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The primary goal of this study was to develop a parametric model that relates variation in stimulation of the trigeminal nerve to properties of the blink response. We measured blink responses in 17 healthy, adult participants to air puffs directed at the lateral canthus of the eye at five different, log‐spaced intensities (3.5–60 PSI). Lid position over time was decomposed into amplitude and velocity components. We found that blink amplitude was systematically related to log stimulus intensity, with the relationship well described by a sigmoidal function. The parameters of the model fit correspond to the slope of the function and the stimulus intensity required to produce half of a maximal blink response (the half‐response threshold). There was a reliable increase in the half‐response threshold for the contralateral as compared to the ipsilateral blink response. This increase was consistent across participants despite substantial individual differences in the half‐response threshold and slope parameters of the overall sensitivity function, suggesting that the laterality effect arises in the neural circuit subsequent to individual differences in sensitivity. Overall, we find that graded mechanical stimulation of the somatosensory trigeminal afferents elicits a graded response that is well described by a simple parametric model. We discuss the application of parametric measurements of the blink response to the detection of group differences in trigeminal sensitivity. There has been limited study of how variation in stimulus intensity influences the cutaneous blink response. We describe how variation in the intensity of an air puff stimulus relates to the amplitude of the blink response using a two‐parameter model. The parameters of the model capture individual differences in response, which may be used in future studies to identify population differences in trigeminal sensitivity. [ABSTRACT FROM AUTHOR]

The generalization of music training to unrelated nonmusical domains is well established and may reflect musicians' superior ability to regulate attention. We investigated the temporal deployment of attention in musicians and nonmusicians using scalp‐recording of event‐related potentials in an attentional blink (AB) paradigm. Participants listened to rapid sequences of stimuli and identified target and probe sounds. The AB was defined as a probe identification deficit when the probe closely follows the target. The sequence of stimuli was preceded by a neutral or informative cue about the probe position within the sequence. Musicians outperformed nonmusicians in identifying the target and probe. In both groups, cueing improved target and probe identification and reduced the AB. The informative cue elicited a sustained potential, which was more prominent in musicians than nonmusicians over left temporal areas and yielded a larger N1 amplitude elicited by the target. The N1 was larger in musicians than nonmusicians, and its amplitude over the left frontocentral cortex of musicians correlated with accuracy. Together, these results reveal musicians' superior ability to regulate attention, allowing them to prepare for incoming stimuli, thereby improving sound object identification. This capacity to manage attentional resources to optimize task performance may generalize to nonmusical activities. [ABSTRACT FROM AUTHOR]

Attending to a single feature, such as color or motion, leads to global modulation of neural processing associated with the representation of the attended features. Alpha‐band modulations are hypothesized to be a marker (and even a mechanism) of the modulation of neural processing. By adopting a previously used attentional shifting paradigm, we examined whether alpha‐band dynamics are linked to sustained Feature‐Based‐Attentional (FBA) selection. For this purpose, we presented task‐irrelevant flickering random dot kinematograms (RDKs) in the periphery that either did or did not share the to‐be‐attended color of centrally presented task‐relevant RDKs and should thus be subject to global FBA selection. Steady‐state visual evoked potentials (SSVEPs) and alpha‐band activity associated with these task‐irrelevant RDKs were analyzed to quantify FBA modulation. Overall, the SSVEP results replicated previous findings: relative to a pre‐cue baseline, SSVEP amplitudes for peripheral RDKs were significantly enhanced when these RDKs shared the to‐be‐attended color of the central RDKs and were not modulated when they shared the centrally to‐be‐ignored color. Nevertheless, there were no differences in alpha‐band amplitude modulations between signals recorded contralateral to the RDKs sharing the centrally attended color and RDKs sharing the centrally ignored color. Hence, alpha‐band modulations seem not to index the sustained global selection of attended over unattended feature values within the same feature dimension. This study assesses the role of alpha‐band dynamics as a potential candidate to implement attentional selection in feature‐based attention, e.g., when looking for a specific color. The results demonstrate the known effect of global enhancement of the to‐be‐attended color outside the focus of spatial attention as measured by modulation of steady‐state visual evoked potentials but not alpha‐band dynamics. Thus, alpha‐band modulations are not associated with the sustained and global selection of attended over unattended feature values of the same feature dimension in visual feature‐based attention. [ABSTRACT FROM AUTHOR]

The conflict monitoring theory postulates that conflict detection is initiated in the anterior cingulate cortex (ACC), indexed by midfrontal theta oscillations in the electroencephalogram (EEG). Recent research suggested that distractor detection (in the Eriksen flanker task) can be initiated relatively early by attentional control processes in the occipital lobe. Whether attentional control is also involved in the detection of stimulus–response overlapping conflict in the Stroop task is yet unclear. In the present study, we analyzed EEG time‐frequency data (N = 47) to investigate the contribution of early attentional control processes to the detection of response conflict and semantic conflict in a lateralized version of the color‐word Stroop task. The behavioral results showed significant conflict effects in response times (RT). The EEG results showed a prominent midfrontal response conflict effect in total theta power (4–8 Hz). Importantly, detection of response conflict and semantic conflict was observed in posterior delta/theta power (2–8 Hz), which was lateralized depending on the presentation side of the irrelevant Stroop words. In explorative regression analysis, both the midfrontal and the posterior response conflict effects predicted the size of response conflict errors. These results suggest that attentional control processes in posterior areas contribute to the initiation of response‐conflict detection in the Stroop task. The findings are consistent with the idea of a representational link between stimulus and response features, known as the common coding principle. This study provides evidence for a conflict detection signal in EEG delta/theta power in a lateralized version of the Stroop task. The posterior signal was associated to response conflict and to semantic conflict. This finding challenges the conflict monitoring account, which postulates that conflict detection is initiated in the anterior cingulate cortex (ACC), as reflected by midfrontal theta power increase. [ABSTRACT FROM AUTHOR]

Attentional blink (AB) is the impaired detection of a second target (T2) after a first target has been identified. In this paper, we investigated the functional roles of alpha and theta oscillations on AB by determining how much preceding rhythmic auditory stimulation affected the performance of AB. Healthy young adults participated in the experiment online. We found that when two targets were embedded in rapid serial visual presentation (RSVP) of distractors at 10 Hz (i.e., alpha frequency), the magnitude of AB increased with auditory stimuli. The increase was limited to the case when the frequency and phase of auditory stimuli matched the following RSVP stream. On the contrary, when only two targets were presented without distractors, auditory stimuli at theta, not alpha, increased the AB magnitude. These results indicate that neural oscillations at two different frequencies, namely, alpha and theta, are involved in attentional blink. [ABSTRACT FROM AUTHOR]

Aim: Emerging evidence suggests that transcranial direct current stimulation (tDCS) has anxiolytic effects and may enhance emotional processing of threat and reduce threat‐related attentional bias. Panic disorder (PD) is considered to be a fear network disorder along with prefrontal activity alterations. We aim to assess the effect of tDCS on clinical and physiological parameters in PD for the first time. Methods: In this triple‐blind randomized sham‐controlled pilot study, 30 individuals with PD were allocated into active and sham groups to receive 10 sessions of tDCS targeting the dorsolateral prefrontal cortex bilaterally at 2 mA for 20‐min duration over 2 weeks. The clinical severity, threat‐related attentional bias, interoceptive accuracy, and emotional recognition were assessed before, immediately after, and 1 month after tDCS. Results: Active tDCS, in comparison to sham, did not elicit more favorable clinical and neuropsychological/physiological outcomes in PD. Conclusion: The present study provides the first clinical and neurobehavioral results of prefrontal tDCS in PD and indicates that prefrontal tDCS was not superior to sham in PD. [ABSTRACT FROM AUTHOR]

Previous research established that rhythmic sensory stimulation can affect subsequent stimulus perception, possibly through 'entrainment' of oscillations in the brain. Alpha frequency is a natural target for visual entrainment, because fluctuations in posterior alpha oscillations have been linked to visual target detection or discrimination. On the other hand, alpha oscillations also relate to attentional mechanisms, such as attentional orienting or selection. Previous visual alpha entrainment studies focused on differential processing of targets presented in‐phase with the preceding rhythmic stimulation relative to out‐of‐phase targets (an 'SOA effect'), putatively related to the phase of entrained neuronal alpha oscillations. Fewer studies probed the consequences of rhythmic alpha stimulation for attention mechanisms related to alpha power. Here, we asked whether alpha stimulation of one hemifield has similar effects on reaction times as we see for increased alpha synchronization in magneto/electroencephalography (M/EEG) studies (i.e., more alpha means impaired processing and functional inhibition). We implemented a task inspired by attention studies, assessing reaction times to ipsilateral vs. contralateral visual targets, with and without concurrent presentation of distractors. Yet, in place of any attention cues, we presented a rhythmic, vs. arrhythmic, alpha‐frequency train of visual flashes to one hemifield, in a large sample size (N = 115) in an online experiment. We found clear evidence that flash train rhythmicity did not impact task performance. We also found that the spatial congruence between the unilateral flash train and the subsequent visual target did impact response times but only in the presence of contralateral distractor stimuli. We discuss implications, limitations and future directions. [ABSTRACT FROM AUTHOR]

The visual attentional blink can be substantially reduced by delivering a task‐irrelevant sound synchronously with the second visual target (T2), and this effect is further modulated by the semantic congruency between the sound and T2. However, whether the cross‐modal benefit originates from audiovisual interactions or sound‐induced alertness remains controversial, and whether the semantic congruency effect is contingent on audiovisual temporal synchrony needs further investigation. The current study investigated these questions by recording event‐related potentials (ERPs) in a visual attentional blink task wherein a sound could either synchronize with T2, precede T2 by 200 ms, be delayed by 100 ms, or be absent, and could be either semantically congruent or incongruent with T2 when delivered. The behavioral data showed that both the cross‐modal boost of T2 discrimination and the further semantic modulation were the largest when the sound synchronized with T2. In parallel, the ERP data yielded that both the early occipital cross‐modal P195 component (192–228 ms after T2 onset) and late parietal cross‐modal N440 component (424–448 ms) were prominent only when the sound synchronized with T2, with the former being elicited solely when the sound was further semantically congruent whereas the latter occurring only when that sound was incongruent. These findings demonstrate not only that the cross‐modal boost of T2 discrimination during the attentional blink stems from early audiovisual interactions and the semantic congruency effect depends on audiovisual temporal synchrony, but also that the semantic modulation can unfold at the early stage of visual discrimination processing. [ABSTRACT FROM AUTHOR]

The goal of this study was to examine activities and experiences where enhanced cognitive states (ECSs), characterized by dramatic boosts in focused attention, could be elicited under specific gaming contexts. In Experiment 1, expert gamers were tested on the attentional blink task before and after playing games of different genres, varying on four game design dimensions (perspective, "adrenaline‐rush," immersivity, and collaborative vs. individual context) and two cognitive dimensions (speed of processing and attentional focus). In Experiment 2, using ECG‐HRV methodology, we examined the physiological markers of gaming dimensions found to be critical for accessing ECSs in Experiment 1. The findings suggest that ECSs are a universal phenomenon that demands focusing one's attention on a single task from the egocentric perspective, and ought to involve an adventurous "adrenaline‐rush" type of activity. Furthermore, the results demonstrated that an underlying physiological mechanism of ECSs includes parasympathetic nervous system (PSNS) withdrawal‐associated arousal. Specifically, the gaming dimensions leading to greater PSNS withdrawal‐associated arousal resulted in greater improvements on the attentional blink task during ECSs. These findings suggest that individuals can transcend what was hitherto assumed to be a limitation of human cognition, granting new prospects for eliciting exceptional human performance. [ABSTRACT FROM AUTHOR]

The trigeminal primary sensory neurons that innervate the ocular surface, especially the cornea, have been classified in three functional types: polymodal nociceptors, mechano‐nociceptors and cold thermoreceptors. These sensory nerves are responsible for the conscious sensations evoked in response to ocular surface stimulation as well as for the regulation of tearing and blinking, and they are also involved in the trophic maintenance of the ocular tissues. Depending on the transducing channels they express in their membrane, sensory nerves from the ocular surface respond to different types of stimulus and, after this information is processed by the CNS, different conscious sensations are evoked: corneal mechano‐nociceptors' activation led to pricking pain; polymodal nociceptors evoke burning irritation, and cold thermoreceptors' activation may evoke freshness/cold/dryness/pain depending on the subtype of cold thermoreceptor neuron activated by the stimulus. While reflex blinking and tearing are driven by the activation of polymodal nociceptors as the afferent arm of the reflex, basal blinking and tearing rate are under the control of cold thermoreceptors' activity. During inflammation and after injury (such as UV‐induced keratitis, allergic keratoconjunctivitis, corneal surgery, tear‐deficient dry eye) the activity of corneal sensory nerves is modified in both eyes, even when inflammation or damage affects only one eye. The abnormal corneal sensory nerve activity constitutes the basis for the discomfort, dryness and pain sensations experienced under these conditions. Also, protective mechanisms depending on ocular nerve activity such as blinking and tearing become altered. (Supported by PID2020‐115934RB‐I00 from DOI: MCIN/AEI/10.13039/50110001103, and CIPROM/2021/48 from the Generalitat Valenciana, Spain) [ABSTRACT FROM AUTHOR]

The cornea is innervated trigeminal neurons classified in three different functional types: polymodal nociceptor, mechano‐nociceptor and cold thermoreceptor neurons. Corneal sensory nerves are responsible of the conscious sensations evoked by corneal stimulation, and are also involved in the trophic maintenance of the tissue. Besides, corneal nerve activity is also involved in the regulation of the protective functions of the ocular surface such as tearing and blinking. Regulation of reflex and basal tearing is integrated at the brainstem and, in both cases, under the influence of the sensory inflow provided by several types of corneal sensory nerves. While reflex tearing is induced selectively by the stimulation of corneal polymodal nociceptors, basal tearing rate depends on the spontaneous activity of cold thermoreceptors. Thus, when cold thermoreceptors are silenced by environmental warming, basal tearing is compromised. Voluntary, reflex and spontaneous (basal) blinking present differences in their characteristics and regulation mechanisms. Voluntary blinking depends on the direct instructions generated at the brain cortex, acting over the motor neurons located at the facial nucleus. Reflex blinking is integrated at the brainstem, being induced by the stimulation of the cornea and periocular skin, and even by loud sounds. Spontaneous blinking is claimed to be controlled by a CNS centre that established a blinking pattern. This pattern is modified under different conditions such as cognitive activity, being for example reduced during visual attentional tasks in order not to lose relevant visual information. When the activity of corneal cold thermoreceptors is abolished or reduced by ocular instillation of local anaesthetics, the frequency and characteristics of the spontaneous blinking is not modified. However, when the activity of cold thermoreceptors is increased for prolonged periods (for instance after topical instillation of F6H8 drops, which reduces the ocular surface temperature), blinking pattern become more regular and an increased number of blinks of larger the amplitude and shorter duration are induced. This increased blinking frequency produced when the activity of cold thermoreceptors is increased is sufficient to even counteract the reduction of blinking frequency induced during visual tasks performance. The increase in blink frequency driven by corneal cold thermoreceptors' activation may constitute a protective mechanism to prevent excessive desiccation of the ocular surface. (Supported by PID2020‐115934RB‐I00 from DOI: MCIN/AEI/10.13039/50110001103, and CIPROM/2021/48 from the Generalitat Valenciana, Spain) [ABSTRACT FROM AUTHOR]