shared mechanism underlying the binding effect in touch-free voluntary actions., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Debates about the concept of Free Will date back to ancient times. About 40 years ago, Benjamin Libet designed an experiment showing that the conscious intention to move is preceded by a specific pattern of brain activation. His finding suggested that unconscious processes determine our decisions. Libet-style experiments have continued to dominate the debate about Free Will, pushing some authors to argue that the existence of Free Will is a mere illusion. We believe that this dispute is because we often measure Free Will using arbitrary human decisions rather than deliberate actions. After reviewing the definition of Free Will and the related literature, we conclude that the scientific evidence does not disprove the existence of Free Will. However, our will encounters several constraints and limitations that should be considered when evaluating our deeds' personal responsibility., (© 2023. Fondazione Società Italiana di Neurologia.)

It has been shown that cognitive performance could be improved by expressing volition (e.g., making voluntary choices), which necessarily involves the execution of action through a certain effector. However, it is unclear if the benefit of expressing volition can generalize across different effectors. In the present study, participants made a choice between two pictures either voluntarily or forcibly, and subsequently completed a visual search task with the chosen picture as a task-irrelevant background. The effector for choosing a picture could be the hand (pressing a key), foot (pedaling), mouth (commanding), or eye (gazing), whereas the effector for responding to the search target was always the hand. Results showed that participants responded faster and had a more liberal response criterion in the search task after a voluntary choice (vs. a forced choice). Importantly, the improved performance was observed regardless of which effector was used in making the choice, and regardless of whether the effector for making choices was the same as or different from the effector for responding to the search target. Eye-movement data for oculomotor choice showed that the main contributor to the facilitatory effect of voluntary choice was the post-search time in the visual search task (i.e., the time spent on processes after the target was found, such as response selection and execution). These results suggest that the expression of volition may involve the motor control system in which the effector-general, high-level processing of the goal of the voluntary action plays a key role., (© 2023. The Psychonomic Society, Inc.)

The neuroscience of volition is an emerging subfield of the brain sciences, with hundreds of papers on the role of consciousness in action formation published each year. This makes the state-of-the-art in the discipline poorly accessible to newcomers and difficult to follow even for experts in the field. Here we provide a comprehensive summary of research in this field since its inception that will be useful to both groups. We also discuss important ideas that have received little coverage in the literature so far. We systematically reviewed a set of 2220 publications, with detailed consideration of almost 500 of the most relevant papers. We provide a thorough introduction to the seminal work of Benjamin Libet from the 1960s to 1980s. We also discuss common criticisms of Libet's method, including temporal introspection, the interpretation of the assumed physiological correlates of volition, and various conceptual issues. We conclude with recent advances and potential future directions in the field, highlighting modern methodological approaches to volition, as well as important recent findings., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The hippocampus is critical for recollecting and imagining experiences. This is believed to involve voluntarily drawing from hippocampal memory representations of people, events, and places, including maplike representations of familiar environments. However, whether representations in such "cognitive maps" can be volitionally accessed is unknown. We developed a brain-machine interface to test whether rats can do so by controlling their hippocampal activity in a flexible, goal-directed, and model-based manner. We found that rats can efficiently navigate or direct objects to arbitrary goal locations within a virtual reality arena solely by activating and sustaining appropriate hippocampal representations of remote places. This provides insight into the mechanisms underlying episodic memory recall, mental simulation and planning, and imagination and opens up possibilities for high-level neural prosthetics that use hippocampal representations.

A brain-machine interface demonstrates volitional control of hippocampal activity.

In 1983 Benjamin Libet and colleagues published a paper apparently challenging the view that the conscious intention to move precedes the brain's preparation for movement. The experiment initiated debates about the nature of intention, the neurophysiology of movement, and philosophical and legal understanding of free will and moral responsibility. Here we review the concept of "conscious intention" and attempts to measure its timing. Scalp electroencephalographic activity prior to movement, the Bereitschaftspotential, clearly begins prior to the reported onset of conscious intent. However, the interpretation of this finding remains controversial. Numerous studies show that the Libet method for determining intent, W time, is not accurate and may be misleading. We conclude that intention has many different aspects, and although we now understand much more about how the brain makes movements, identifying the time of conscious intention is still elusive., (Published by Elsevier Ltd.)

Studies of voluntary visual spatial attention have used attention-directing cues, such as arrows, to induce or instruct observers to focus selective attention on relevant locations in visual space to detect or discriminate subsequent target stimuli. In everyday vision, however, voluntary attention is influenced by a host of factors, most of which are quite different from the laboratory paradigms that use attention-directing cues. These factors include priming, experience, reward, meaning, motivations, and high-level behavioral goals. Attention that is endogenously directed in the absence of external attention-directing cues has been referred to as "self-initiated attention" or, as in our prior work, as "willed attention" where volunteers decide where to attend in response to a prompt to do so. Here, we used a novel paradigm that eliminated external influences (i.e., attention-directing cues and prompts) about where and/or when spatial attention should be directed. Using machine learning decoding methods, we showed that the well known lateralization of EEG alpha power during spatial attention was also present during purely self-generated attention. By eliminating explicit cues or prompts that affect the allocation of voluntary attention, this work advances our understanding of the neural correlates of attentional control and provides steps toward the development of EEG-based brain-computer interfaces that tap into human intentions., Competing Interests: The authors declare no competing financial interests., (Copyright © 2023 Nadra et al.)

Gaze following is a major element of non-verbal communication and important for successful social interactions. Human gaze following is a fast and almost reflex-like behaviour, yet it can be volitionally controlled and suppressed to some extent if inappropriate or unnecessary, given the social context. In order to identify the neural basis of the cognitive control of gaze following, we carried out an event-related fMRI experiment, in which human subjects' eye movements were tracked while they were exposed to gaze cues in two distinct contexts: A baseline gaze following condition in which subjects were instructed to use gaze cues to shift their attention to a gazed-at spatial target and a control condition in which the subjects were required to ignore the gaze cue and instead to shift their attention to a distinct spatial target to be selected based on a colour mapping rule, requiring the suppression of gaze following. We could identify a suppression-related blood-oxygen-level-dependent (BOLD) response in a frontoparietal network comprising dorsolateral prefrontal cortex (dlPFC), orbitofrontal cortex (OFC), the anterior insula, precuneus, and posterior parietal cortex (PPC). These findings suggest that overexcitation of frontoparietal circuits in turn suppressing the gaze following patch might be a potential cause of gaze following deficits in clinical populations., (© 2023 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)

Volition - the sense of control or agency over one's voluntary actions - is widely recognized as the basis of both human subjective experience and natural behavior in nonhuman animals. Several human studies have found peaks in neural activity preceding voluntary actions, for example the readiness potential (RP), and some have shown upcoming actions could be decoded even before awareness. Others propose that random processes underlie and explain pre-movement neural activity. Here, we seek to address these issues by evaluating whether pre-movement neural activity in mice contains structure beyond that present in random neural activity. Implementing a self-initiated water-rewarded lever-pull paradigm in mice while recording widefield [Ca++] neural activity we find that cortical activity changes in variance seconds prior to movement and that upcoming lever pulls could be predicted between 3 and 5 s (or more in some cases) prior to movement. We found inhibition of motor cortex starting at approximately 5 s prior to lever pulls and activation of motor cortex starting at approximately 2 s prior to a random unrewarded left limb movement. We show that mice, like humans, are biased toward commencing self-initiated actions during specific phases of neural activity but that the pre-movement neural code changes over time in some mice and is widely distributed as behavior prediction improved when using all vs. single cortical areas. These findings support the presence of structured multi-second neural dynamics preceding self-initiated action beyond that expected from random processes. Our results also suggest that neural mechanisms underlying self-initiated action could be preserved between mice and humans., Competing Interests: CM, YZ, YS, JB, FB, NS, GS, SS, TM No competing interests declared, (© 2022, Mitelut et al.)

Correlated activity of neurons can lead to long-term strengthening or weakening of the connections between them. In addition, the behavioral context, imparted by execution of physical movements or the presence of a reward, can modulate the plasticity induced by Hebbian mechanisms. In the present study, we have combined behavior and induced neuronal correlations to strengthen connections in the motor cortex of adult behaving monkeys. Correlated activity was induced using an electrical-conditioning protocol in which stimuli gated by voluntary movements were used to produce coactivation of neurons at motor-cortical sites involved in those movements. Delivery of movement-dependent stimulation resulted in small increases in the strength of associated cortical connections immediately after conditioning. Remarkably, when paired with further repetition of the movements that gated the conditioning stimuli, there were substantially larger gains in the strength of cortical connections, which occurred in a use-dependent manner, without delivery of additional conditioning stimulation. In the absence of such movements, little change was observed in the strength of motor-cortical connections. Performance of the motor behavior in the absence of conditioning also did not produce any changes in connectivity. Our results show that combining movement-gated stimulation with further natural use of the "conditioned" pathways after stimulation ends can produce use-dependent strengthening of connections in adult primates, highlighting an important role for behavior in cortical plasticity. Our data also provide strong support for combining movement-gated stimulation with use-dependent physical rehabilitation for strengthening connections weakened by a stroke or spinal cord injury.

Memory recollections and voluntary actions are often perceived as spontaneously generated irrespective of external stimuli. Although products of our neurons, they are only rarely accessible in humans at the neuronal level. Here I review insights gleaned from unique neurosurgical opportunities to record and stimulate single-neuron activity in people who can declare their thoughts, memories and wishes. I discuss evidence that the subjective experience of human recollection and that of voluntary action arise from the activity of two internal neuronal generators, the former from medial temporal lobe reactivation and the latter from frontoparietal preactivation. I characterize properties of these generators and their interaction, enabling flexible recruitment of memory-based choices for action as well as recruitment of action-based plans for the representation of conceptual knowledge in memories. Both internal generators operate on surprisingly explicit but different neuronal codes, which appear to arise with distinct single-neuron activity, often observed before participants' reports of conscious awareness. I discuss prediction of behaviour based on these codes, and the potential for their modulation. The prospects of editing human memories and volitions by enhancement, inception or deletion of specific, selected content raise therapeutic possibilities and ethical concerns., (© 2021. Springer Nature Limited.)

Brain-machine interfaces allow neuroscientists to causally link specific neural activity patterns to a particular behaviour. Thus, in addition to their current clinical applications, brain-machine interfaces can also be used as a tool to investigate neural mechanisms of learning and plasticity in the brain. Decades of research using such brain-machine interfaces have shown that animals (non-human primates and rodents) can be operantly conditioned to self-regulate neural activity in various motor-related structures of the brain. Here, we ask whether the human brain, a complex interconnected structure of over 80 billion neurons, can learn to control itself at the most elemental scale-a single neuron. We used the unique opportunity to record single units in 11 individuals with epilepsy to explore whether the firing rate of a single (direct) neuron in limbic and other memory-related brain structures can be brought under volitional control. To do this, we developed a visual neurofeedback task in which participants were trained to move a block on a screen by modulating the activity of an arbitrarily selected neuron from their brain. Remarkably, participants were able to volitionally modulate the firing rate of the direct neuron in these previously uninvestigated structures. We found that a subset of participants (learners), were able to improve their performance within a single training session. Successful learning was characterized by (i) highly specific modulation of the direct neuron (demonstrated by significantly increased firing rates and burst frequency); (ii) a simultaneous decorrelation of the activity of the direct neuron from the neighbouring neurons; and (iii) robust phase-locking of the direct neuron to local alpha/beta-frequency oscillations, which may provide some insights in to the potential neural mechanisms that facilitate this type of learning. Volitional control of neuronal activity in mnemonic structures may provide new ways of probing the function and plasticity of human memory without exogenous stimulation. Furthermore, self-regulation of neural activity in these brain regions may provide an avenue for the development of novel neuroprosthetics for the treatment of neurological conditions that are commonly associated with pathological activity in these brain structures, such as medically refractory epilepsy., (© The Author(s) (2021). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Background: The aim of this study was to investigate differences in reflexive and volitional cough airflows in advanced stage head and neck cancer survivors as it relates to aspiration status and time since treatment. The hypothesis is that those who aspirate several years after treatment completion would demonstrate reduced airflows for all cough parameters compared to those recently status post treatment completion given the known progressive deterioration associated with radiotherapy., Methods: Demographic and airflow data during both reflexive and volitional cough tasks and aspiration status as determined during fiberoptic endoscopic evaluation of swallow function were collected from 33 Head and Neck Cancer (HNC) survivors., Results: Omnibus MANOVA for dependent airflow variables and independent variables aspiration status, time since treatment and cough type (reflex or volitional) was significant (F(3,1) = 184, p < 0.000) indicating that peak expiratory flow rates (PEFR) were reduced under reflex (mean PEFR 1.88 SD 0.7) versus volitional (mean PEFR 2.3, SD 0.7) cough types; reduced for aspirators versus non-aspirators (F(2,1) = 4.1, p = 0.04) and reduced for those in the subacute versus chronic phase status post Intensity Modulated Radiotherapy (IMRT) (F(2,1) = 10.05, p = 0.002)., Conclusion: Findings of reduced reflexive compared to volitional cough airflows in head and neck cancer survivors are consistent with those from both healthy and other diseased populations. Additional findings that aspirators demonstrate reduced cough airflows compared to non-aspirators supports the hypothesis. Surprisingly, those recently status post treatment completion show worse cough airflows compared to those remotely status post treatment completion., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The dorso-posterior parietal cortex (DPPC) is a major node of the grasp/manipulation control network. It is assumed to act as an optimal forward estimator that continuously integrates efferent outflows and afferent inflows to modulate the ongoing motor command. In agreement with this view, a recent per-operative study, in humans, identified functional sites within DPPC that: (i) instantly disrupt hand movements when electrically stimulated; (ii) receive short-latency somatosensory afferences from intrinsic hand muscles. Based on these results, it was speculated that DPPC is part of a rapid grasp control loop that receives direct inputs from the hand-territory of the primary somatosensory cortex (S1) and sends direct projections to the hand-territory of the primary motor cortex (M1). However, evidence supporting this hypothesis is weak and partial. To date, projections from DPPC to M1 grasp zone have been identified in monkeys and have been postulated to exist in humans based on clinical and transcranial magnetic studies. This work uses diffusion-MRI tractography in two samples of right- (n = 50) and left-handed (n = 25) subjects randomly selected from the Human Connectome Project. It aims to determine whether direct connections exist between DPPC and the hand control sectors of the primary sensorimotor regions. The parietal region of interest, related to hand control (hereafter designated DPPC hand ), was defined permissively as the 95% confidence area of the parietal sites that were found to disrupt hand movements in the previously evoked per-operative study. In both hemispheres, irrespective of handedness, we found dense ipsilateral connections between a restricted part of DPPC hand and focal sectors within the pre and postcentral gyrus. These sectors, corresponding to the hand territories of M1 and S1, targeted the same parietal zone (spatial overlap > 92%). As a sensitivity control, we searched for potential connections between the angular gyrus (AG) and the pre and postcentral regions. No robust pathways were found. Streamline densities identified using AG as the starting seed represented less than 5 % of the streamline densities identified from DPPC hand . Together, these results support the existence of a direct sensory-parietal-motor loop suited for fast manual control and more generally, for any task requiring rapid integration of distal sensorimotor signals., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2021. Published by Elsevier Inc.)

Magicians' forcing techniques allow them to covertly influence spectators' choices. We used a type of force (Position Force) to investigate whether explicitly informing people that they are making a decision results in more deliberate decisions. The magician placed four face-down cards on the table in a horizontal row, after which the spectator was asked to select a card by pushing it forward. According to magicians and position effects literature, people should be more likely to choose a card in the third position from their left, because it can be easily reached. We manipulated whether participants were reminded that they were making a decision (explicit choice) or not (implicit choice) when asked to select one of the cards. Two experiments confirmed the efficiency of the Position Force-52% of participants chose the target card. Explicitly informing participants of the decision impairs the success of the force, leading to a more deliberate choice. A range of awareness measures illustrates that participants were unaware of their stereotypical behaviours. Participants who chose the target card significantly underestimated the number of people who would have chosen the same card, and felt as free as the participants who chose another card. Finally, we tested an embodied-cognition idea, but our data suggest that different ways of holding an object do not affect the level of self-control they have over their actions. Results are discussed in terms of theoretical implications regarding free will, Wegner's apparent mental causation, choice blindness and reachability effects.

The purpose of this study was to validate the Volition in Exercise Questionnaire in Italian language (VEQ-I). The translation and cultural adaptation of the VEQ-I was conducted using the forward-backward translation method. VEQ-I eighteen items correspond to the six-factors structure of the original version. The construct validity was verified by the confirmatory factor analysis (CFA) (CFI = 0.960; TLI = 0.943; RMSEA = 0.039; and SRMR = 0.040). The eighteen items were well distributed in six subscales and the six-factors structure of the questionnaire was supported. Internal Consistency value of the questionnaire was investigated for each subscale of the VEQ-I. Cronbach's alpha and Omega values of the Reasons, Postponing Training, Unrelated Thoughts, Self-Confidence, Approval from Others and Coping with Failure subscales were 0.76 (α) and 0.76 (ω), 0.76 (α) and 0.76 (ω), 0.87 (α) and 0.88 (ω), 0.85 (α) and 0.85 (ω), 0.70 (α) and 0.72 (ω) and 0.74 (α) and 0.74 (ω), respectively. They were acceptable in all the six subscales. The concurrent validity was assessed using the correlation among the subscales of VEQ-I measures and those contained in two questionnaires: Psychobiosocial States in Physical Education (PBS-SPE) and Exercise Motivations Inventory (EMI-2)., Competing Interests: The authors have declared that no competing interests exist.

Objective . Volitional modulation of single cortical neurons holds great potential for the implementation of brain-machine interfaces (BMIs) because it can induce a rapid acquisition of arbitrary associations between machines and neural activity. It can also be used as a framework to study the limits of single-neuron control in BMIs. Approach . We tested the control of a one-dimensional actuator in two BMI tasks which differed only in the neural contingency that determined when a reward was dispensed. A thresholded activity task, commonly implemented in single-neuron BMI control, consisted of reaching or exceeding a neuron activity level, while the second task consisted of reaching and maintaining a narrow neuron activity level (i.e. windowed activity task). Main findings . Single neurons in layer V of the motor cortex of rats improved performance during both the thresholded activity and windowed activity BMI tasks. However, correct performance during the windowed activity task was accompanied by activation of neighboring neurons, not in direct control of the BMI. In contrast, only neurons in direct control of the BMI were active at the time of reward during the thresholded activity task. Significance . These results suggest that thresholded activity single-neuron BMI implementations are more appropriate compared to windowed activity BMI tasks to capitalize on the adaptability of cortical circuits to acquire novel arbitrary skills., (© 2021 IOP Publishing Ltd.)

A talent identification index system for male and female cross-country skiers in four age groups (11-12 years old, 13-14 years old, 15-16 years old, and 17-18 years old) was established. The system comprises five body shape indexes ( i =5): Leg-to-Body Ratio (LBR), body fat percentage, maturity status, spreaded brachia index, and upper extremity length. The physiological function indexes ( i =2) are VO 2max and haemoglobin mass (Hb). The psychological indexes ( i =5) cover reaction time, perception speed, a quality-of-will scale, an attention test, and operational thinking. The physical fitness indexes ( i =11) comprise upper limb explosiveness, vertical jump, 3000-metre run, orthostatic forward flexion, closed-eyes single-leg stand, standing long jump, 20-metre sprint, pull-ups (males), flexed arm hang (females), hexagon jump, and a Functional Movement Screen (FMS) test. The athletic performance indexes ( i =3) comprise on-snow time trials for 1.2 km, 5 km, and 10 km. The talent identification evaluation model was created using automated evaluation software. The talent identification index system and evaluation standard table for cross-country skiers passed the P 60 shortlist and P 90 elite boundaries established using the percentile method. Thus, the results of this test profile verify that the evaluative model is objectively effective.

Negative symptoms are characteristic of schizophrenia and closely linked to numerous outcomes. A body of work has sought to identify homogenous negative symptom subgroups-a strategy that can promote mechanistic understanding and precision medicine. However, our knowledge of negative symptom subgroups among individuals at clinical high-risk (CHR) for psychosis is limited. Here, we investigated distinct negative symptom profiles in a large CHR sample (N = 244) using a cluster analysis approach. Subgroups were compared on external validators that are (1) commonly observed in the schizophrenia literature and/or (2) may be particularly relevant for CHR individuals, informing early prevention and prediction. We observed 4 distinct negative symptom subgroups, including individuals with (1) lower symptom severity, (2) deficits in emotion, (3) impairments in volition, and (4) global elevations. Analyses of external validators suggested a pattern in which individuals with global impairments and volitional deficits exhibited more clinical pathology. Furthermore, the Volition group endorsed more disorganized, anxious, and depressive symptoms and impairments in functioning compared to the Emotion group. These data suggest there are unique negative symptom profiles in CHR individuals, converging with studies in schizophrenia indicating motivational deficits may be central to this symptom dimension. Furthermore, observed differences in CHR relevant external validators may help to inform early identification and treatment efforts., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Recent trends in the labor market-marked by instability and insecurity-have further ignited a discourse on the significance of decent work in people's lives. Scholars have mostly studied the multidimensional decent work construct using the composite scores of the Decent Work Scale (DWS; Duffy et al., 2017). However, there may be different combinations of decent work beyond the simple continuum of composite scores. Thus, we employed latent profile analysis to identify profiles of decent work using the 5 subscales of the DWS as indicators. As a result, 5 different groups with distinct profiles emerged: (a) average, (b) low health care, (c) indecent work, (d) only health care, and (e) decent work. Subsequent analyses comparing each group on demographics (gender, employment, education), theoretical predictors (economic constraints, marginalization, work volition), and theoretical outcomes (job satisfaction, life satisfaction) revealed notable differences across the 5 groups. Implications, limitations, and future directions of the results are discussed. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Objective: Negative symptoms and functional outcome have traditionally been assessed using clinical rating scales, which rely on retrospective self-reports and have several inherent limitations that impact validity. These issues may be addressed with more objective digital phenotyping measures. In the current study, we evaluated the psychometric properties of a novel "passive" digital phenotyping method: geolocation., Method: Participants included outpatients with schizophrenia or schizoaffective disorder (SZ: n = 44), outpatients with bipolar disorder (BD: n =19), and demographically matched healthy controls (CN: n = 42) who completed 6 days of "active" digital phenotyping assessments (eg, surveys) while geolocation was recorded., Results: Results indicated that SZ patients show less activity than CN and BD, particularly, in their travel from home. Geolocation variables demonstrated convergent validity by small to medium correlations with negative symptoms and functional outcome measured via clinical rating scales, as well as active digital phenotyping behavioral indices of avolition, asociality, and anhedonia. Discriminant validity was supported by low correlations with positive symptoms, depression, and anxiety. Reliability was supported by good internal consistency and moderate stability across days., Conclusions: These findings provide preliminary support for the reliability and validity of geolocation as an objective measure of negative symptoms and functional outcome. Geolocation offers enhanced precision and the ability to take a "big data" approach that facilitates sophisticated computational models. Near-continuous recordings and large numbers of samples may make geolocation a novel outcome measure for clinical trials due to enhanced power to detect treatment effects., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Operant conditioning is implemented in brain-machine interfaces (BMI) to induce rapid volitional modulation of single neuron activity to control arbitrary mappings with an external actuator. However, intrinsic factors of the volitional controller (i.e. the brain) or the output stage (i.e. individual neurons) might hinder performance of BMIs with more complex mappings between hundreds of neurons and actuators with multiple degrees of freedom. Improved performance might be achieved by studying these intrinsic factors in the context of BMI control. In this study, we investigated how neuron subtypes respond and adapt to a given BMI task. We conditioned single cortical neurons in a BMI task. Recorded neurons were classified into bursting and non-bursting subtypes based on their spike-train autocorrelation. Both neuron subtypes had similar improvement in performance and change in average firing rate. However, in bursting neurons, the activity leading up to a reward increased progressively throughout conditioning, while the response of non-bursting neurons did not change during conditioning. These results highlight the need to characterize neuron-subtype-specific responses in a variety of tasks, which might ultimately inform the design and implementation of BMIs.

Objective: The current study sought to determine whether there is a Bereitschaftspotential (BP) before uninstructed, spontaneous movements., Methods: 14 participants were seated on a comfortable armchair for one hour without any instruction except not to fall asleep and to keep their eyes open. Electroencephalography (EEG) and electromyography (EMG) activity were recorded during the whole session. EEG activity was analyzed before spontaneous movements and compared with EEG activity before repetitive, instructed movements in a separate session., Results: BPs were identified in most participants with the spontaneous movements. The BPs with spontaneous movements were mostly localized in the medial frontocentral regions. The BPs with the instructed movements were localized primarily in the central regions and had larger amplitude., Conclusion: Presence of a BP before movement does not depend on instruction and may be independent of conscious volition. The amplitude of the BP may depend on the amount of attention., Significance: This study shows that the presence of a BP before movement is not an "artifact" of the experimental instructions., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier B.V.)

Volitional control is at the core of brain-machine interfaces (BMI) adaptation and neuroprosthetic-driven learning to restore motor function for disabled patients, but neuroplasticity changes and neuromodulation underlying volitional control of neuroprosthetic learning are largely unexplored. To better study volitional control at annotated neural population, we have developed an operant neuroprosthetic task with closed-loop feedback system by volitional conditioning of population calcium signal in the M1 cortex using fiber photometry recording. Importantly, volitional conditioning of the population calcium signal in M1 neurons did not improve within-session adaptation, but specifically enhanced across-session neuroprosthetic skill learning with reduced time-to-target and the time to complete 50 successful trials. With brain-behavior causality of the neuroprosthetic paradigm, we revealed that proficiency of neuroprosthetic learning by volitional conditioning of calcium signal was associated with the stable representational (plasticity) mapping in M1 neurons with the reduced calcium peak. Furthermore, pharmacological blockade of adenosine A 2A receptors facilitated volitional conditioning of neuroprosthetic learning and converted an ineffective volitional conditioning protocol to be the effective for neuroprosthetic learning. These findings may help to harness neuroplasticity for better volitional control of neuroprosthetic training and suggest a novel pharmacological strategy to improve neuroprosthetic learning in BMI adaptation by targeting striatal A 2A receptors., (Copyright © 2020. Published by Elsevier Ltd.)

How does the brain control an effector as complex and versatile as the hand? One possibility is that neural control is simplified by limiting the space of hand movements. Indeed, hand kinematics can be largely described within 8 to 10 dimensions. This oft replicated finding has been construed as evidence that hand postures are confined to this subspace. A prediction from this hypothesis is that dimensions outside of this subspace reflect noise. To address this question, we track the hand of human participants as they perform two tasks-grasping and signing in American Sign Language. We apply multiple dimension reduction techniques and replicate the finding that most postural variance falls within a reduced subspace. However, we show that dimensions outside of this subspace are highly structured and task dependent, suggesting they too are under volitional control. We propose that hand control occupies a higher dimensional space than previously considered.

A recent conceptual development in schizophrenia is to view its manifestations as interactive networks rather than individual symptoms. Negative symptoms, which are associated with poor functional outcome and reduced rates of recovery, represent a critical need in schizophrenia therapeutics. MIN101 (roluperidone), a compound in development, demonstrated efficacy in the treatment of negative symptoms in schizophrenia. However, it is unclear how the drug achieved its effect from a network perspective. The current study evaluated the efficacy of roluperidone from a network perspective. In this randomized clinical trial, participants with schizophrenia and moderate to severe negative symptoms were randomly assigned to roluperidone 32 mg (n = 78), 64 mg (n = 83), or placebo (N = 83). Macroscopic network properties were evaluated to determine whether roluperidone altered the overall density of the interconnections among symptoms. Microscopic properties were evaluated to examine which individual symptoms were most influential (ie, interconnected) on other symptoms in the network and are responsible for successful treatment effects. Participants receiving roluperidone did not differ from those randomized to placebo on macroscopic properties. However, microscopic properties (degree and closeness centrality) indicated that avolition was highly central in patients receiving placebo and that roluperidone reduced this level of centrality. These findings suggest that decoupling the influence of motivational processes from other negative symptom domains is essential for producing global improvements. The search for pathophysiological mechanisms and targeted treatment development should be focused on avolition, with the expectation of improvement in the entire constellation of negative symptoms if avolition is effectively treated., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Transient shifts in testosterone occur during competition and are thought to positively influence dominance behavior aimed at enhancing social status. However, individual differences in testosterone reactivity to status contests have not been well-studied in relation to real-time expressions of competitive behavior among men and women. This research tests the association between changes in endogenous testosterone levels during competition and performance in terms of competitive endurance. Participant sex, social presence, and relative status outcomes (e.g., winning vs. losing) are tested as moderators of this relationship. In two studies, men and women (total N = 398) competed in the competitive will task (timed weight-holding) either individually or in the presence of an opponent (Study 1) or as a team with and without the presence of a competitor team (Study 2). Results showed a positive relationship between testosterone reactivity and performance for men, particularly those who won or ranked highest among their group - with increasing testosterone predicting better performance and decreasing testosterone predicting worse performance. For women, the effect only emerged among individuals who competed in dyads and lost. In Study 2, an exploratory mediation analysis revealed that individual differences in trait dominance predicted both testosterone reactivity to competition and task performance, with testosterone reactivity (moderated by sex and status outcome) partially explaining the direct relationship between dominance-related traits and behavior. Our goal was to examine testosterone reactivity in relation to real-time competitive effort and highlight the potential role of this relationship in explaining how individual differences in trait dominance produce competitive behavior., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Insight into motivational processes may be gained by examining measures of willingness to exert effort for rewards, which have been linked to neuropsychiatric symptoms of anhedonia and apathy. However, while much work has focused on the development of models of motivation based on classic tasks of externally-generated levels of effort for reward, there has been less focus on the question of self-generated motivation or volition. We developed a task that aims to capture separate measures of self-generated and externally-generated motivation, with two task variants for physical and cognitive effort, and sought to test and validate this measure in two populations of healthy volunteers (N = 27 and N = 28). Similar to previous reports, a sigmoid function represented a better overall fit to the effort-reward data than a linear or Weibull model. Individual sigmoid function shapes were governed by two free parameters: bias (the amount of reward needed for effort initiation) and reward insensitivity (the amount of increase in reward needed to accelerate effort expenditure). For both physical and cognitive effort, bias was higher in the self-generated condition, indicating reduced self-generated volitional effort initiation, compared to externally-generated effort initiation, across effort domains. Bias against initial effort initiation in the self-generated condition was related to a specific dimensional measure of anticipatory anhedonia. For physical effort only, reward insensitivity was also higher in the self-generated condition compared to the externally-generated motivation condition, indicating lower self-generated effort acceleration. This work provides a novel objective measure of self-generated motivation that may provide insights into mechanisms of anhedonia and related symptoms., Competing Interests: In the past 5 years, Dr. Murrough has provided consultation services and/or served on advisory boards for Allergan, Boehreinger Ingelheim, Clexio Biosciences, Fortress Biotech, FSV7, Global Medical Education (GME), Impel Neuropharma, Janssen Research and Development, Medavante-Prophase, Novartis, Otsuka, and Sage Therapeutics. In the past 12 months, Dr. Murrough has provided consultation services and/or served on advisory boards for Boehreinger Ingelheim, Clexio Biosciences, Global Medical Education (GME), and Otsuka. Dr. Murrough is named on a patent pending for neuropeptide Y as a treatment for mood and anxiety disorders and on a patent pending for the use of ezogabine and other KCNQ channel openers to treat depression and related conditions. The Icahn School of Medicine (employer of Dr. Murrough) is named on a patent and has entered into a licensing agreement and will receive payments related to the use of ketamine or esketamine for the treatment of depression. The Icahn School of Medicine is also named on a patent related to the use of ketamine for the treatment of PTSD. Dr. Murrough is not named on these patents and will not receive any payments. This does not alter our adherence to PLOS ONE policies on sharing data and materials. The remaining authors declare no conflicts.

Background: Sexualized drug use (SDU) refers to use of any psychoactive substance before/during sexual intercourse. Chemsex is a subset of SDU, which is defined as the use of some specific psychoactive substances (methamphetamine, mephedrone, γ-hydroxybutyrate, ketamine and cocaine) before/during sexual intercourse. SDU and chemsex are prevalent among gay, bisexual and other men who have sex with men (GBMSM). This study investigated uptake and willingness to use pre-exposure prophylaxis (PrEP) among a sample of GBMSM in Hong Kong with experience of SDU in the past year., Methods: A total of 600 GBMSM were recruited by convenient sampling through outreaching in gay venues, online recruitment and peer referral. Participants completed a cross-sectional anonymous telephone interview. This study was based on a subsample of 580 GBMSM self-reported as HIV negative/unknown sero-status., Results: Of the participants, 82 (14.1%) and 37 (6.4%) had experience of SDU and chemsex in the past year. The prevalence of PrEP uptake was 4.0% among all participants and 14.6% among those with experience of SDU in the past year. Among GBMSM with experience of SDU in the past year who were not on PrEP (n = 70), 67.1% were willing to use daily oral PrEP in the next 6 months. Multivariate logistic regression models showed that positive attitudes toward PrEP (AOR: 2.37, 95%CI: 1.47, 3.82), perceived support from significant others to use PrEP (AOR: 9.67, 95%CI: 2.95, 31.71), and perceived behavioral control of using PrEP (AOR: 19.68, 95%CI: 5.44, 71.26) were significantly associated with higher willingness to use PrEP., Conclusion: GBMSM with experience of recent SDU are potentially good candidates of PrEP implementation. This group of GBMSM reported high prevalence of uptake and willingness to use PrEP. Perceptions related to PrEP based on the Theory of Planned Behavior were significantly associated with willingness to use PrEP.

The relationship between sense of agency and sense of ownership remains unclear. Here we investigated this relationship by manipulating ownership using the rubber hand illusion and assessing the resulting impact on self-experiences during the vicarious agency illusion. We tested whether modulating ownership towards another limb using the rubber hand illusion would subsequently influence the illusory experience of ownership and agency towards a similar-looking limb in the vicarious agency task. Crucially, the vicarious agency task measures both sense of agency and sense of ownership at the same time, while removing the confounding influence of motor signals. Our results replicated the well-established effects of both paradigms. We also found that manipulating the sense of ownership with the rubber hand illusion influenced the subsequent vicarious experience of ownership but not the vicarious experience of agency. This supports the idea that sense of agency and sense of ownership are, at least partially, independent experiences., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The ability to switch efficiently between different tasks underpins cognitive flexibility and is impaired in various psychiatric disorders. Recent research has suggested that the control processes mediating switching can be subject to learning, because "switch readiness" can become associated with, and primed by, specific stimuli. In cued task switching, items that are frequently associated with the need to switch incur a smaller behavioral switch cost than do items associated with a low probability of switching, known as the item-specific switch probability (ISSP) effect (Chiu & Egner, 2017). However, it remains unknown whether ISSP associations modulate the efficiency of only cued switching or also impact people's voluntary choice to switch tasks. Here, we addressed this question by combining an ISSP manipulation with a protocol that mixed 75% standard cued task trials with 25% free choice trials, allowing us to measure the effect of ISSP on voluntary switch rate (VSR). We observed robust ISSP effects on cued trials, replicating previous findings. Crucially, we also found that the VSR was greater for items associated with a high than with a low switch likelihood. We thus demonstrate that associating specific stimuli with frequent switch requirements not only reduces switch costs but also enhances participants' tendency to switch voluntarily. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Magicians have developed powerful tools to covertly force a spectator to choose a specific card. We investigate the physical location force, in which four cards (from left to right: 1-2-3-4) are placed face-down on the table in a line, after which participants are asked to push out one card. The force is thought to rely on a behavioural bias in that people are more likely to choose the third card from their left. Participants felt that their choice was extremely free, yet 60% selected the 3rd card. There was no significant difference in estimates and feelings of freedom between those who chose the target card (i.e. 3rd card) and those who selected a different card, and they underestimated the actual proportion of people who selected the target card. These results illustrate that participants' behaviour was heavily biased towards choosing the third card, but were oblivious to this bias., (Copyright © 2020. Published by Elsevier Inc.)

The current study examined predictors of career choice and life satisfaction among a diverse sample of first-generation college students (N = 424). Grounded in the critical cultural wealth model (CCWM; Garriott, 2019), financial stress, sense of belonging, and work volition were found to directly predict life satisfaction and work volition was found to directly predict career choice satisfaction. Additionally, work volition and/or a sense of belonging were found to significantly mediate the relation of financial stress and experiences of discrimination to career choice and life satisfaction. Invariance testing revealed that the model fit equally well for students identifying as a racial/ethnic minority compared with White students, for freshman/sophomores compared with juniors/seniors, and for students who were part of a first-generation scholarship program versus those who were not. Overall, findings suggest that first-generation students' sense of career choice and life satisfaction is predicted primarily by feelings of work volition and belonging on campus, each of which may be negatively affected by experiencing higher levels of financial stress or discrimination on campus. Implications for research and practice are discussed. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Introduction: There is no standard procedure to evaluated the peak of reflex cough flow (PCF-reflex) in the literature, which is important assessment in subjects with acquired brain injury and tracheostomy cannula. The present study aims to investigate the PCF of the reflex cough in a broad sample of healthy controls and, furthermore, the presence and the strength of voluntary and reflex cough in subjects with ABI with tracheostomy cannula., Materials and Methods: We recruited 147 participants including the healthy subjects (n = 105) and acquired brain injury subjects (n = 43), who underwent respiratory assessment: the Tidal Volume, Forced Vital Capacity, PCF of voluntary cough (PCF-voluntary) and PCF-reflex (using a spirometer connected with a nebulizer by a bidirectional)., Results: The PCF-reflex of controls and subjects was significant lower than the PCF-voluntary (P < 0.01). The PCF-voluntary was not assessed in 26 (60.5 %) subjects due to severe cognitive deficit. In subjects without cognitive deficits (n = 17; 39.5 %), it was significantly lower than in healthy controls (p < 0.01). In contrast, the PCF-reflex was completed in all subjects and it was not significantly different from healthy controls. Furthermore, the strength of the PCF-reflex decreased with increasing inhalation numbers of nebulised air., Conclusion: Reflex cough behaviour differs largely from voluntary cough and the PCF results reflect this great discrepancy. PCF-reflex could be useful parameter for assessing the airway protection whereas PCF-voluntary for measuring airway clearance., (Copyright © 2019 Elsevier B.V. All rights reserved.)

How the involuntary (bulbospinal) and voluntary (corticospinal) pathways interact in respiratory muscle control is not established. To determine the role of excitatory corticobulbar pathways in humans, studies typically compare electromyographic activity (EMG) or evoked responses in respiratory muscles during hypercapnic and voluntary tasks. Although ventilation is matched between tasks by having participants track signals of ventilation, these tasks may not result in matched respiratory muscle activity. The aim of this study was to describe respiratory muscle activity and ribcage and abdominal excursions during two different voluntary conditions, compared to hypercapnic hyperventilation. Ventilation was matched in the voluntary conditions via (i) a simple target of lung volume ('volume tracking') or (ii) targets of both ribcage and abdominal excursions, adjusted to end-expiratory lung volume in hypercapnic hyperventilation ('bands tracking'). Compared to hypercapnic hyperventilation, respiratory parameters such as tidal volume were similar, but the ratio of ribcage to abdominal excursion was higher for both voluntary tasks. Inspiratory scalene and parasternal intercostal muscle activity was higher in volume tracking, but diaphragm and abdominal muscle activity showed little to no change. There were no differences in muscle activity in bands tracking for any muscle, compared to hypercapnic hyperventilation. An elevated ratio of ribcage to abdominal excursion in the bands tracking task indicates that participants could not accurately match the targets in this condition. Inspiratory muscle activity is altered in some muscles in some voluntary tasks, compared to hypercapnia. Therefore, differences in muscle activity should be considered in interpretation of studies that use these protocols to investigate respiratory muscle control., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Objective: The study's purpose was to use validated questionnaires to identify novel behavioral and psychological strategies among weight loss maintainers (WLMs) in a commercial weight management program., Methods: Participants were 4,786 WLMs in WW (formerly Weight Watchers, New York, New York) who had maintained weight loss  ≥ 9.1 kg (24.7 kg/23.8% weight loss on average) for 3.3 years and had a current mean BMI of 27.6 kg/m 2 . A control group of 528 weight-stable individuals with obesity had a mean BMI of 38.9 kg/m 2 and weight change  < 2.3 kg over the previous 5 years., Results: WLMs versus Controls practiced more frequent healthy dietary choices (3.3 vs. 1.9; η p 2  = 0.37), self-monitoring (2.6 vs. 0.7; η p 2  = 0.30), and psychological coping (2.5 vs. 1.1; η p 2  = 0.25) strategies. WLMs also reported more willingness to ignore food cravings (4.4 vs. 3.5; η p 2  = 0.16) and had greater habit strength for healthy eating (5.3 vs. 3.2;  η p 2  = 0.21). Standard canonical coefficients indicated that dietary (0.52), self-monitoring (0.40), and psychological (0.14) strategies as well as habit strength for healthy eating (0.15) contributed independently and most (49.5% of variance) to discriminating groups., Conclusions: In a widely available weight management program, more frequent practice of healthy dietary, self-monitoring, and psychological coping strategies as well as development of greater habit strength for healthy eating differentiated long-term WLMs from weight-stable individuals with obesity., (© 2020 California Polytechnic State University. Obesity published by Wiley Periodicals, Inc. on behalf of The Obesity Society (TOS).)

Hybrid kinetic and kinematic intracortical brain-computer interfaces (iBCIs) have the potential to restore functional grasping and object interaction capabilities in individuals with tetraplegia. This requires an understanding of how kinetic information is represented in neural activity, and how this representation is affected by non-motor parameters such as volitional state (VoS), namely, whether one observes, imagines, or attempts an action. To this end, this work investigates how motor cortical neural activity changes when three human participants with tetraplegia observe, imagine, and attempt to produce three discrete hand grasping forces with the dominant hand. We show that force representation follows the same VoS-related trends as previously shown for directional arm movements; namely, that attempted force production recruits more neural activity compared to observed or imagined force production. Additionally, VoS-modulated neural activity to a greater extent than grasping force. Neural representation of forces was lower than expected, possibly due to compromised somatosensory pathways in individuals with tetraplegia, which have been shown to influence motor cortical activity. Nevertheless, attempted forces (but not always observed or imagined forces) could be decoded significantly above chance, thereby potentially providing relevant information towards the development of a hybrid kinetic and kinematic iBCI.

Vocalization is an ancient vertebrate trait essential to many forms of communication, ranging from courtship calls to free verse. Vocalizations may be entirely innate and evoked by sexual cues or emotional state, as with many types of calls made in primates, rodents and birds; volitional, as with innate calls that, following extensive training, can be evoked by arbitrary sensory cues in non-human primates and corvid songbirds; or learned, acoustically flexible and complex, as with human speech and the courtship songs of oscine songbirds. This review compares and contrasts the neural mechanisms underlying innate, volitional and learned vocalizations, with an emphasis on functional studies in primates, rodents and songbirds. This comparison reveals both highly conserved and convergent mechanisms of vocal production in these different groups, despite their often vast phylogenetic separation. This similarity of central mechanisms for different forms of vocal production presents experimentalists with useful avenues for gaining detailed mechanistic insight into how vocalizations are employed for social and sexual signalling, and how they can be modified through experience to yield new vocal repertoires customized to the individual's social group. This article is part of the theme issue 'What can animal communication teach us about human language?'

Studies of metacognition often measure confidence in perceptual decisions. Much less is known about metacognition of action, and specifically about how people estimate the success of their own actions. In the present study, we compare metacognitive abilities between voluntary actions, passive movements matched to those actions, and purely visual signals. Participants reported their confidence in judging whether a brief visual probe appeared ahead or behind of their finger during simple flexion/extension movement. The finger could be moved voluntarily, or could be moved passively by a robot replaying their own previous movements. In a third condition, participants did not move, but a visual cursor replayed their previous voluntary movements. Metacognitive sensitivity was comparable when judging active movements, during passive finger displacement and visual cursor reply. However, a progressive metacognitive bias was found, with active movements leading to overconfidence in first-level judgement relative to passive movements, at equal levels of actual evidence. Further, both active and passive movements produced overconfidence relative to visual signals. Taken together, our results may partly explain some of the peculiarities that arise when one judges one's own actions., (Copyright © 2019 Elsevier B.V. All rights reserved.)

In the "Libet experiment" the onset of movement-related brain activity preceded the reported time of the conscious intention to move, suggesting that conscious intention may not play a role in initiating voluntary movements (Libet, Gleason, Wright, & Pearl, 1983). Dominik et al. (2017) provided evidence that the intention reports employed in the Libet experiment, which Libet et al. (1983) found to precede movement reports, are invalid. In the study by Dominik et al., intention reports preceded movement reports only when participants had prior experience making movement reports. Individuals without such experience reported intention around the same time as movement. These findings suggest that Libet's intention reports do not reflect experiences of intention, but, rather, inferences based on prior experience with movement reports. Our study replicated the core findings of Dominik et al. We argue that Libet's intention reports are invalid and explore the phenomenology of intention in the Libet experiment., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Methods to reduce intrusive memories (e.g., of traumatic events) should ideally spare voluntary memory for the same event (e.g., to report on the event in court). Single-trace memory accounts assume that interfering with a trace should impact both its involuntary and voluntary expressions, whereas separate-trace accounts assume these two can dissociate, allowing for selective interference. This possibility was investigated in 3 experiments. Nonclinical participants viewed a trauma film followed by an interference task (Tetris game-play after reminder cues). Next, memory for the film was assessed with various measures. The interference task reduced the number of intrusive memories (diary-based, Experiments 1 and 2), but spared performance on well-matched measures of voluntary retrieval-free recall (Experiment 1) and recognition (Experiments 1 and 2)-challenging single-trace accounts. The interference task did not affect other measures of involuntary retrieval-perceptual priming (Experiment 1) or attentional bias (Experiment 2). However, the interference task did reduce the number of intrusive memories in a laboratory-based vigilance-intrusion task (Experiments 2 and 3), irrespective of concurrent working memory load during intrusion retrieval (Experiment 3). Collectively, results reveal a robust dissociation between intrusive and voluntary memories, having ruled out key methodological differences between how these two memory expressions are assessed, namely cue overlap (Experiment 1), attentional capture (Experiment 2), and retrieval load (Experiment 3). We argue that the inability of these retrieval factors to explain the selective interference is more compatible with separate-trace than single-trace accounts. Further theoretical developments are needed to account for this clinically important distinction between intrusive memories and their voluntary counterpart. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

An experience of intention to move accompanies execution of some voluntary actions. The Readiness Potential (RP) is an increasing negativity over motor brain areas prior to voluntary movement. Classical studies suggested that the RP starts before intention is consciously accessed as measured by offline recall-based reports, yet the interpretation of the RP and its temporal relation to awareness of intention remain controversial. We designed a task in which self-paced actions could be interrupted at random times by a visual cue that probed online awareness of intention. Participants were instructed to respond by pressing a key if they felt they were actively preparing a self-paced movement at the time of the cue (awareness report), but to ignore the cue otherwise. We show that an RP-like activity was more strongly present before the cue for probes eliciting awareness reports than otherwise. We further show that recall-based reports of the time of conscious intention are linked to visual attention processes, whereas online reports elicited by a probe are not. Our results suggest that awareness of intention is accessible at relatively early stages of motor preparation and that the RP is specifically associated with this conscious experience., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Psychology of Working Theory (PWT; Duffy, Blustein, Diemer, & Autin, 2016) is a recently developed framework aimed at documenting predictors and outcomes of decent work. To date, no studies have explored the applicability of the psychology of working perspective with emerging adults. The goal of the present study is to examine the predictor portion of PWT with a sample of Korean emerging adults from diverse economic backgrounds. Data were collected from a sample of 407 emerging adults attending a large junior college in Korea. Overall, most of the hypothesized direct paths were significant, with economic resources positively relating to both work volition and career adaptability and these positively relating to occupational engagement and future perceptions of securing decent work. Support for the hypothesized indirect effects was mixed. Overall, results suggest that the PWT is generally relevant and applicable to emerging adults when population-appropriate outcomes are included in the model and that the theory is supported in the Korean context. Based on the results, we also propose that interventions based on malleable psychological factors-the mediators in our study-may be targets when working with emerging adults experiencing economic constraints. (PsycINFO Database Record (c) 2019 APA, all rights reserved).