Preserved electrophysiological markers of confidence in schizophrenia spectrum disorder

International audienceA large number of behavioral studies suggest that confidence judgments are impaired in schizophrenia, motivating the search for neural correlates of an underlying metacognitive impairment. Electrophysiological studies suggest that a specific evoked response potential reflecting performance monitoring, namely the error-related negativity (ERN), is blunted in schizophrenia compared to healthy controls. However, attention has recently been drawn to a potential confound in the study of metacognition, namely that lower task-performance in schizophrenia compared to healthy controls involves a decreased index of metacognitive performance (where metacognitive performance is construed as the ability to calibrate one’s confidence relative to response correctness), independently of metacognitive abilities among patients. Here, we assessed how this confound might also apply to ERN-blunting in schizophrenia. We used an adaptive staircase procedure to titrate task-performance on a motion discrimination task in which participants (N = 14 patients and 19 controls) had to report their confidence after each trial while we recorded high density EEG. Interestingly, not only metaperceptual abilities were preserved among patients at the behavioral level, but contrary to our hypothesis, we also found no electrophysiological evidence for altered EEG markers of performance monitoring. These results bring additional evidence suggesting an unaltered ability to monitor perceptual performance on a trial by trial basis in schizophreni

Preserved electrophysiological markers of confidence in schizophrenia spectrum disorder

International audienceA large number of behavioral studies suggest that confidence judgments are impaired in schizophrenia, motivating the search for neural correlates of an underlying metacognitive impairment. Electrophysiological studies suggest that a specific evoked response potential reflecting performance monitoring, namely the error-related negativity (ERN), is blunted in schizophrenia compared to healthy controls. However, attention has recently been drawn to a potential confound in the study of metacognition, namely that lower task-performance in schizophrenia compared to healthy controls involves a decreased index of metacognitive performance (where metacognitive performance is construed as the ability to calibrate one’s confidence relative to response correctness), independently of metacognitive abilities among patients. Here, we assessed how this confound might also apply to ERN-blunting in schizophrenia. We used an adaptive staircase procedure to titrate task-performance on a motion discrimination task in which participants (N = 14 patients and 19 controls) had to report their confidence after each trial while we recorded high density EEG. Interestingly, not only metaperceptual abilities were preserved among patients at the behavioral level, but contrary to our hypothesis, we also found no electrophysiological evidence for altered EEG markers of performance monitoring. These results bring additional evidence suggesting an unaltered ability to monitor perceptual performance on a trial by trial basis in schizophreni

A fast intracortical brain–machine interface with patterned optogenetic feedback

International audienceThe development of brain-machine interfaces (BMIs) brings new prospects to patients with a loss of autonomy. By combining online recordings of brain activity with a decoding algorithm, patients can learn to control a robotic arm in order to perform simple actions. However, in contrast to the vast amounts of somatosensory information channeled by limbs to the brain, current BMIs are devoid of touch and force sensors. Patients must therefore rely solely on vision and audition, which are maladapted to the control of a prosthesis. In contrast, in a healthy limb, somatosensory inputs alone can efficiently guide the handling of a fragile object, or ensure a smooth trajectory. We have developed a BMI in the mouse that includes a rich artificial somatosensory-like cortical feedback

Preserved electrophysiological markers of confidence in schizophrenia spectrum disorder

International audienceA large number of behavioral studies suggest that confidence judgments are impaired in schizophrenia, motivating the search for neural correlates of an underlying metacognitive impairment. Electrophysiological studies suggest that a specific evoked response potential reflecting performance monitoring, namely the error-related negativity (ERN), is blunted in schizophrenia compared to healthy controls. However, attention has recently been drawn to a potential confound in the study of metacognition, namely that lower task-performance in schizophrenia compared to healthy controls involves a decreased index of metacognitive performance (where metacognitive performance is construed as the ability to calibrate one’s confidence relative to response correctness), independently of metacognitive abilities among patients. Here, we assessed how this confound might also apply to ERN-blunting in schizophrenia. We used an adaptive staircase procedure to titrate task-performance on a motion discrimination task in which participants (N = 14 patients and 19 controls) had to report their confidence after each trial while we recorded high density EEG. Interestingly, not only metaperceptual abilities were preserved among patients at the behavioral level, but contrary to our hypothesis, we also found no electrophysiological evidence for altered EEG markers of performance monitoring. These results bring additional evidence suggesting an unaltered ability to monitor perceptual performance on a trial by trial basis in schizophreni