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Two experiments investigated what eye movements can reveal about how we process surprising information and how we update mental models in dynamic and unstructured environments. Participants made saccades to visual targets presented one at a time, radially, around an invisible perimeter. Target locations were normally distributed and shifted at an unannounced point during the task. Trials following the shift were considered surprising and unexpected. These unexpected and surprising events prompted the need to update. Slower saccadic latencies were observed for surprising/unexpected events, perhaps indicative of the need to reorient attention to the unexpected target location. Longer dwell times were observed for events that signaled a change in the distribution. These data show that eye movement metrics provide a reliable indicator of mental model updating when contingencies change even in the absence of explicit change signals.

We examined the hypothesis that boredom is likely to occur when opportunity costs are high; that is, when there is a high potential value of engaging in activities other than the researcher-assigned activity. To this end, participants were either placed in a room with many possible affordances (e.g. a laptop, puzzle, etc.; affordances condition; n = 121), or they were ushered into an empty room (control condition; n = 107). In both conditions participants were instructed to entertain themselves with only their thoughts (hence, participants in the affordances condition were to refrain from engaging with the available options). As predicted, participants in the affordances condition reported higher levels of boredom compared with those in the control condition. Results suggest that under some conditions, environments that afford alternative activities may be more boring than those that are void of such activities.

For over a century, research has demonstrated that damage to primary visual cortex does not eliminate all capacity for visual processing in the brain. From Riddoch's (1917) early demonstration of intact motion processing for blind field stimuli, to the iconic work of Weiskrantz et al. (1974) showing reliable spatial localization, it is clear that secondary visual pathways that bypass V1 carry information to the visual brain that in turn influences behavior. In this chapter, we briefly outline the history and phenomena associated with blindsight, before discussing the nature of the secondary visual pathways that support residual visual processing in the absence of V1. We finish with some speculation as to the functional characteristics of these secondary pathways.

Boredom, the unfulfilled desire to be engaged in a satisfying mental activity, is an aversive state characterized by poor self-regulation. There is ample evidence that both state and trait boredom are associated with failures of attention in both experimental and everyday settings. The neural correlates of boredom, however, remain underexplored. We recorded electroencephalographic signal from 83 participants during a resting state and while performing a go/no-go task. We found a negative correlation between trait boredom proneness and power in the alpha and theta bands during the resting state. Furthermore, higher levels of task-induced boredom were associated with reduced amplitudes for the P3 and error-related negativity event-related potentials. Increased commission error rates were also associated with higher levels of task-induced boredom. We conclude that state and trait boredom are associated with inadequate engagement of attentional resources.

Children until the age of five are only able to reverse an ambiguous figure when they are informed about the second interpretation. In two experiments, we examined whether children’s difficulties would extend to a continuous version of the ambiguous figures task. Children (Experiment 1: 66 3- to 5-year olds; Experiment 2: 54 4- to 9-year olds) and adult controls saw line drawings of animals gradually morph—through well-known ambiguous figures—into other animals. Results show a relatively late developing ability to recognize the target animal, with difficulties extending beyond preschool-age. This delay can neither be explained with improvements in theory of mind, inhibitory control, nor individual differences in eye movements. Even the best achieving children only started to approach adult level performance at the age of 9, suggesting a fundamentally different processing style in children and adults. Electronic supplementary material The online version of this article (10.1007/s00426-019-01278-z) contains supplementary material, which is available to authorized users.

The state of boredom arises when we have the desire to be engaged in goal pursuit, but for whatever reason we cannot fulfil that desire. Boredom proneness is characterized by both frequent and intense feelings of boredom and is an enduring individual difference trait associated with a raft of negative outcomes. There has been some work in educational settings, but relatively little is known about the consequences of boredom proneness for learning. Here we explored the unique contributions of boredom proneness, self-control and self-esteem to undergraduate self-reported higher grade point average (GPA). Within educational settings, prior research has shown self-control and self-esteem to be associated with better academic performance. In contrast, boredom proneness is associated with lower levels of self-control and self-esteem. Our analyses replicate those previous findings showing that self-control acts as a positive predictor of GPA. Importantly, we further demonstrated, for the first time, that boredom proneness has a unique contribution to GPA over and above the contribution of self-control, such that as boredom proneness increases, GPA decreases. We discuss potential mechanisms through which boredom proneness may influence academic performance.

Previous research shows that individuals who tend to get bored frequently and intensely—the highly boredom prone—are more likely to engage in risky behaviors. However, these studies are based largely on self-reports. Here we address this gap and suggest that noisy decision-making (DM) is a potential driver for this relationship between boredom proneness and risk-taking. In Study 1, eighty-six participants completed the Balloon Analogue Risk Task (BART) while EEG was recorded. We found blunted feedback processing with higher boredom proneness, as indexed by reduced feedback-P3 amplitudes. Risk taking, as indexed by the BART, was not higher in the highly boredom prone. In Study 2a (N = 404) we directly tested the noisy DM hypothesis in an online sample using a binary choice task, and found that with higher boredom proneness, participants were more likely to alternate between choices on a trial-to-trial basis, but were not more likely to choose the risky alternative. These findings were replicated in a new sample (Study 2b), and extended to the Iowa Gambling Task (IGT; Study 3). In the IGT we found increased choice switching and reduced feedback sensitivity with higher boredom proneness. Once again, higher risk taking as indexed by the IGT was not evident in the highly boredom prone. Overall, our findings suggest that boredom proneness is associated with noisy decision-making (i.e., a tendency to alternate more between choice options regardless of risk level), and not risk-seeking per se. That is, the highly boredom prone are not necessarily attracted to risks, but rather, may be insensitive to risks due to reduced feedback sensitivity.

Visual working memory (VWM) involves the encoding and maintenance of visual information over time, with the requirement that object features be accurately bound to spatial locations. We and others have shown that damage to the right hemisphere leads to impaired spatial working memory. Here, we test the notion that right brain damage (RBD) may have consequences for domain general VWM. We had eight RBD patients and a group of healthy control participants perform a VWM task under different loads (1 to 3 items to recall) and spatial competition (high vs. low). All participants were asked to remember the colour of target items presented on the right side of space. Patients showed impaired encoding of information evident in poor precision of memory representations and increased guessing rates even at a set size of only one item. Our data suggests that VWM capacity is severely limited following RBD. Although five of the eight patients presented with neglect, it is not clear whether this deficit in VWM is unique to the syndrome. We suggest that future work should directly pit attention and VWM demands against one another in the same patients to determine whether the confluence of deficits in these domains is the critical determinant of the neglect syndrome. Regardless of the implications for the neglect syndrome, however, our data show that VWM deficits in RBD patients extend into non-spatial feature space.

We have shown recently that damage to the right hemisphere impairs the ability to update mental models when evidence suggests an old model is no longer appropriate. We argue that this deficit is generic in the sense that it crosses multiple cognitive and perceptual domains. Here, we examined the nature of this updating impairment to determine more precisely the underlying mechanisms. We had right (RBD, N = 12) and left brain damaged (LBD, N = 10) patients perform versions of our picture-morphing task in which pictures gradually morph from one object (e.g., shark) to another (e.g., plane). Performance was contrasted against two groups of healthy older controls, one matched on age (HCO-age-matched, N = 9) and another matched on general level of cognitive ability (HCO-cognitively-matched, N = 9). We replicated our earlier findings showing that RBD patients took longer than LBD patients and HCOs to report seeing the second object in a sequence of morphing images. The groups did not differ when exposed to a morphing sequence a second time, or when responding to ambiguous images outside the morphing context. This indicates that RBD patients have little difficulty alternating between known representations or labeling ambiguous images. Instead, the difficulty lies in generating alternate hypotheses for ambiguous information. Lesion overlay analyses, although speculative given the sample size, are consistent with our fMRI work in healthy individuals in implicating the anterior insular cortex as critical for updating mental models.

In a constantly changing environment we must adapt to both abrupt and gradual changes to incoming information. Previously, we demonstrated that a distributed network (including the anterior insula and anterior cingulate cortex) was active when participants updated their initial representations (e.g., it's a cat) in a gradually morphing picture task (e.g., now it's a rabbit; Stöttinger et al., 2015). To shed light on whether these activations reflect the proactive decisions to update or perceptual uncertainty, we introduced two additional conditions. By presenting picture morphs twice we controlled for uncertainty in perceptual decision making. Inducing an abrupt shift in a third condition allowed us to differentiate between a proactive decision in uncertainty-driven updating and a reactive decision in surprise-based updating. We replicated our earlier result, showing the robustness of the effect. In addition, we found activation in the anterior insula (bilaterally) and the mid frontal area/ACC in all three conditions, indicative of the importance of these areas in updating of all kinds. When participants were naïve as to the identity of the second object, we found higher activations in the mid-cingulate cortex and cuneus – areas typically associated with task difficulty, in addition to higher activations in the right TPJ most likely reflecting the shift to a new perspective. Activations associated with the proactive decision to update to a new interpretation were found in a network including the dorsal ACC known to be involved in exploration and the endogenous decision to switch to a new interpretation. These findings suggest a general network commonly engaged in all types of perceptual decision making supported by additional networks associated with perceptual uncertainty or updating provoked by either proactive or reactive decision making.

The current study represents the first comprehensive examination of spatial, temporal and sustained attention following cerebellar damage. Results indicated that, compared to controls, cerebellar damage resulted in a larger cueing effect at the longest SOA – possibly reflecting a slowed the onset of inhibition of return (IOR) during a reflexive covert attention task, and reduced the ability to detect successive targets during an attentional blink task. However, there was little evidence to support the notion that cerebellar damage disrupted voluntary covert attention or the sustained attention to response task (SART). Lesion overlay data and supplementary voxel-based lesion symptom mapping (VLSM) analyses indicated that impaired performance on the reflexive covert attention and attentional blink tasks were related to damage to Crus II of the left posterior cerebellum. In addition, subsequent analyses indicated our results are not due to either general motor impairments or to damage to the deep cerebellar nuclei. Collectively these data demonstrate, for the first time, that the same cerebellar regions may be involved in both spatial and temporal visual attention.

Characterized as an agitated state in which the individual is motivated to engage in their environment but all attempts to do so fail to satisfy, boredom represents a disengaged attentional state that is associated with negative affect and poor self-control. There have been anecdotal reports of increased levels of boredom post-traumatic brain injury (TBI). For the first time, we provide objective evidence that TBI patients do indeed experience higher levels of boredom proneness. Hierarchical regression analyses showed that the presence and severity of head injury were a significant positive predictor of levels of boredom proneness and a negative predictor of self-control. As with healthy controls, TBI patients showed a strong negative correlation between boredom proneness and self-control-those with lower levels of self-control exhibited higher levels of boredom proneness. This was despite the fact that our TBI patients reported higher overall levels of self-control (probably concomitant with their older mean age). The TBI patients also showed strong positive correlations between boredom proneness and measures of physical aggression and anger. Together, this suggests that patients with TBI may be more susceptible to increased levels of boredom proneness and other negative affective states that arise as a consequence of failures of self-control.

In order to survive in a complex, noisy and constantly changing environment we need to categorize the world (e.g., Is this food edible or poisonous?) and we need to update our interpretations when things change. How does our brain update when object categories change from one to the next? We investigated the neural correlates associated with this updating process. We used event-related fMRI while people viewed a sequence of images that morphed from one object (e.g., a plane) to another (e.g., a shark). All participants were naïve as to the identity of the second object. The point at which participants 'saw' the second object was unpredictable and uncontaminated by any dramatic or salient change to the images themselves. The moment when subjective perceptual representations changed activated a circumscribed network including the anterior insula, medial and inferior frontal regions and inferior parietal cortex. In a setting where neither the timing nor nature of the visual transition was predictable, this restricted cortical network signals the time of updating a perceptual representation. The anterior insula and mid-frontal regions (including the ACC) were activated not only at the actual time when change was reported, but also immediately before, suggesting that these areas are also involved in processing alternative options after a mismatch has been detected.

Boredom is a common experience associated with a range of negative outcomes. Debate remains as to whether boredom should be considered a high or low arousal state. We employed passages of text to induce either boredom or interest and probed self-reported levels of boredom, arousal, and restlessness. Results replicated known associations between mind-wandering and state boredom (i.e., mind-wandering was highest for the boredom mood induction). Reports of sleepiness (a proxy for arousal level) were highest for the boring induction. While restlessness was not different for the boring and interesting inductions when they were performed first, restlessness was significantly higher for the boredom induction when it was experienced last. We discuss these results within the context of the debate regarding boredom and arousal.

Effectively engaging with the world depends on accurate representations of the regularities that make up that world-what we call mental models. The success of any mental model depends on the ability to adapt to changes-to 'update' the model. In prior work, we have shown that damage to the right hemisphere of the brain impairs the ability to update mental models across a range of tasks. Given the disparate nature of the tasks we have employed in this prior work (i.e. statistical learning, language acquisition, position priming, perceptual ambiguity, strategic game play), we propose that a cognitive module important for updating mental representations should be generic, in the sense that it is invoked across multiple cognitive and perceptual domains. To date, the majority of our tasks have been visual in nature. Given the ubiquity and import of temporal information in sensory experience, we examined the ability to build and update mental models of time. We had healthy individuals complete a temporal prediction task in which intervals were initially drawn from one temporal range before an unannounced switch to a different range of intervals. Separate groups had the second range of intervals switch to one that contained either longer or shorter intervals than the first range. Both groups showed significant positive correlations between perceptual and prediction accuracy. While each group updated mental models of temporal intervals, those exposed to shorter intervals did so more efficiently. Our results support the notion of generic capacity to update regularities in the environment-in this instance based on temporal information. The task developed here is well suited to investigations in neurological patients and in neuroimaging settings.

The ability to accurately build and update mental representations of our environment depends on our ability to integrate information over a variety of time scales and detect changes in the regularity of events. As such, the cognitive mechanisms that support model building and updating are likely to interact with those involved in working memory (WM). To examine this, we performed three experiments that manipulated WM demands concurrently with the need to attend to regularities in other stimulus properties (i.e., location and shape). That is, participants completed a prediction task while simultaneously performing an n-back WM task with either no load or a moderate load. The distribution of target locations (Experiment 1) or shapes (Experiments 2 and 3) included some level of probabilistic regularity, which, unbeknown to participants, changed abruptly within each block. Moderate WM load hampered the ability to benefit from target regularities and to adapt to changes in those regularities (i.e., the prediction task). This was most pronounced when both prediction and WM requirements shared the same target feature. Our results show that representational updating depends on free WM resources in a domain-specific fashion.

In many research domains, researchers have employed gradually morphing pictures to study perception under ambiguity. Despite their inherent utility, only a limited number of stimulus sets are available, and those sets vary substantially in quality and perceptual complexity. Here we present normative data for 40 morphing picture series. In all sets, line drawings of pictures of common objects are morphed over 15 iterations into a completely different object. Objects are either morphed from an animate to an inanimate object (or vice versa) or morphed within the animate and inanimate object categories. These pictures, together with the normative naming data presented here, will be of value for research on a diverse range of questions, from perceptual processing to decision making.

The current study examined the influence of redundant stimulus features on our ability to build and update representations of our environment. We hypothesized that our ability to process redundant spatial features would speed our ability to adapt to changing nonspatial regularities. Using a computerized version of the children's game “rock–paper–scissors”, undergraduates were instructed to win as often as possible against a computer opponent. The computer's plays were repeating sequences of five choices that were presented either with spatial regularity (i.e., “rock” would always appear on the left, “paper” in the middle, and “scissors” on the right) or without spatial regularity (i.e., the items were equally likely to appear in any of the three locations). Once participants learned a sequence, the computer switched to a different sequence without participants being informed that a switch had occurred. Redundant spatial regularity improved a participant's ability both to learn sequences of plays and to update their plays to reflect new computer sequences. Our results suggest that our perceptual system is sensitive to redundant spatial stimulus features and that this information can improve learning and updating.

To explore how model building adapts to changing environments, we had participants play "rock-paper-scissors" against a computer that played a frequency bias or a player-dependent bias and then switched. Participants demonstrated their use of prior experience in how quickly they recognized and exploited changes in the computer's play strategy; in general, the more similar the strategies, the more efficient the updating. These findings inform our understanding of previously reported updating impairments in right-brain damaged patients.

It has been hypothesized that many of the cognitive impairments commonly seen after right brain damage (RBD) can be characterized as a failure to build or update mental models. We (Danckert et al. in Neglect as a disorder of representational updating. NOVA Open Access, New York, 2012a; Cereb Cortex 22:2745–2760, 2012b) were the first to directly assess the association between RBD and updating and found that RBD patients were unable to exploit a strongly biased play strategy in their opponent in the children’s game rock, paper, scissors. Given that this game required many other cognitive capacities (i.e., working memory, sustained attention, reward processing), RBD patients could have failed this task for various reasons other than a failure to update. To assess the generality of updating deficits after RBD, we had RBD, left brain-damaged (LBD) patients and healthy controls (HCs) describe line drawings that evolved gradually from one figure (e.g., rabbit) to another (e.g., duck) in addition to the RPS updating task. RBD patients took significantly longer to alter their perceptual report from the initial object to the final object than did LBD patients and HCs. Although both patient groups performed poorly on the RPS task, only the RBD patients showed a significant correlation between the two, very different, updating tasks. We suggest these data indicate a general deficiency in the ability to update mental representations following RBD.

Boredom proneness has been linked to various forms of cognitive and affective dysregulation including poor self-control and mind-wandering (MW), as well as depression and aggression. As such, understanding boredom and the associated cognitive and affective components of the experience, represents an important first step in combatting the consequences of boredom for psychological well-being. We surveyed 1928 undergraduate students on measures of boredom proneness, self-control, MW, depression and aggression to investigate how these constructs were related. Hierarchical regression analysis indicated that self-control operated as a strong negative predictor of boredom proneness. Finally, when controlling for age and self-control, we observed large decreases in the magnitudes of the relationships between boredom proneness and our other measures of interest. Together, these results imply a strong relationship between boredom proneness and cognitive and affective dysregulation, and show that individual levels of self-control can account for the lion’s share of variance in the relationships between boredom, cognition, and affect.

We recently proposed that the right hemisphere plays a crucial role in the processes underlying mental model building and updating. Here, we review the evidence we and others have garnered to support this novel account of right hemisphere function. We begin by presenting evidence from patient work that suggests a critical role for the right hemisphere in the ability to learn from the statistics in the environment (model building) and adapt to environmental change (model updating). We then provide a review of neuroimaging research that highlights a network of brain regions involved in mental model updating. Next, we outline specific roles for particular regions within the network such that the anterior insula is purported to maintain the current model of the environment, the medial prefrontal cortex determines when to explore new or alternative models, and the inferior parietal lobule represents salient and surprising information with respect to the current model. We conclude by proposing some future directions that address some of the outstanding questions in the field of mental model building and updating. (PsycINFO Database Record

Research has shown that damage to either the left or right hemisphere can lead to deficits in visuoconstructional skills including drawing and figure copying. Nevertheless, research would suggest that the nature of the deficits arising from left and right brain injury are distinct in nature if not severity, with the right hemisphere, and parietal cortex specifically, seen as critical for obtaining accurate spatial relations and the left hemisphere important for effective organisation (i.e., executive function). Much of this work on drawing and figure copying following brain damage has rested on qualitative assessments or crude marking scales with descriptive anchors for what constitutes good or poor performance. We employed quantitative analyses of drawings developed to assess accuracy in novice and expert artists. We analyzed drawings of a cube and a star in 50 patients (23, left brain damaged: LBD; 27 right brain damaged: RBD) who had suffered strokes. Our analysis was sensitive to the presence of neglect on the cube (i.e., missing left sided details) with voxel-wise lesion symptom mapping (VLSM) highlighting involvement of expected brain regions (superior temporal and supramarginal gyri). With left-sided omissions removed from analyses, we failed to find any difference between LBD and RBD patients. While the presence of left neglect appeared to exaggerate errors, this was only significant for errors of scale and proportion for the star drawing. VLSM of the distinct error domains demonstrated white matter involvement (and a minor contribution from the right insula) with respect to scale errors of the cube only. Finally, blinded judgements of hemisphere of lesion based on qualitative assessment of the drawings were no better than chance. These results suggest that figure copying is a complex task relying on large scale neural networks involving both hemispheres. Clearly, models of visuoconstructional capacity that emphasise right hemisphere dominance are not entirely accurate.

Boredom is a common experience, prevalent in neurological and psychiatric populations, yet its cognitive characteristics remain poorly understood. We explored the relationship between boredom proneness, sustained attention and adult symptoms of attention deficit hyperactivity disorder (ADHD). The results showed that high boredom-prone individuals (HBP) performed poorly on measures of sustained attention and showed increased symptoms of ADHD and depression. The results also showed that HBP individuals can be characterised as either apathetic-in which the individual is unconcerned with his/her environment, or as agitated-in which the individual is motivated to engage in meaningful activities, although attempts to do so fail to satisfy. Apathetic boredom proneness was associated with attention lapses, whereas agitated boredom proneness was associated with decreased sensitivity to errors of sustained attention, and increased symptoms of adult ADHD. Our results suggest there is a complex relationship between attention and boredom proneness.

Boredom is a ubiquitous human experience that can best be described as an inability to engage with one's environment despite the motivation to do so. Boredom is perceived as a negative experience and demonstrates strong associations with other negatively valenced states including depression and aggression. Although boredom has been shown to be elevated in neurological and psychiatric illnesses, little is known about the neural underpinnings of the state. We scanned the brains of healthy participants under four separate conditions: a resting state scan, a sustained attention task and two video-based mood inductions, one known to produce boredom and another we validated to produce a state of interest or engagement. Using independent components analyses, results showed common regions of correlated activation in posterior regions of the so-called default mode network (DMN) of the brain across all four conditions. The sustained attention and boredom induction scans were differentiated from the resting state scan by the presence of anticorrelated activity-i.e. when DMN regions were active, this region was deactivated-in the anterior insula cortex. This same region demonstrated correlated activity with both the DMN and the regions associated with attentional control during the interest mood induction. We interpret these findings to suggest that boredom represents a failure to engage executive control networks when faced with a monotonous task-in other words, when the task demands some level of engagement (watch the movie, search for infrequent targets), but is so mundane that attempts to do so fail.

Our behavior is predicated on mental models of the environment that must be updated to accommodate incoming information. We had 13 right-brain-damaged (RBD) patients and 10 left-brain-damaged (LBD) patients play the children's game "rock, paper, scissors" against a computer opponent that covertly altered its strategy. Healthy age-matched controls and LBD patients quickly detected extreme departures from uniform play ("paper" chosen on 80% of trials), but the RBD patient group did not. Seven RBD patients presented with neglect and although this was associated with greater impairment in strategy updating, there were exceptions: 2 of 7 neglect patients performed above the median of the patient group and 1 of the 6 nonneglect participants was severely impaired. Although speculative, lesion analyses contrasting high and low performing patients showed that severe impairments were associated with insula and putamen lesions. Interestingly, relative to the controls, the LBD group tended to "maximize" choices in the strongly biased condition (i.e., optimal strategy chosen on 100% of the trials), whereas controls "matched" the computer's strategy (i.e., optimal strategy chosen on 80% of the trials). We conclude that RBD leads to impaired updating of mental models to exploit environmental changes.

Judgments of spatial relationships are often made when the object or observer is moving. Behaviourally, there is evidence that these 'dynamic' judgments of spatial extent differ from static judgments. For example, in one of the simplest probes of spatial extent--the line bisection task--the typically observed leftward bisection bias of about 1% of line length is increased considerably after left-to-right scanning. Here we used fMRI to examine whether or not different brain regions would be involved in static and dynamic judgments of spatial extent. Dynamic (i.e., scan the line prior to bisecting) relative to static ocular bisections (i.e., line bisection by fixation) produced activations in the cuneus and precuneus bilaterally, with reduced activation relative to static judgments observed in the supramarginal gyrus bilaterally. Dynamic bisections relative to a control condition (i.e., scan a line and then saccade to a transection mark) produced activations in the precuneus/superior parietal lobe bilaterally and left cerebellum. Only marginal evidence was found for different activations due to the initial scan direction of the line. These results highlight the fact that dynamic judgments of spatial extent use distinct brain regions from those employed to make static judgments, and the same mechanism is employed independent of scan direction. It may be the case that velocity processing and time estimates are integrated primarily in the cuneus and precuneus to produce estimates of spatial extent under dynamic scanning conditions.

International audience; ''Schizophrenia patients demonstrate behavioural and cerebral lateralised anomalies, prompting some authors to suggest they exhibit a mild form of right unilateral neglect. To better describe and understand lateralised visuospatial anomalies in schizophrenia, three experiments were run using tasks often utilised to study visuospatial processing in healthy individuals and in neglect patients: the Behavioural Inattention Test (BIT), the manual line bisection task with and without a local cueing paradigm, the landmark task (or line bisection judgement), and the number bisection task. Although the schizophrenia patients did not exhibit the full-blown neglect syndrome, they did demonstrate marked spatial biases that differentiated them from controls on all but two tasks. More specifically, schizophrenia patients showed neither a simple perceptual deficit nor an asymmetry, but demonstrated (1) lateralised anomalies on a simple manual line bisection task; (2) unilateral attentional deficits for line bisection within a local cueing paradigm; and (3) a lateralised deficit in the visuospatial representations of numbers. Altogether, these results suggest a right hemineglect-like deficit in schizophrenia in attentional, representational, and motor-intentional processes. Yet it does not appear to be as strong a phenomenon. Indeed, it could be considered as an accentuation of the normal asymmetry in visuospatial processing.''

Prism adaptation reduces some symptoms of neglect; however the mechanisms underlying such changes are poorly understood. We suggest that prisms influence neglect by acting on dorsal stream circuits subserving visuomotor control, with little influence on perceptual aspects of neglect. We examined prism adaptation in three neglect patients and a group of healthy controls on line bisection and landmark tasks. Neglect patients showed a dramatic reduction in the rightward bias for line bisection, but absolutely no change in their leftward bias on the landmark task, which is a perceptual equivalent to bisection. However, in controls, prisms produced 'neglect-like' deficits on both the line bisection and landmark tasks. These data suggest that prisms influence visually guided actions more so than perception in neglect.

Recent concussion research has led to the development of computerized test batteries designed to measure working memory and psychomotor speed deficits in acute stage post-concussion. These tests lack a measure of motor control deficits, which may linger well after other symptoms have remitted. For athletes, this may mean returning to play while still uncoordinated or neurologically fragile. The present research involved the development of a visuomotor pointing task designed to induce a speed-accuracy trade off to measure motor planning and execution performance in concussed athletes. Data collected using this tool were contrasted with CogSport, a commercially available computerized test battery designed to assess residual cognitive effects of concussion in athletes. Results suggest that a motor task may be able to detect long-term effects of concussion not measurable with CogSport. If future research can confirm these findings, we suggest that a measure of motor control may need to be added to existing batteries to improve their sensitivity to long term effects.

Exposure to prisms has long been used to explore the control of visually guided actions primarily because adaptation requires the recalibration of misaligned reference frames due to perturbed visual input (i.e. eye-in-head and hand-centered reference frames must be realigned). To date, the only neuroimaging study to explore the direct effects of prisms on pointing used positron emission tomography and found increased activation only in right parietal cortex. We used event-related functional MRI to examine the effects of prisms on visuomanual pointing. Results demonstrated changes in activity in the anterior cingulate, the anterior intraparietal region and in a medial region of the right cerebellum. Specifically, activity in these regions was higher for the first few pointing trials made while viewing targets through prisms when directly contrasted to the last few trials. These results highlight that a more extensive network of cortical and cerebellar regions is involved in recalibrating visuomotor commands in the face of perturbed visual input.

Neuroimaging studies have demonstrated that heterotopic tissue of patients with "double cortex" is activated during motor and somatosensory tasks. Activation in patients with malformations of cortical development (MCD) has been variable, likely due to the heterogeneity of the disorder. We examined clinical, electroencephalography (EEG), neuropsychological, and functional MRI findings in a patient with intractable epilepsy secondary to MCD in the left temporal cortex. Invasive EEG monitoring revealed that the dysplastic tissue was not involved in ictal onset of seizures. Functional MRI tests of motion and object processing, memory encoding, and language demonstrated no activation within dysplastic tissue. Hemispheric asymmetries in activation for motion and object processing were evident, favoring the right hemisphere--a pattern not evident in controls. These weaker activations in the patient were present in tissue proximal to the seizure focus. Thus, nonepileptogenic dysplastic tissue may not support cognitive functions, with abnormal processing evident in epileptogenic tissue.

Several visuo-motor tasks can be used to demonstrate biases towards left hemispace in schizophrenic patients, suggesting a minor right hemineglect. Recent studies in neglect patients used a new number bisection task to highlight a lateralized defect in their visuo-spatial representation of numbers. To test a possible lateralized representational deficit in schizophrenia, we used the number bisection task in 11 schizophrenic patients compared to 11 healthy controls. Participants were required to orally indicate the central number of an interval orally presented. Whereas healthy subjects showed no significant bias, schizophrenic patients presented a significant leftward bias. Therefore, these results suggest an impairment in higher order representations of the number space in patients with schizophrenia, an impairment that is qualitatively similar to the deficit described in neglect patients.

It has been evident for some time that the Boredom Proneness Scale (BPS), a commonly used measure of trait boredom, does not constitute a single scale. Factor analytic studies have identified anything from two to seven factors, prompting Vodanovich and colleagues to propose an alternative two factor, short form version Boredom Proneness Scale-Short Form (BPS-SR). The present study further investigates the factor structure and validity of both the BPS and the BPS-SR. The two-factor solution obtained for the BPS-SR appears to be an artifact of item wording of reverse-scored items. These same items may also have contributed to the earlier complexity and inconsistency of results for the full BPS. An eight-item scale of only consistently worded items (i.e., those not requiring reverse scoring) was developed. This new scale demonstrated unidimensionality and the scale score had good internal consistency and construct validity comparable to the original BPS score.

We describe a set of Tufnel problems that arise when repeated use of a fixed-point scale precipitates failures to assess a full range of subjective experiences. As empirical evidence, participants in Study 1 periodically reported their depth of mind wandering on either 5- or 7-point Likert scales during a sustained attention task. The proportion of participants providing maximum scale ratings increased quickly over time-on-task and did so more quickly for the 5-point than for the 7-point group. Participants in Study 2 completed the same task using a 10-point scale before indicating whether and where they could have used a scale extended to "11" during the task. Slightly more than 20% of participants reported needing a scale extension. This Need for 11 was associated with differences in both reports of mind wandering depth and task performance. We conclude that Tufnel problems warrant methodological consideration and reflect interesting constraints on human judgment.

Boredom is a common experience in healthy individuals and may be elevated in various neurological or psychiatric conditions. As yet, very little is known about the cognitive or neural bases of the subjective experience of boredom. We examined temporal perception and the temporal allocation of attention in healthy individuals reporting high- or low-levels of boredom. We found no difference in high- or low-boredom-prone individuals in the temporal allocation of attention, while individuals who experienced low-levels of boredom tended to underestimate time more so than high-boredom-prone individuals. Furthermore, high-boredom-prone individuals demonstrated higher error values when estimating time indicating that the subjective perception of the passage of time may be a critical component to the experience of boredom.

Many recent models of schizophrenia have attempted to explain the so-called first-rank symptoms in terms of a breakdown in the self-monitoring of thoughts and behaviours. These models have focused on the most common symptom of schizophrenia auditory hallucinations-suggesting that they may represent disordered self-monitoring of internal speech. As such, much attention has been given to the role of the temporal and frontal cortices in the clinical presentation of patients with schizophrenia. In this review, we examine the role of the posterior parietal cortex (PPC) in schizophrenia within the context of recent models of self-monitoring deficits in these patients. Attentional dysfunctions and certain impairments of motor control and motor imagery all point towards the involvement of the parietal cortex in the disorder. In particular, we suggest that patients experiencing passivity phenomena (e.g., delusions of control) may have particular impairments of parietal function related to poor utilisation of forward models of intended actions. We also present a novel hypothesis that suggests differential impairments of the left and right parietal cortices in schizophrenia may help explain many of the first-rank symptoms of the disorder.

Background. It has been argued recently that the attentional dysfunction in schizophrenia occurs as a result of an inability to inhibit automatic attentional shifts to compelling external stimuli. However, this hypothesis is based on performance on paradigms that require overt or covert shifts of spatial attention.Method. We investigated responses to foveally presented stimuli in patients with schizophrenia and healthy controls as they performed unidimensional and bidimensional versions of the flanker task. In both tasks, centrally presented target stimuli were flanked by peripheral stimuli that were either congruent or incongruent with the behavioural goal of the subject. In the bidimensional task, the flanking stimuli could be congruent and incongruent on multiple stimulus characteristics.Results. On the unidimensional flanker task, the behavioural goal modulated the responses of the schizophrenia group such that response times (RTs) to target stimuli that were flanked by congruent stimuli were faster than RTs to target stimuli flanked by incongruent stimuli. However, on the bidimensional flanker task, the responses of schizophrenia patients were no longer constrained by the behavioural goal and RTs to both congruent and incongruent stimuli were equivalent.Conclusions. It appears that the attentional dysfunction in schizophrenia may reflect difficulty in resolving multiple and simultaneous response conflicts. These findings suggest a possible role for the anterior cingulate cortex in the attentional impairments associated with schizophrenia.

Using variants of a visually guided pointing task, in which subjects make pointing movements towards targets of varying sizes, we explored motor imagery in a patient with visual neglect. When this patient actually pointed towards targets of different sizes he showed the normal correlation between movement duration (MD) and target size, such that MD increased as target size decreased. In contrast, his imagined movements did not show the same speed-accuracy trade-off observed for actual movements. This was true regardless of the hand used or the initial direction of movement (left versus right). The patient performed normally on several tasks of visual imagery, including size estimation, perceptual discrimination and localization of cities on an imagined map. This patient's performance suggests that the networks in the right parietal lobe play an important role in the generation of internal models of motor movements regardless of the hand used to perform the task.

Recent work has shown that pictorial illusions have a greater effect on perceptual judgements than they do on the visual control of actions, such as object-directed grasping. This dissociation between vision for perception and vision for action is thought to reflect the operation of two separate streams of visual processing in the brain. Glover and Dixon claim, however, that perceptual illusions can influence the control of grasping but that these effects are evident only at early stages of the movement. By the time the action nears its completion any effect of illusions disappears. Glover and Dixon suggest that these results are consistent with what they call a 'planning and control' model of action, in which actions are planned using a context-dependent visual representation but are monitored and corrected online using a context-independent representation. We reanalysed data from an earlier experiment on grasping in the Ebbinghaus illusion in which we showed that maximum grip aperture was unaffected by this size-contrast illusion. When we looked at these data more closely, we found no evidence for an effect of the illusion even at the earliest stages of the movement. These findings support the suggestion that the initial planning of a simple object-directed grasping movement in this illusory context is indeed refractory to the effects of the illusion. This is not to suggest that more deliberate and/or complex movements could not be influenced by contextual information.

Right brain damaged patients show impairments in sequential decision making tasks for which healthy people do not show any difficulty. We hypothesized that this difficulty could be due to the failure of right brain damage patients to develop well-matched models of the world. Our motivation is the idea that to navigate uncertainty, humans use models of the world to direct the decisions they make when interacting with their environment. The better the model is, the better their decisions are. To explore the model building and updating process in humans and the basis for impairment after brain injury, we used a computational model of non-stationary sequence learning. RELPH (Reinforcement and Entropy Learned Pruned Hypothesis space) was able to qualitatively and quantitatively reproduce the results of left and right brain damaged patient groups and healthy controls playing a sequential version of Rock, Paper, Scissors. Our results suggests that, in general, humans employ a sub-optimal reinforcement based learning method rather than an objectively better statistical learning approach, and that differences between right brain damaged and healthy control groups can be explained by different exploration policies, rather than qualitatively different learning mechanisms.

Competing visual stimuli lead to slower responses to targets. This response competition must be resolved before correct responses are executed. Neuroimaging suggests that response competition monitoring may be subserved by an integrated neural network including the anterior cingulate cortex (ACC). In this study, 1 patient with a parietal lesion (Patient J.S.) and 1 with an ACC lesion (Patient G.M.) were presented with 2 flanker tasks; 1 required verbal identification of color targets, and the other required an opposite response to targets (e.g., see red and say "green"); a control group was also tested. For controls, perceptually incongruent flankers interfered with the ability to inhibit prepotent responses to targets. Patient J.S. performed in a similar manner, even when flankers appeared in the neglected field. Patient G.M. demonstrated reduced interference effects for contralesional flankers. Results are discussed in terms of goal-directed selective attention and response competition monitoring.

Background. Abnormal performance on the antisaccade task suggests that patients with schizophrenia have difficulty with the inhibition of reflexive attentional shifts. The aim of the study was to investigate whether deficits in the inhibition of reflexive attentional shifts were specific to the oculomotor modality or whether they could also occur when attentional shifts were made without eye movements (e.g. covert attentional shifts).Methods. Fifteen medicated patients with chronic schizophrenia and 15 matched controls performed the antisaccade task and the covert orientating task (COVAT) where the probability of targets appearing at the same location of a peripheral cue was varied so that voluntary and reflexive orientating systems had the same goal (80% probability of target and cued condition) or opposite goals (20%probability of target at cued location). A condition where only reflexive orientating was initiated was also included (50% probability of target at cued location). For each of these conditions the stimulus onset asynchrony (SOA) varied between 150 and 350 ms.Results. Patients with schizophrenia showed normal latency and accuracy for visually guided saccades but increased error rates and latency on the antisaccade task. For the COVAT, patients with schizophrenia were unable to use voluntary orientating strategies to inhibit reflexive shifts of covert attention. On conditions where only reflexive orientating was required or when the goals of the reflexive and voluntary orientating systems were the same, patients with schizophrenia showed normal performance.Conclusions. These results suggest the reflexive orientating mode is normal in patients with chronic schizophrenia. However, these patients have a reduced ability to utilize the voluntary orientating mode to control or inhibit reflexive orientating. This impairment of voluntary control is evident for both overt and covert attentional shifts.

Processes of covert visual spatial attention have been closely linked to the programming of saccadic eye movements. In particular, it has been hypothesized that the reduction in saccadic latency that occurs in the gap paradigm is due to the prior disengagement of covert visual spatial attention. This explanation has received considerable criticism. No study as yet has attempted to demonstrate a facilitation of the disengagement of attention from a covertly attended object. If such facilitation were possible, it would support the hypothesis that the predisengagement of covert attention is necessary for the generation of express saccades. In two experiments using covert orienting of visual attention tasks (COVAT), with a high probability that targets would appear contralateral to the cued location, we attempted to facilitate the disengagement of covert attention by extinguishing peripheral cues prior to the appearance of targets. We hypothesized that the gap between cue offset and target onset would facilitate disengagement of attention from a covertly attended object. For both experiments, responses to targets appearing after a gap were slower than were responses in the no-gap condition. These results suggest that the prior offset of a covertly attended object does not facilitate the disengagement of attention.

Objective: Patients with visual extinction have difficulty detecting a single contralesional stimulus when a second stimulus is simultaneously presented on the ipsilesional side. The rarely reported phenomenon of visual anti-extinction describes the opposite behavior, in which patients show greater difficulty in reporting a stimulus presented in isolation than they do in reporting 2 simultaneously presented stimuli. S. J. Goodrich and R. Ward (1997, Anti-extinction following unilateral parietal damage, Cognitive Neuropsychology, Vol. 14, pp. 595–612) suggested that visual anti-extinction is the result of a taskspecific mechanism in which processing of the ipsilesional stimulus facilitates responses to the contralesional stimulus; in contrast, G. W. Humphreys, M. J. Riddoch, G. Nys, and D. Heinke (2002, Transient binding by time: Neuropsychological evidence from anti-extinction, Cognitive Neuropsychology, Vol. 19, pp. 361–380) suggested that temporal binding groups contralesional and ipsilesional stimuli together at brief exposure durations. Method: We investigated extinction and anti-extinction phenomena in 3 brain-damaged patients using an extinction paradigm in which the stimulus exposure duration was systematically manipulated. Results: Two patients showed both extinction and anti-extinction depending on the exposure duration of stimuli. Data confirmed the crucial role of duration in modulating the effect of extinction and anti-extinction. However, contrary to Humphreys and colleagues’ (2002) single case, our patients showed extinction for short and anti-extinction for long exposure durations, suggesting that different mechanisms might underlie our patients’ pattern of data. Conclusion: We discuss a novel “attentional waiting” hypothesis, which proposes that anti-extinction may be observed in patients showing extinction if the exposure duration of stimuli is increased.

Studies using visual illusions to demonstrate a dissociation within the visual system can provide relevant and decisive data only if certain methodological points are taken into account. Although, our previous work (Stottinger et al. in Exp Brain Res 202:88–97, 2010) followed these points, the task made use of only 2-D stimuli which may raise doubts concerning the nature of grasping in that experiment. We therefore replicated the study using a 3-D version of the empty space illusion. Consistent with the earlier study, that used 2-D stimuli, we found that grip aperture followed actual target size independent of illusory effects, while perceived length, as indicated by finger-thumb span, clearly was subject to the illusion. Therefore, the prior results cannot be due to the use of 2-D stimuli. Together, these two studies provide clear evidence for the perception versus action hypothesis.

The line bisection task is used as a bedside test of spatial neglect patients who typically bisect lines to the right of true centre. To disambiguate the contribution of perceptual from motor biases in bisection, previous research has used the landmark task in which participants determine whether a transection mark is left or right of centre. One recent study using stimuli that reliably leads to leftward perceptual biases in healthy individuals, found that ocular judgements of centre were biased to the right of centre, whereas manual bisections were biased leftwards. Here we used behavioural measures and functional MRI in healthy individuals to investigate ocular and perceptual judgements of centre. Ocular judgements were made by having participants fixate the centre of a horizontal bar that was dark at one end and light at the other (i.e., a ‘greyscale’ stimulus), whereas perceptual responses were made by having participants indicate whether a transection mark on the greyscales stimuli was to the left or right of centre. Behavioural data indicated a leftward bias in the first, second and longest fixations for bisection. Moreover, greyscale orientation (i.e., dark extremity to the right or to the left), and stimulus position modulated fixations. In contrast, for the landmark task, initial fixations were attracted towards the transection mark, whereas subsequent fixations were closer to veridical centre. Imaging data showed a large bilateral network, including superior parietal and lingual cortex, that was active for bisection. The landmark task activated a predominantly right hemisphere network including superior and inferior parietal cortices. Taken together these results indicate that very different strategies and underlying neural networks are invoked by the bisection and landmark tasks.

The superior parietal cortex is critical for the control of visually guided actions. Research suggests that visual stimuli relevant to actions are preferentially processed when they are in peripersonal space. One recent study demonstrated that visually guided movements towards the body were more impaired in a patient with damage to superior parietal cortex. Whereas past studies have explored disordered movement in optic ataxic patients, there has been less exploration of space perception in terms of search capacity in this population. In addition, there is some debate concerning the relationship between deficits of visuomotor control and impaired attention/perception in optic ataxia. Given that the dorsal stream has been implicated in the spatial processing of stimuli in peripersonal space, and damage to this region is known to cause optic ataxia, we felt that further investigation was warranted. We examined tactile search behavior in the fronto-parallel and radial planes in a patient with right superior parietal damage and optic ataxia. We used a pegboard with removable cylindrical pegs that allowed for the reorganization of targets between trials. To better characterize three-dimensional search behavior, we included both horizontal and vertical search conditions. Results showed that the patient spent more time searching, was more accurate and revisited more targets in right versus left space. Interestingly, the patient spent the majority of her time specifically searching the lower right quadrant of the stimulus array. Further analysis revealed lower target detection rates along the outer borders of the pegboard on all sides. The search pattern observed here is unusual considering that all targets were within arm's reach. The present experiment demonstrates that damage to superior parietal cortex impairs tactile search and biases exploration towards lower right peripersonal space.

The line bisection task--commonly used as a clinical measure of unilateral neglect--requires participants to place a mark on a horizontal line to indicate where they think centre is. In general, results suggest that the allocation of attention mediates bisection. In addition, previous research shows that participants rarely explore the endpoints of lines, suggesting that peripheral visual information informs bisection. Here, we examined bisection performance under conditions in which differing levels of 'noise' were introduced to the line to examine the hypothesis that the fidelity and symmetry of peripheral information would inform performance. Contrary to our expectations, results showed that symmetrically introducing noise to the line biased bisection further leftward compared to a 'no-noise' condition. Furthermore, asymmetrical noise increased leftward bisection errors primarily when lines were presented in left space or when the greater amount of noise was on the left half of the line. These results indicate that the fidelity of peripheral visual information mediates bisection behaviour that is already biased leftwards probably due to right hemisphere attentional mechanisms.