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In this paper, we present a review of how the various aspects of any study using an eye tracker (such as the instrument, methodology, environment, participant, etc.) affect the quality of the recorded eye-tracking data and the obtained eye-movement and gaze measures. We take this review to represent the empirical foundation for reporting guidelines of any study involving an eye tracker. We compare this empirical foundation to five existing reporting guidelines and to a database of 207 published eye-tracking studies. We find that reporting guidelines vary substantially and do not match with actual reporting practices. We end by deriving a minimal, flexible reporting guideline based on empirical research (Section “An empirically based minimal reporting guideline”).

Objectives Sensorimotor difficulties are often reported in autism spectrum disorders (ASD). Visual and motor skills are linked in that the processing of visual information can help in guiding motor movements. The present study investigated oculomotor skill and its relation to general motor skill in ASD by providing a comprehensive assessment of oculomotor control. Methods Fifty children (25 ASD; 25 typically developing [TD]), aged 7–10 years, completed a motor assessment (comprising fine and gross motor tasks) and oculomotor battery (comprising fixation, smooth pursuit, prosaccade and antisaccade tasks). Results No group differences were found for antisaccade errors, nor saccade latencies in prosaccade and antisaccade tasks, but increased saccade amplitude variability was observed in children with ASD, suggesting a reduced consistency in saccade accuracy. Children with ASD also demonstrated poorer fixation stability than their peers and spent less time in pursuit of a moving target. Motor skill was not correlated with saccade amplitude variability. However, regression analyses revealed that motor skill (and not diagnosis) accounted for variance in fixation performance and fast smooth pursuit. Conclusions The findings highlight the importance of considering oculomotor paradigms to inform the functional impact of neuropathologies in ASD and also assessing the presentation of co-occurring difficulties to further our understanding of ASD. Avenues for future research are suggested.

In this study, we seek to exclude other pathophysiological mechanisms by whichFrmd7knock-down may cause Idiopathic Infantile Nystagmus (IIN) using theFrmd7.tm1aandFrmd7.tm1bmurine models. We used a combination of genetic, histological and visual function techniques to characterize the role ofFrmd7gene in IIN using a novel murine model for the disease. We demonstrate that theFrmd7.tm1ballele represents a more robust model ofFrmd7knock-out at the mRNA level. The expression ofFrmd7was investigated using both antibody staining and X-gal staining confirming previous reports thatFrmd7expression in the retina is restricted to starburst amacrine cells and demonstrating that X-gal staining recapitulates the expression pattern in this model. Thus, it offers a useful tool for further expression studies. We also show that gross retinal morphology and electrophysiology are unchanged in theseFrmd7mutant models when compared with wild-type mice. High-speed eye-tracking recordings ofFrmd7mutant mice confirm a specific horizontal optokinetic reflex defect. In summary, our study confirms the likely role forFrmd7in the optokinetic reflex in mice mediated by starburst amacrine cells. We show that theFrmd7.tm1bmodel provides a more robust knock-out than theFrmd7.tm1amodel at the mRNA level, although the functional consequence is unchanged. Finally, we establish a robust eye-tracking technique in mice that can be used in a variety of future studies using this model and others. Although our data highlight a deficit in the optiokinetic reflex as a result of the starburst amacrine cells in the retina, this does not rule out the involvement of other cells, in the brain or the retina whereFrmd7is expressed, in the pathophysiology of IIN.

Two visual world eye-tracking experiments investigated anticipatory looks to implicit causes and implicit consequences in two clause sentences with mental state verbs (Stimulus-Experiencer and Experiencer-Stimulus) in the first main clause, and an explicit cause or consequence in the second. The first experiment showed that, just as when all continuations are causes, people look early at the implicit cause, when all continuations are consequences they look early at the implicit consequence, for the same verbs. When causes and consequences are intermixed, people direct their looks at the cause or consequence on a trial-by-trial basis depending on the connective (“because” or “and so”). Numerically, causes were favored overall, even when all the endings were consequences, but the effect was only significant at the end of the sentences in Experiment 2. The results are discussed in terms of rapid deployment of causal and consequential information implicit in mental state verbs, and in relation to conflicting accounts of why causes or consequences might generally be favored.

Some aspects of saccadic performance have been found to be abnormal in chronic schizophrenia. The majority of this research has, however, been performed on patients treated with long-term antipsychotic medication. Very few studies have examined saccadic performance in antipsychotic-naïve/free patients. There are also very few studies describing the relationship between saccadic performance and clinical symptoms, particularly in antipsychotic free patients. In this study, we compared pro and antisaccade performance in a large sample of antipsychotic-naïve/free schizophrenia patients (N = 45) with healthy controls (N = 57). Clinical symptoms were assessed using Scale for Assessment of Positive Symptoms (SAPS) and Negative Symptoms (SANS). In the antisaccade task, patients made significantly more errors, and their correct antisaccades had smaller amplitudes in comparison to healthy controls. Higher error rates were associated with increased severity of hallucinations. In the prosaccade task, patients had less accurate final eye positions, and made saccades with slower latency and reduced amplitude compared to the healthy controls. These observations in schizophrenia patients without the potential confounds of antipsychotic treatment suggest intrinsic link between saccadic deficits and schizophrenia pathogenesis. The relationship between antisaccade errors and hallucination severity supports the potential link between hallucinations and deficits in inhibitory control.

Obsessive-Compulsive Disorder (OCD) is characterized by abnormalities in the cortico-striato-thalamo-cortical (CSTC) circuitry of the brain. Antisaccade eye movement tasks measure aspects of the voluntary control of behaviour that are sensitive to CSTC circuitry dysfunction.In this study, we examined antisaccade eye movement parameters of OCD patients in comparison with healthy controls (HC). In addition, we also examined the relationship between the antisaccade eye movement parameters and the severity of OCD. Antisaccade performance among right handed OCD patients (N = 65) was compared to matched right handed HC (N = 57). Eye tracking data during the task performance were collected using an Eye-Link eye-tracker at 1000-Hz sampling rate. OCD symptom severity was evaluated using Yale-Brown obsessive compulsive scale.The antisaccade error percentage was significantly greater in OCD patients than HC (p0.001). In addition, OCD patients had less accurate final eye position compared to HC (p0.001). There were no significant correlation between antisaccade parameters and OCD severity measures.Deficient performance in antisaccade task supports CSTC abnormality in OCD and this appears to be independent of the illness severity. Examining this in remitted participants with OCD and in unaffected first degree relatives could help ascertaining their endophenotype validity.

Background: Deficient prefrontal cortex inhibitory control is of particular interest with regard to the pathogenesis of auditory hallucinations (AHs) in schizophrenia. Antisaccade task performance is a sensitive index of prefrontal inhibitory function and has been consistently found to be abnormal in schizophrenia. Methods: This study investigated the effect of transcranial direct current stimulation (tDCS) on antisaccade performance in 13 schizophrenia patients. Results: The tDCS resulted in significant reduction in antisaccade error percentage ( t = 3.4; P = 0.005), final eye position gain ( t = 2.3; P = 0.042), and AHs severity ( t = 4.1; P = 0.003). Conclusion: Our results raise the possibility that improvement in antisaccade performance and severity of AH may be mechanistically related.

In this study we investigated effects of the APOE ε4 allele (which confers an enhanced risk of poorer cognitive ageing, and Alzheimer’s Disease) on sustained attention (vigilance) performance in young adults using the Rapid Visual Information Processing (RVIP) task and event-related fMRI. Previous fMRI work with this task has used block designs: this study is the first to image an extended (6-minute) RVIP task. Participants were 26 carriers of the APOE ε4 allele, and 26 non carriers (aged 18–28). Pupil diameter was measured throughout, as an index of cognitive effort. We compared activity to RVIP task hits to hits on a control task (with similar visual parameters and response requirements but no working memory load): this contrast showed activity in medial frontal, inferior and superior parietal, temporal and visual cortices, consistent with previous work, demonstrating that meaningful neural data can be extracted from the RVIP task over an extended interval and using an event-related design. Behavioural performance was not affected by genotype; however, a genotype by condition (experimental task/control task) interaction on pupil diameter suggested that ε4 carriers deployed more effort to the experimental compared to the control task. fMRI results showed a condition by genotype interaction in the right hippocampal formation: only ε4 carriers showed downregulation of this region to experimental task hits versus control task hits. Experimental task beta values were correlated against hit rate: parietal correlations were seen in ε4 carriers only, frontal correlations in non-carriers only. The data indicate that, in the absence of behavioural differences, young adult ε4 carriers already show a different linkage between functional brain activity and behaviour, as well as aberrant hippocampal recruitment patterns. This may have relevance for genotype differences in cognitive ageing trajectories.

Children with Developmental Coordination Disorder (DCD) fail to acquire adequate motor skill, yet surprisingly little is known about the oculomotor system in DCD. Successful completion of motor tasks is supported by accurate visual feedback. The purpose of this study was to determine whether any oculomotor differences can distinguish between children with and without a motor impairment. Using eye tracking technology, visual fixation, smooth pursuit, and pro‐ and anti‐saccade performance were assessed in 77 children that formed three groups: children with DCD (aged 7–10), chronologically age (CA) matched peers, and a motor‐match (MM) group (aged 4–7). Pursuit gain and response preparation in the pro‐ and anti‐saccade tasks were comparable across groups. Compared to age controls, children with DCD had deficits in maintaining engagement in the fixation and pursuit tasks, and made more anti‐saccade errors. The two typically developing groups performed similarly, except on the fast speed smooth pursuit and antisaccade tasks, where the CA group outperformed the younger MM group. The findings suggest that children with DCD have problems with saccadic inhibition and maintaining attention on a visual target. Developmental patterns were evident in the typically developing groups, suggesting that the pursuit system and cognitive control develop with age. This study adds to the literature by being the first to systematically identify specific oculomotor differences between children with and without a motor impairment. Further examination of oculomotor control may help to identify underlying processes contributing to DCD. A video abstract of this article can be viewed at: https://youtu.be/NinXa2KlB4M. [Correction added on 27 January 2017, after first online publication: The video abstract link was added.]

Across three experiments we sought to determine whether extrafoveally presented emotional faces are processed sufficiently rapidly to influence saccade programming. Two rectangular targets containing a neutral and an emotional face were presented either side of a central fixation cross. Participants made prosaccades towards an abrupt luminosity change to the border of one of the rectangles. The faces appeared 150 ms before or simultaneously with the cue. Saccades were faster towards cued rectangles containing emotional compared to neutral faces even when the rectangles were positioned 12 degrees from the fixation cross. When faces were inverted, the facilitative effect of emotion only emerged in the −150 ms SOA condition, possibly reflecting a shift from configural to featural face processing. Together the results suggest that the human brain is highly specialized for processing emotional information and responds very rapidly to the brief presentation of expressive faces, even when these are located outsi...

Visuo-spatial representations of the alphabet (so-called 'alphabet forms') may be as common as other types of sequence-space synaesthesia, but little is known about them or the way they relate to implicit spatial associations in the general population. In thefirst study, we describe the characteristics of a large sample of alphabet forms visualized by synaesthetes. They most often run from left to right and have salient features (e.g., bends, breaks) at particular points in the sequence that correspond to chunks in the 'Alphabet Song' and at the alphabet mid-point. The Alphabet Song chunking suggests that the visuo- spatial characteristics are derived, at least in part, from those of the verbal sequence learned earlier in life. However, these synaesthetes are no faster at locating points in the sequence (e.g., what comes before/after letter X?) than controls. They tend to be more spatially consistent (measured by eye tracking) and letters can act as attentional cues to left/right space in synaesthetes with alphabet forms (measured by saccades), but not in non-synaesthetes. This attentional cueing suggests dissociation between numbers (which reliably act as attentional cues in synaesthetes and non-synaesthetes) and letters (which act as attentional cues in synaesthetes only).

Pupils dilate to a greater extent when participants view old compared to new items during recognition memory tests. We report three experiments investigating the cognitive processes associated with this pupil old/new effect. Using a remember/know procedure, we found that the effect occurred for old items that were both remembered and known at recognition, although it was attenuated for known compared to remembered items. In Experiment 2, the pupil old/new effect was observed when items were presented acoustically, suggesting the effect does not depend on low-level visual processes. The pupil old/new effect was also greater for items encoded under deep compared to shallow orienting instructions, suggesting it may reflect the strength of the underlying memory trace. Finally, the pupil old/new effect was also found when participants falsely recognized items as being old. We propose that pupils respond to a strength-of-memory signal and suggest that pupillometry provides a useful technique for exploring the underlying mechanisms of recognition memory.

Neuroimaging studies have shown the left temporal lobe to be important for contextual sentence integration. This study used single-pulse transcranial magnetic stimulation (TMS) to establish stronger causal evidence for the role of this brain region and also explored the involvement of the same cortical region in the right hemisphere (RH). In a semantic decision task, sentences with different cloze probability endings (highly expected, unexpected, and semantically anomalous) were presented to 59 participants. Single-pulse TMS was applied to the left or the right posterior temporal lobe. Vertex stimulation served as a baseline. Left temporal stimulation decelerated responses to expected and unexpected endings in a sentence-integration task. RH stimulation did not affect the responses. These results support the causal role of the left temporal lobe in semantic integration. Single-pulse TMS can contribute to a better understanding of language organization at a sentence level.

Neuregulin-1 (NRG-1) is a putative susceptibility gene for schizophrenia but the neurocognitive processes that may involve NRG-1 in schizophrenia are unknown. Deficits in antisaccade (AS) and smooth pursuit eye movements (SPEM) are promising endophenotypes, which may be associated with brain dysfunctions underlying the pathophysiology of schizophrenia. The aim of this study was to investigate the associations of NRG-1 genotypes with AS and SPEM in schizophrenia patients and healthy controls. Patients (N = 113) and controls (N = 106) were genotyped for two NRG-1 single nucleotide polymorphisms (SNPs); SNP8NRG222662, a surrogate marker for the originally described Icelandic NRG-1 risk haplotype, and SNP8NRG243177, which has recently been associated with individual differences in brain function. Subjects underwent infrared oculographic assessment of AS and SPEM. The study replicates previous findings of impaired AS and SPEM performance in schizophrenia patients (all P < 0.005; all d = 0.5-1.5). SNP8NRG243177 risk allele carriers had marginally increased variability of AS spatial error (P = 0.050, d = 0.3), but there were no significant genotype effects on other eye movement variables and no significant diagnosis-by-genotype interactions. Generally, risk allele carriers (G allele for SNP8NRG222662 and T allele for SNP8NRG243177) had numerically worse performance than non-carriers on most AS and SPEM variables. The results do not suggest that NRG-1 genotype significantly affects AS and SPEM task performance. However, the power of the sample to identify small effects is limited and the possibility of a type II error must be kept in mind. Larger samples may be needed to reliably investigate such gene effects on oculomotor endophenotypes.

The saccadic eye movement system provides researchers with a powerful tool with which to explore the cognitive control of behaviour. It is a behavioural system whose limited output can be measured with exceptional precision, and whose input can be controlled and manipulated in subtle ways. A range of cognitive processes (notably those involved in working memory and attention) have been shown to influence saccade parameters. Researchers interested in the relationship between cognitive function and psychiatric disorders have made extensive use of saccadic eye movement tasks to draw inferences as to the cognitive deficits associated with particular psychopathologies. The purpose of this review is to provide researchers with an overview of the research literature documenting cognitive involvement in saccadic tasks in healthy controls. An appreciation of this literature provides a solid background against which to interpret the deficits on saccadic tasks demonstrated in patient populations.

BackgroundIn first-episode schizophrenia, longer duration of untreated psychosis (DUP) predicts poorer outcomes.AimsTo address whether the relationship between DUP and outcome is a direct causal one or the result of association between symptoms and/or cognitive functioning and social functioning at the same time point.MethodSymptoms, social function and cognitive function were assessed in 98 patients with first-episode schizphrenia at presentation and 1 year later.ResultsThere was no significant clinical difference between participants with short and long DUP at presentation. Linear regression analyses revealed that longer DUP significantly predicted more severe positive and negative symptoms and poorer social function at 1 year, independent of scores at presentation. Path analyses revealed independent direct relationships between DUP and social function, core negative symptoms and positive symptoms. There was no significant association between DUP and cognition.ConclusionsLonger DUP predicts poor social function independently of symptoms. The findings underline the importance of taking account of the phenomenological overlap between measures of negative symptoms and social function when investigating the effects of DUP.

The role of the posterior parietal cortex in smooth pursuit eye movements remains unclear. We used low frequency repetitive transcranial magnetic stimulation (rTMS) to study the cognitive and neural systems involved in the control of smooth pursuit eye movements. Eighteen participants were tested on two separate occasions. On each occasion we measured smooth pursuit eye tracking before and after 6 min of 1 Hz rTMS delivered at 90% of motor threshold. Low frequency rTMS over the posterior parietal cortex led to a significant reduction in smooth pursuit velocity gain, whereas rTMS over the motor cortex had no effect on gain. We conclude that low frequency offline rTMS is a potentially useful tool with which to explore the cortical systems involved in oculomotor control.

BackgroundThe impact of co-morbid substance use in first-episode schizophrenia has not been fully explored.MethodThis naturalistic follow-up of a cohort of 152 people with first-episode schizophrenia examined substance use and clinical outcome in terms of symptoms and social and neuropsychological function.ResultsData were collected on 85 (56%) of the patient cohort after a median period of 14 months. Over the follow-up period, the proportion of smokers rose from 60% at baseline to 64%. While 30% reported lifetime problem drinking of alcohol at baseline, only 15% had problem drinking at follow-up. Furthermore, while at baseline 63% reported lifetime cannabis use and 32% were currently using the drug, by the follow-up assessment the latter figure had fallen to 18.5%. At follow-up, persistent substance users had significantly more severe positive and depressive symptoms and greater overall severity of illness. A report of no lifetime substance use at baseline was associated with greater improvement in spatial working memory (SWM) at follow-up.ConclusionsPast substance use may impede recovery of SWM performance in people with schizophrenia in the year or so following first presentation to psychiatric services. The prevalence of substance use other than tobacco tends to diminish over this period, in the absence of specific interventions. Persistent substance use in first-episode schizophrenia is associated with more severe positive and depressive symptoms but not negative symptoms, and should be a target for specific treatment intervention.

The antisaccade task provides a laboratory analogue of situations in which execution of the correct behavioural response requires the suppression of a more prepotent or habitual response. Errors (failures to inhibit a reflexive prosaccade towards a sudden onset target) are significantly increased in patients with damage to the dorsolateral prefrontal cortex and patients with schizophrenia. Recent models of antisaccade performance suggest that errors are more likely to occur when the intention to initiate an antisaccade is insufficiently activated within working memory. Nicotine has been shown to enhance specific working memory processes in healthy adults. MATERIALS AND METHODS: We explored the effect of nicotine on antisaccade performance in a large sample (N = 44) of young adult smokers. Minimally abstinent participants attended two test sessions and were asked to smoke one of their own cigarettes between baseline and retest during one session only. RESULTS AND CONCLUSION: Nicotine reduced antisaccade errors and correct antisaccade latencies if delivered before optimum performance levels are achieved, suggesting that nicotine supports the activation of intentions in working memory during task performance. The implications of this research for current theoretical accounts of antisaccade performance, and for interpreting the increased rate of antisaccade errors found in some psychiatric patient groups are discussed.

Aims: Many forms of human conditioned behaviour depend upon explicit knowledge of the predictive contingency between stimuli, responses and the reinforcer. However, it remains uncertain whether the conditioning of three key behaviours in drug addiction-selective attention, instrumental drug-seeking behaviour and emotional state-are dependent upon contingency knowledge. To test this possibility, we employed an avoidance procedure to generate rapidly these three forms of conditioned behaviour without incurring the methodological problems of drug conditioning. Design: In two experiments, participants (16 students) were trained on a schedule in which one stimulus (S +) predicted the occurrence of a startling noise, which could be cancelled by performing an instrumental avoidance response. Measurements : The allocation of attention to the S + and the rate and probability of the avoidance response in the presence of S + were measured. Following training, participants were tested for their knowledge of the stimulus-noise contingencies arranged in the study and rated the emotional qualities of the stimuli. Findings: Both experiments showed that S + gained control of selective attention, instrumental avoidance behaviour and subjective anxiety, but only in participants who reported explicit knowledge of the Pavlovian contingency between the S + and the startling noise. Conclusions: The implication of the present findings is that the control of selective attention, instrumental drug-seeking behaviour and emotional state by drug-paired stimuli is mediated by cognitive knowledge of the predictive contingency between the stimulus and the drug.

Attentional processes have traditionally been closely linked to the production of saccadic eye movements, but their role in the control of smooth pursuit eye movements remains unclear. In two experiments we used dual task paradigms to vary the attentional resources available for pursuit eye tracking. In both experiments we found that attentionally demanding secondary tasks impaired smooth pursuit performance, resulting in decreased velocity and increased position error. These findings suggest that attention is important for the maintenance of accurate smooth pursuit, and do not support the hypothesis that pursuit is a relatively automatic function that proceeds optimally in the absence of attentional control. These results add weight to the suggestion that a similar functional architecture underlies both pursuit and saccadic eye movements.

Objective: Little is known about factors that mediate adherence with medication during the early stages of antipsychotic treatment in schizophrenia. This study sought to identify factors that may be associated with medication adherence in first-episode schizophrenia. Method: In 101 patients, adherence was assessed along with potentially relevant variables, including attitudes toward medication, insight, substance misuse, side effects and psychopathology. Results: In a linear regression analysis, negative attitudes toward medication and a relative lack of insight contributed significantly towards poor adherence. Although poorly adherent patients had significantly higher scores on negative and disorganization syndromes, these did not contribute significantly towards adherence. Adverse medication side effects, subjective well-being and substance misuse showed no significant association with adherence. Conclusion: At the initiation of drug treatment, attitudes toward medication and insight appear more relevant to medication adherence than side effects. Adherence appears to reflect a complex interaction of influences, which may change over time.

This pilot study examines whether hormone therapy for breast cancer affects cognition. Patients participating in a randomised trial of anastrozole, tamoxifen alone or combined (ATAC) (n=94) and a group of women without breast cancer (n=35) completed a battery of neuropsychological measures. Compared with the control group, the patients were impaired on a processing speed task (p=0.032) and on a measure of immediate verbal memory (p=0.026) after controlling for the use of hormone replacement therapy in both groups. Patient group performance was not significantly related to length of treatment or measures of psychological morbidity. The results showed specific impairments in processing speed and verbal memory in women receiving hormonal therapy for the treatment of breast cancer. Verbal memory may be especially sensitive to changes in oestrogen levels, a finding commonly reported in studies of hormone replacement therapy in healthy women. In view of the increased use of hormone therapies in an adjuvant and preventative setting their impact on cognitive functioning should be investigated more thoroughly.

BackgroundMany studies have demonstrated early generalised cognitive impairment in schizophrenia.AimsTo examine executive function in first-episode schizophrenia, characterise the nature of the impairment and specify any relationships with symptoms and duration of untreated psychosis (DUP).MethodPatients (n=136) and normal controls (n=81) were assessed with the Cambridge Automated Neuropsychological Test Battery, National Adult Reading Test IQ, and Scales for the Assessment of Positive and Negative Symptoms.ResultsMemory and executive impairments in patients were independent of IQ level. Spatial working memory was impaired because of inadequate strategy use. On a planning task, patients showed reduced planning times and suboptimal problem-solving. On an attentional set-shifting task, 75% of patients were able to perform an extra-dimensional shift thought to be a core attribute of prefrontal cortex function. Those who failed had significantly longer DUP.ConclusionsPrefrontal cortex function deteriorates at the onset of psychosis and continues to worsen over time.

Recent accounts have proposed that orbitofrontal cerebral cortex mediates the control of behavior based on emotional feedback and its somatic correlates. Here, we describe the performance of a patient with circumscribed damage to orbitofrontal cortex during a task that requires switching between sensory-motor mappings, contingent on the occurrence of positive and negative reward feedbacks. In this test, normal subjects and other patients with prefrontal damage show an increase in latencies for eye movements towards locations at which a negative feedback was presented on the preceding trial. In contrast, our patient does not show this reward-dependent inhibition of return effect on saccades. She was also found to make an increased rate of ocular refixations during visual search and used a disorganized search strategy in a token foraging task. These findings suggest that orbital regions of the prefrontal cortex mediate an inhibitory effect on actions directed towards locations that have been subject to negative reinforcement. Further, this mechanism seems to play a role in controlling natural search and foraging behavior.

In the antisaccade paradigm, subjects are instructed to fixate a central point, and then move their eyes towards a position in space in the opposite direction but equidistant to a peripheral, sudden onset target. Antisaccade errors occur when subjects are “distracted” by the target and make a saccade towards it. These errors are more common in patients with schizophrenia but the underlying cause remains unclear. To determine whether antisaccade errors simply reflect a general inability to maintain fixation or are the consequence of a more specific deficit in the strategic control of internally generated actions, patients with first-episode schizophrenia and healthy controls performed three saccadic paradigms which shared the core feature of requiring a prepotent saccade to be suppressed, but varied in their concurrent cognitive demands. We found that both groups showed an increase in errors as the cognitive demands increased across task. However, this increase was significantly steeper in the schizophrenic patients than in the controls. We also found that schizophrenic patients were as able as controls to inhibit prepotent saccades towards a target in a paradigm with no other cognitive demands. Possible explanations of these results include reduced working memory resources and impaired motor preparation in schizophrenia.

OBJECTIVES: Research indicates that older adults’ (≥ 60 years) emotion recognition is worse than that of young adults, young and older men’s emotion recognition is worse than that of young and older women (respectively), older adults’ looking at mouths compared to eyes is greater than that of young adults. Nevertheless, previous research has not compared older men’s and women’s looking at emotion faces so the present study had two aims: (1) to examine whether the tendency to look at mouths is stronger amongst older men compared to older women, and (2) to examine whether men’s mouth looking correlates with better emotion recognition. METHOD: We examined the emotion recognition abilities, and spontaneous gaze patterns of young (n = 60) and older (n = 58) males and females as they labelled emotion faces. RESULTS: Older men spontaneously looked more to mouths than older women, and older men’s looking at mouths correlated with their emotion recognition, whereas women’s looking at eyes correlated with their emotion recognition. DISCUSSION: The findings are discussed in relation to a growing body of research suggesting both age and gender differences in response to emotional stimuli, and the differential efficacy of mouth and eyes looking for men and women.

Francisco Aboitiz*, F. Xavier Castellanos and Ximena Carrasco Departamento de Psiquiatria, Facultad de Medicina, and Centro Interdisciplinario de Neurociencia, Pontificia Universidad Catolica de Chile, Santiago, Chile New York University Child Study Center, Nathan Kline Institute for Psychiatric Research, New York, NY, USA Servicio de Neurologia y Psiquiatria infantil, Hospital Luis Calvo Mackenna Facultad de Medicina, Universidad de Chile, Santiago, Chile

Healthy individuals with high as compared to low levels of schizotypal personality traits make more first saccades to the left side of faces, suggesting increased right hemisphere (RH) dominance for face processing. Patients with schizophrenia, however, show attenuated or reversed RH dominance for face processing. It is unclear whether the increased RH dominance found in high schizotypes is specific to face processing or whether it is also observable for other stimuli matched in terms of low-level visual properties. We measured gaze to faces and symmetrical fractal patterns and found higher Magical Ideation (MI) is associated with an increased left-side bias for initial saccade landing points and dwell times when free-viewing faces. These laterality biases were unaffected by facial emotion. Schizotypy scores were not related to laterality biases when viewing fractals. Our results provide further evidence that high schizotypy is associated with an increase in RH dominance for face processing.

Parkinson's disease, typically thought of as a movement disorder, is increasingly recognized as causing cognitive impairment and dementia. Eye movement abnormalities are also described, including impairment of rapid eye movements (saccades) and the fixations interspersed between them. Such movements are under the influence of cortical and subcortical networks commonly targeted by the neurodegeneration seen in Parkinson's disease and, as such, may provide a marker for cognitive decline. This study examined the error rates and visual exploration strategies of subjects with Parkinson's disease, with and without cognitive impairment, whilst performing a battery of visuo-cognitive tasks. Error rates were significantly higher in those Parkinson's disease groups with either mild cognitive impairment (P = 0.001) or dementia (P < 0.001), than in cognitively normal subjects with Parkinson's disease. When compared with cognitively normal subjects with Parkinson's disease, exploration strategy, as measured by a number of eye tracking variables, was least efficient in the dementia group but was also affected in those subjects with Parkinson's disease with mild cognitive impairment. When compared with control subjects and cognitively normal subjects with Parkinson's disease, saccade amplitudes were significantly reduced in the groups with mild cognitive impairment or dementia. Fixation duration was longer in all Parkinson's disease groups compared with healthy control subjects but was longest for cognitively impaired Parkinson's disease groups. The strongest predictor of average fixation duration was disease severity. Analysing only data from the most complex task, with the highest error rates, both cognitive impairment and disease severity contributed to a predictive model for fixation duration [F(2,76) = 12.52, P ≤ 0.001], but medication dose did not (r = 0.18, n = 78, P = 0.098, not significant). This study highlights the potential use of exploration strategy measures as a marker of cognitive decline in Parkinson's disease and reveals the efficiency by which fixations and saccades are deployed in the build-up to a cognitive response, rather than merely focusing on the outcome itself. The prolongation of fixation duration, present to a small but significant degree even in cognitively normal subjects with Parkinson's disease, suggests a disease-specific impact on the networks directing visual exploration, although the study also highlights the multi-factorial nature of changes in exploration and the significant impact of cognitive decline on efficiency of visual search.

Individuals with schizophrenia frequently report disturbances in time perception, but the precise nature of such deficits and their relation to specific symptoms of the disorder is unclear. We sought to determine the relationship between hallucination proneness and time perception in healthy individuals, and whether this relationship is moderated by hypervigilance to threat-related stimuli.206 participants completed the Revised Launay-Slade Hallucination Scale (LSHS-R) and a time reproduction task in which, on each trial, participants viewed a face (happy, angry, neutral, or fearful) for between 1 and 5 s and then reproduced the time period with a spacebar press.High LSHS-R scores were associated with longer time estimates, but only during exposure to angry faces. A factor analysis of LSHS-R scores identified a factor comprising items related to reality monitoring, and this factor was most associated with the longer time estimates.During exposure to potential threat in the environment, duration estimates increase with hallucination proneness. The experience of feeling exposed to threat for longer may serve to maintain a state of hypervigilance which has been shown previously to be associated with positive symptoms of schizophrenia.

INTRODUCTION: According to the cold control theory of hypnosis (Dienes and Perner, 2007), hypnotic response occurs because of inaccurate higher order thoughts of intending. The dorsolateral prefrontal cortex (DLPFC) is a region likely involved in constructing accurate higher order thoughts. Thus, disrupting DLPFC with low frequency repetitive transcranial magnetic stimulation (rTMS) should make it harder to be aware of intending to perform an action. That is, it should be easier to respond to a hypnotic suggestion. METHOD: Twenty-four medium hypnotisable subjects received low frequency rTMS to the left DLPFC and to a control site, the vertex, in counterbalanced order. The hypnotist was blind to which site had been stimulated. Subjects rated how strongly they expected to respond to each suggestion, and gave ratings on a 0-5 scale of the extent to which they experienced the response, for four suggestions (magnetic hands, arm levitation, rigid arm and taste hallucination). The experimenter also rated behavioural response. RESULTS: Low frequency rTMS to the DLPFC rather than vertex increased the degree of combined behavioural and subjective response. Further, subjects did not differ in their expectancy that they would respond in the two conditions, so the rTMS had an effect on hypnotic response above and beyond expectancies. CONCLUSIONS: The results support theories, including cold control theory, postulating a component of hypofrontality in hypnotic response.

Individuals reporting high levels of distractibility in everyday life show impaired performance in standard laboratory tasks measuring selective attention and inhibitory processes. Similarly, increasing cognitive load leads to more errors/distraction in a variety of cognitive tasks. How these two factors interact is currently unclear; highly distractible individuals may be affected more when their cognitive resources are taxed, or load may linearly affect performance for all individuals. We investigated the relationship between self-reported levels of cognitive failuresin daily life and performance in the antisaccade task, a widely used tool examining attentional control. Levels of concurrent cognitive demand were manipulated using a secondary auditory discrimination task. We found that both levels of self-reported cognitive failures and task load increased antisaccade latencies while having no effect on prosaccade eye-movements. However individuals rating themselves as suffering few daily life distractions showed a comparable load cost to those who experience many. These findings suggest that the likelihood of distraction is governed by the addition of both internal susceptibility and the external current load placed on working memory.

It has been suggested that certain types of auditory hallucinations may be the by-product of a perceptual system that has evolved to be oversensitive to threat-related stimuli. People with schizophrenia and high schizotypes experience visual as well as auditory hallucinations, and have deficits in processing facial emotions. We sought to determine the relationship between visual hallucination proneness and the tendency to misattribute threat and non-threat related emotions to neutral faces. Participants completed a questionnaire assessing visual hallucination proneness (the Revised Visual Hallucination Scale – RVHS). High scoring individuals ( N =64) were compared to low scoring individuals ( N =72) on a novel emotion detection task. The high RVHS group made more false positive errors (ascribing emotions to neutral faces) than the low RVHS group, particularly when detecting threat-related emotions. All participants made more false positives when neutral faces were presented to the right visual field than to the left visual field. Our results support continuum models of visual hallucinatory experience in which tolerance for false positives is highest for potentially threatening emotional stimuli and suggest that lateral asymmetries in face processing extend to the misperception of facial emotion.

Research conducted as part of Jess Hall's PhD research, funded by the University of Sussex, supervised by Dr Michael J. Morgan. Previous meta-analyses support a female advantage in decoding non-verbal emotion (Hall, 1978, 1984), yet the mechanisms underlying this advantage are not understood. The present study examined whether the female advantage is related to greater female attention to the eyes. Eye-tracking techniques were used to measure attention to the eyes in 19 males and 20 females during a facial expression recognition task. Women were faster and more accurate in their expression recognition compared with men, and women looked more at the eyes than men. Positive relationships were observed between dwell time and number of fixations to the eyes and both accuracy of facial expression recognition and speed of facial expression recognition. These results support the hypothesis that the female advantage in facial expression recognition is related to greater female attention to the eyes.

Neuregulin 1 (NRG1) has been identified as one of the leading candidate genes for schizophrenia. However, its functional mechanisms and its effects on neurocognition remain unclear. In this study, we used two well-established oculomotor endophenotypes, the antisaccade (AS) and smooth pursuit eye movement (SPEM) tasks, to investigate the functional mechanisms of a single nucleotide polymorphism (SNP) in NRG1 (rs3924999) at the neurocognitive level in a healthy volunteer sample. A total of 114 healthy Caucasian volunteers completed genotyping for NRG1 rs3924999 and infrared oculographic assessment of AS and SPEM (at target velocities of 12°, 24° and 36° per second). Additionally, self-report questionnaires of schizotypy, neuroticism, attention deficit hyperactivity and obsessive-compulsive traits were included. A significant effect of rs3924999 genotype, with gender as a covariate, was found for AS amplitude gain (P < 0.01), with an increasing number of A alleles being associated with increasingly hypermetric performance. No statistically significant associations were found for other AS and SPEM variables or questionnaire scores. These findings indicate that NRG1 rs3924999 affects spatial accuracy on the AS task, suggesting an influence of the gene on the neural mechanisms underlying visuospatial sensorimotor transformations, a mechanism that has been previously found to be impaired in patients with schizophrenia and their relatives. © 2010 Blackwell Publishing Ltd/International Behavioural and Neural Genetics Society.