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Jason J. S. Barton – 1st expert on this subject based on the ideXlab platform
The inter-trial effect of prepared but not executed AntisaccadesExperimental Brain Research, 2014Co-Authors: Shanna Yeung, Cristina Rubino, Jaya Viswanathan, Jason J. S. BartonAbstract:
A preceding Antisaccade increases the latency of the saccade in the next trial. Whether this inter-trial effect is generated by the preparation or the execution of the Antisaccade is not certain. Our goal was to examine the inter-trial effects from trials on which subjects prepared an Antisaccade but did not make one. We tested 15 subjects on blocks of randomly ordered prosaccades and Antisaccades. An instructional cue at fixation indicated whether a prosaccade or Antisaccade was required, with the target appearing 2 s later. On 20 % of Antisaccade trials, the target did not appear (prepared-only Antisaccade trials). We analyzed the latencies of all correct prosaccades or Antisaccades preceded by correctly executed trials. The latencies of prosaccade trials were 15 ms shorter if they were preceded by prosaccades than if the prior trial was an Antisaccade. Prosaccades preceded by trials on which Antisaccades were cued but not executed also showed prolonged latencies that were equivalent to those preceded by executed Antisaccades. We conclude that the inter-trial effects from a prior Antisaccade are generated by its preparation rather than its execution. This may reflect persistence of pre-target preparatory activity from the prior trial to affect that of the next trial in structures like the superior colliculus and frontal eye field.
The global effect for AntisaccadesExperimental Brain Research, 2012Co-Authors: Jayalakshmi Viswanathan, Jason J. S. BartonAbstract:
In the global effect, prosaccades are deviated to a position intermediate between two targets or between a distractor and a target, which may reflect spatial averaging in a map encoded by the superior colliculus. Antisaccades differ from prosaccades in that they dissociate the locations of the stimulus and goal and generate weaker collicular activity. We used these Antisaccade properties to determine whether the global effect was generated in stimulus or goal computations, and whether the global effect would be larger for Antisaccades, as predicted by collicular averaging. In the first two experiments, human subjects performed Antisaccades while distractors were placed in the vicinity of either the stimulus or the saccadic goal. Global effects occurred only for goal-related and not for stimulus-related distractors, indicating that this effect emerges from interactions with motor representations. In the last experiment, subjects performed prosaccades and Antisaccades with and without goal-related distractors. When the results were adjusted for differences in response latency, the global effect for rapid responses was three to four times larger for Antisaccades than for prosaccades. Finally, we compared our findings with predictions from collicular models, to quantitatively test the spatial averaging hypothesis: we found that our results were consistent with the predictions of a collicular model. We conclude that the Antisaccade global effect shows properties compatible with spatial averaging in collicular maps and likely originates in layers with neural activity related to goal rather than stimulus representations.
Response selection in prosaccades, Antisaccades, and other volitional saccadesExperimental Brain Research, 2012Co-Authors: Lisa Kloft, Benedikt Reuter, Jayalakshmi Viswanathan, Norbert Kathmann, Jason J. S. BartonAbstract:
Saccades made to the opposite side of a visual stimulus (Antisaccades) and to central cues (simple volitional saccades) both require active response selection but whether the mechanisms of response selection differ between these tasks is unclear. Response selection can be assessed by increasing the number of response alternatives: this leads to increased reaction times when response selection is more demanding. We compared the reaction times of prosaccades, Antisaccades, saccades cued by a central arrow, and saccades cued by a central number, in blocks of either two or six possible responses. In the two-response blocks, reaction times were fastest for prosaccades and Antisaccades, and slowest for arrow-cued and number-cued saccades. Increasing response alternatives from two to six caused a paradoxical reduction in reaction times of prosaccades, had no effect on arrow-cued saccades, and led to a large increase in reaction times of number-cued saccades. For Antisaccade reaction times, the effect of increasing response alternatives was intermediate, greater than that for arrow-cued saccades but less than that for number-cued saccades. We suggest that this pattern of results may reflect two components of saccadic processing: (a) response triggering, which is more rapid with a peripheral stimulus as in the prosaccade and Antisaccade tasks and (b) response selection, which is more demanding for the Antisaccade and number-cued saccade tasks, and more automatic when there is direct stimulus–response mapping as with prosaccades, or over-learned symbols as with arrow-cued saccades.
Ulrich Ettinger – 2nd expert on this subject based on the ideXlab platform
cerebral blood flow responses during prosaccade and Antisaccade preparation in major depressionEuropean Archives of Psychiatry and Clinical Neuroscience, 2019Co-Authors: Alexandra Hoffmann, Ulrich Ettinger, Casandra I Montoro, Gustavo Reyes A Del Paso, Stefan DuschekAbstract:
While impairments in executive functions have been well established in major depressive disorder (MDD), specific deficits in proactive control have scarcely been studied so far. Proactive control refers to cognitive processes during anticipation of a behaviorally relevant event that facilitate readiness to react. In this study, cerebral blood flow responses were investigated in MDD patients during a precued Antisaccade task requiring preparatory attention and proactive inhibition. Using functional transcranial Doppler sonography, blood flow velocities in the middle cerebral arteries of both hemispheres were recorded in 40 MDD patients and 40 healthy controls. In the task, a target appeared left or right of the fixation point 5 s after a cuing stimulus; subjects had to move their gaze to the target (prosaccade) or its mirror image position (Antisaccade). Video-based eye-tracking was applied for ocular recording. A right dominant blood flow increase arose during prosaccade and Antisaccade preparation, which was smaller in MDD patients than controls. Patients exhibited a higher error rate than controls for Antisaccades but not prosaccades. The smaller blood flow response may reflect blunted anticipatory activation of the dorsolateral prefrontal and inferior parietal cortices in MDD. The patients’ increased Antisaccade error rate suggests deficient inhibitory control. The findings support the notion of impairments in proactive control in MDD, which are clinically relevant as they may contribute to the deficits in cognition and behavioral regulation that characterize the disorder.
Antisaccade and prosaccade eye movements in individuals clinically at risk for psychosis comparison with first episode schizophrenia and prediction of conversionEuropean Archives of Psychiatry and Clinical Neuroscience, 2019Co-Authors: Luca Kleineidam, Ingo Frommann, Stephan Ruhrmann, Joachim Klosterkotter, Anke Brockhausdumke, Wolfgang Wolwer, Wolfgang Gaebel, Wolfgang Maier, Michael Wagner, Ulrich EttingerAbstract:
Saccadic eye movements are well-described markers of cerebral function and have been widely studied in schizophrenia spectrum populations. However, less is known about saccades in individuals clinically at risk for schizophrenia. Therefore, we studied individuals in an at-risk mental state (ARMS) (N = 160), patients in their first episode of schizophrenia (N = 32) and healthy controls (N = 75). N = 88 ARMS participants showed an early at-risk mental state (E-ARMS), defined by cognitive-perceptive basic symptoms (COPER) or a combination of risk and loss of function, whereas N = 72 were in a late at-risk mental state (L-ARMS), defined by attenuated psychotic symptoms or brief limited intermittent psychotic symptoms. We examined prosaccades, reflecting overt attentional shifts, and Antisaccades, measuring inhibitory control, as well as their relationship as an indicator of the interplay of bottom–up and top–down influences. L-ARMS but not E-ARMS participants had increased Antisaccade latencies compared to controls. First-episode patients had higher Antisaccade error rates compared to E-ARMS participants and controls, and increased latencies compared to all other groups. Prosaccade latencies did not differ between groups. We observed the expected negative correlation between prosaccade latency and Antisaccade error rate, indicating that individuals with shorter prosaccade latencies made more Antisaccade errors. The magnitude of the association did not differ between groups. No saccadic measure predicted conversion to psychosis within 2 years. These findings confirm the existence of Antisaccade impairments in patients with schizophrenia and provide evidence that volitional response generation in the Antisaccade task may be affected even before onset of clinically overt psychosis.
development of a cued pro and Antisaccade paradigm an indirect measure to explore automatic components of sexual interestArchives of Sexual Behavior, 2017Co-Authors: Verena A Oberlader, Ulrich Ettinger, Rainer Banse, Alexander F SchmidtAbstract:
We developed a cued pro- and Antisaccade paradigm (CPAP) to explore automatic components of sexual interest. Heterosexual participants (n = 32 women, n = 25 men) had to perform fast eye movements toward and away from sexually relevant or irrelevant stimuli across a congruent (i.e., prosaccade toward sexually relevant stimuli, Antisaccade away from sexually irrelevant stimuli) and an incongruent condition (i.e., prosaccade toward sexually irrelevant stimuli, Antisaccade away from sexually relevant stimuli). We hypothesized that pro- and Antisaccade performance would be influenced by the sexual interest-specific relevance of the presented stimulus (i.e., nude female or male stimulus) and the instructed task (i.e., pro- or Antisaccade) and, thus, differ meaningfully between conditions. Results for prosaccades toward sexually relevant stimuli in the congruent condition showed that error rates were lower and latencies were shorter compared with prosaccades toward sexually irrelevant stimuli in the incongruent condition, but only for male participants. In addition, error rates for Antisaccades away from sexually irrelevant stimuli in the congruent condition were lower than for Antisaccades away from sexually relevant stimuli in the incongruent condition, for both female and male participants. Latencies of Antisaccades, however, did not differ between conditions. In comparison with established indirect sexual interest paradigms, the CPAP benefits from measuring highly automated processes less prone to deliberate control. To this end, the CPAP could be applied to explore the interplay of early automatic and deliberate components of sexual information processing.
Dara S. Manoach – 3rd expert on this subject based on the ideXlab platform
Abnormally persistent fMRI activation during Antisaccades in schizophrenia: a neural correlate of perseveration?Schizophrenia Research, 2011Co-Authors: Kara A. Dyckman, Jason J. S. Barton, Yigal Agam, Mark G. Vangel, Donald C. Goff, Dara S. ManoachAbstract:
article Objective: Impaired Antisaccade performance is a consistent cognitive finding in schizophrenia. Antisaccades require both response inhibition and volitional motor programming, functions that are essential to flexible responding. We investigated whether abnormal timing of hemodynamic responses (HDRs) to Antisaccades might contribute to perseveration of ocular motor responses in schizophrenia. We focused on the frontal eye field (FEF), which has been implicated in the persistent effects of Antisaccades on subsequent responses in healthy individuals. Method: Eighteen chronic, medicated schizophrenia outpatients and 15 healthy controls performed Antisaccades and prosaccades during functional MRI. Finite impulse response models provided unbiased estimates of event-related HDRs. We compared groups on the peak amplitude, time-to-peak, and full-width half-max of the HDRs. Results: In patients, HDRs in bilateral FEF were delayed and prolonged but ultimately of similar amplitude to that of controls. These abnormalities were present for Antisaccades, but not prosaccades, and were not seen in a control region. More prolonged HDRs predicted slower responses in trials that followed an Antisaccade. This suggests that persistent FEF activity following an Antisaccade contributes to inter-trial effects on latency. Conclusions: Delayed and prolonged HDRs for Antisaccades in schizophrenia suggest that the functions necessary for successful Antisaccade performance take longer to implement and are more persistent. If abnormally persistent neural responses on cognitively demanding tasks are a more general feature of schizophrenia, they may contribute to response perseveration, a classic behavioral abnormality. These findings also underscore the importance of evaluating the temporal dynamics of neural activity to understand cognitive dysfunction in schizophrenia.
reduced cognitive control of response inhibition by the anterior cingulate cortex in autism spectrum disordersNeuroImage, 2010Co-Authors: Yigal Agam, Jason J. S. Barton, Robert M Joseph, Dara S. ManoachAbstract:
Abstract Response inhibition, or the suppression of prepotent, but contextually inappropriate behaviors, is essential to adaptive, flexible responding. In autism spectrum disorders (ASD), difficulty inhibiting prepotent behaviors may contribute to restricted, repetitive behavior (RRB). Individuals with ASD consistently show deficient response inhibition while performing Antisaccades, which require one to inhibit the prepotent response of looking towards a suddenly appearing stimulus (i.e., a prosaccade), and to substitute a gaze in the opposite direction. Here, we used fMRI to identify the neural correlates of this deficit. We focused on two regions that are critical for saccadic inhibition: the frontal eye field (FEF), the key cortical region for generating volitional saccades, and the dorsal anterior cingulate cortex (dACC), which is thought to exert top–down control on the FEF. We also compared ASD and control groups on the functional connectivity of the dACC and FEF during saccadic performance. In the context of an increased Antisaccade error rate, ASD participants showed decreased functional connectivity of the FEF and dACC and decreased inhibition-related activation (based on the contrast of Antisaccades and prosaccades) in both regions. Decreased dACC activation correlated with a higher error rate in both groups, consistent with a role in top–down control. Within the ASD group, increased FEF activation and dACC/FEF functional connectivity were associated with more severe RRB. These findings demonstrate functional abnormalities in a circuit critical for volitional ocular motor control in ASD that may contribute to deficient response inhibition and to RRB. More generally, our findings suggest reduced cognitive control over behavior by the dACC in ASD.
the relation between Antisaccade errors fixation stability and prosaccade errors in schizophreniaExperimental Brain Research, 2008Co-Authors: Jason J. S. Barton, Donald C. Goff, Manisha Pandita, Katy Thakkar, Dara S. ManoachAbstract:
Whether Antisaccade errors in schizophrenia are due to defects in implementing saccadic inhibition or difficulty in generating novel responses is uncertain. We investigated whether Antisaccade errors were related to difficulty in inhibiting saccades when subjects were asked to maintain steady fixation, a situation that does not require a novel response. We examined the ocular motor data of 15 schizophrenia subjects and 16 healthy subjects. We assessed fixation in two situations: first, during the period before target onset during each saccadic trial, and second, during fixation trials that were interspersed with saccadic trials. We found that schizophrenia subjects had higher rates of fixation losses than control subjects in both situations. Second, both in healthy and schizophrenia subjects, Antisaccade error rate was positively correlated with the frequency of fixation losses in the preparatory period of saccadic trials, but not with the frequency of fixation losses during fixation trials. Third, Antisaccade errors were more likely to occur in trials with unstable fixation than in trials with stable fixation. Last, Antisaccade error rate was also correlated with prosaccade error rate. We conclude that Antisaccade errors are related to difficulties with implementing inhibitory control in the saccadic system. However, the finding of a correlation between the error rates for Antisaccades and prosaccades suggests that this is not specifically concerned with inhibiting the automatic prosaccade, but a more general deficit in implementing goal-oriented behavior.