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Deficits on saccade tasks, particularly antisaccade performance, have been reliably reported in schizophrenia. However, less evidence is available on saccade performance in relation to schizotypy, a personality constellation harboring risk for schizophrenia. Here, we report a large empirical study of the associations of schizotypy and neuroticism with antisaccade and prosaccade performance (Study I). Additionally, we carried out meta‐analyses of the association between schizotypy and antisaccade error rate (Study II). In Study I, N = 526 healthy individuals from the general population aged 18–54 years completed prosaccade and antisaccade tasks as well as the Schizotypal Personality Questionnaire (SPQ). Schizotypy was significantly associated with increased antisaccade error rate, with the disorganized dimension emerging as strongest predictor (β =.118, p =.007). Neuroticism emerged as a significant predictor for prosaccade gain (β =.103, p =.023) and antisaccade latency (β =.101, p =.025). In Study II, random‐effects meta‐analyses were performed on the published data and those from Study I. Meta‐analyses revealed significant associations (all p ≤.003) of antisaccade error rate with positive (g = 0.37), negative (g = 0.26), disorganized (g = 0.36) and overall schizotypy (g = 0.37). Overall, the present work replicates the association between antisaccade direction errors and schizotypy. Significant findings from meta‐analyses provide further evidence of the antisaccade error rate as a putative schizophrenia spectrum marker. There is limited evidence on eye movement performance in relation to schizotypy, necessitating large studies, and meta‐analysis. Here, we show that schizotypy shows small yet significant associations with the direction error rate on the antisaccade task. Neuroticism, a predisposition to experience enhanced negative emotions, was associated with saccadic response speed and spatial accuracy. Significant associations between schizotypy and antisaccade errors were also obtained in meta‐analyses. Overall, we conclude that the antisaccade error rate may be a schizophrenia spectrum indicator. [ABSTRACT FROM AUTHOR]

Previous research has suggested reduced parasympathetic cardiac regulation during cognitive activity in major depressive disorder (MDD). However, little is known about possible abnormalities in sympathetic control and cardiovascular reactivity. This study aimed to provide a comprehensive analysis of autonomic cardiovascular control in the context of executive functions in MDD. Thirty six MDD patients and 39 healthy controls participated. Parameters of sympathetic (pre‐ejection period, PEP) and parasympathetic control (high and low frequency heart rate variability, HF HRV, LF HRV; and baroreflex sensitivity, BRS) as well as RR interval were obtained at rest and during performance of executive function tasks (number‐letter task, n‐back task, continuous performance test, and Stroop task). Patients, as compared to controls, exhibited lower HF HRV and LF HRV during task execution and smaller shortenings in PEP and RR interval between baseline and tasks. They displayed longer reaction times during all conditions of the tasks and more omission errors and false alarms on the continuous performance test. In the total sample, on‐task HF HRV, LF HRV and BRS, and reactivity in HF HRV, LF HRV, and PEP, were positively associated with task performance. As performance reduction arose independent of executive function load of the tasks, the behavioral results reflect impairments in attention and processing speed rather than executive dysfunctions in MDD. Abnormalities in cardiovascular control during cognition in MDD appear to involve both divisions of the autonomic nervous system. Low tonic parasympathetic control and blunted sympathetic reactivity imply reduced physiological adjustment resources and, by extension, provide suboptimal conditions for cognitive performance. This study investigated autonomic cardiovascular control during cognitive activity in MDD. In addition to impaired cognitive performance, patients showed reduced HRV, smaller decreases in pre‐ejection period and RR interval during task execution. On‐task HRV and reactivity in HRV, baroreflex sensitivity, and pre‐ejection period correlated positively with task performance. The study, for the first time, documented that that low tonic parasympathetic control and blunted sympathetic reactivity characterizing MDD may provide suboptimal conditions for cognitive performance. [ABSTRACT FROM AUTHOR]

Saccadic tasks are widely used to study cognitive processes, effects of pharmacological treatments, and mechanisms underlying psychiatric disorders. In genetic studies, it is assumed that saccadic endophenotypes are traits. While internal consistency and temporal stability of saccadic performance is high for most of the measures, the magnitude of underlying trait components has not been estimated, and influences of situational aspects and person by situation interactions have not been investigated. To do so, 68 healthy participants performed prosaccades, antisaccades, and memory-guided saccades on three occasions at weekly intervals at the same time of day. Latent state-trait modeling was applied to estimate the proportions of variance reflecting stable trait components, situational influences, and Person × Situation interaction effects. Mean variables for all saccadic tasks showed high to excellent reliabilities. Intraindividual standard deviations were found to be slightly less reliable. Importantly, an average of 60% of variance of a single measurement was explained by trans-situationally stable person effects, while situation aspects and interactions between person and situation were found to play a negligible role. We conclude that saccadic variables, in standard laboratory settings, represent highly reliable measures that are largely unaffected by situational influences. Extending previous reliability studies, these findings clearly demonstrate the trait-like nature of these measures and support their role as endophenotypes. [ABSTRACT FROM AUTHOR]

Dimensional models of psychosis assume a continuum between schizotypy and schizophrenia. However, little is known about the overlap in brain functional alterations between schizotypy and schizophrenia. Fifty-four healthy volunteers underwent functional magnetic resonance imaging during an antisaccade task, a measure of cognitive control known to be impaired in schizophrenia, and a prosaccade task. Higher positive schizotypy was correlated with higher antisaccade error rates. Associations between reduced blood oxygenation level dependent signal and higher schizotypy were found during antisaccades in the putamen, thalamus, cerebellum, and visual cortex and during prosaccades in the visual cortex, supplementary eye field, and posterior intraparietal sulcus. These findings show that increased schizotypy is associated with decreased antisaccade performance and reduced brain function in regions also affected in schizophrenia, therefore providing evidence of neurocognitive and neurophysiological overlap between schizotypy and schizophrenia. [ABSTRACT FROM AUTHOR]

In addition to symptoms including fatigue, dizziness, reduced drive, or mood disturbance, individuals with chronic low blood pressure (hypotension) frequently report cognitive complaints. While attentional deficits have been empirically confirmed, it is still unknown whether the impairments also encompass executive functions. This study investigated cerebral blood flow modulations in hypotension during a precued antisaccade/prosaccade task requiring the executive function of proactive inhibition in addition to preparatory attention. Using functional transcranial Doppler sonography, bilateral blood flow velocities in the middle cerebral arteries (MCA) were recorded in 39 hypotensive and 40 normotensive participants. In the task, a stimulus appeared left or right of a fixation point 5 s after a cuing stimulus; subjects had to move their gaze to the mirror image position of the stimulus (antisaccade) or toward it (prosaccade control condition). Video‐based eye tracking was used for ocular recording. A right dominant MCA blood flow increase arose during task preparation, which was smaller in hypotensive than normotensive participants. In addition, hypotensive participants exhibited lower peak velocity of the saccadic response. The extent of the reductions in blood flow and task performance in hypotension did not differ between antisaccade and prosaccade conditions. The smaller MCA flow increase may reflect reduced activity in the dorsolateral prefrontal and inferior parietal cortices during proactive inhibition and preparatory attention in hypotension. Given that group differences in blood flow and performance arose independent of task complexity and executive function load, hypotension may be characterized by basic attentional impairments rather than particular executive function deficits. [ABSTRACT FROM AUTHOR]