title: Altered error processing following vascular thalamic damage: evidence from an antisaccade task.
abstract: Event-related potentials (ERP) research has identified a negative deflection within about 100 to 150 ms after an erroneous response--the error-related negativity (ERN)--as a correlate of awareness-independent error processing. The short latency suggests an internal error monitoring system acting rapidly based on central information such as an efference copy signal. Studies on monkeys and humans have identified the thalamus as an important relay station for efference copy signals of ongoing saccades. The present study investigated error processing on an antisaccade task with ERPs in six patients with focal vascular damage to the thalamus and 28 control subjects. ERN amplitudes were significantly reduced in the patients, with the strongest ERN attenuation being observed in two patients with right mediodorsal and ventrolateral and bilateral ventrolateral damage, respectively. Although the number of errors was significantly higher in the thalamic lesion patients, the degree of ERN attenuation did not correlate with the error rate in the patients. The present data underline the role of the thalamus for the online monitoring of saccadic eye movements, albeit not providing unequivocal evidence in favour of an exclusive role of a particular thalamic site being involved in performance monitoring. By relaying saccade-related efference copy signals, the thalamus appears to enable fast error processing. Furthermore early error processing based on internal information may contribute to error awareness which was reduced in the patients.
authors: Institute of Cognitive Neuroscience, Department of Neuropsychology, Faculty of Psychology, Ruhr University Bochum, Bochum, Germany. jutta.peterburs@ruhr-uni-bochum.de
authors: Jutta
authors: J
authors: Peterburs
authors: Giulio
authors: G
authors: Pergola
authors: Benno
authors: B
authors: Koch
authors: Michael
authors: M
authors: Schwarz
authors: Klaus-Peter
authors: KP
authors: Hoffmann
authors: Irene
authors: I
authors: Daum
authors: Christian
authors: C
authors: Bellebaum
mesh_terms: D000328:Adult; D001364:Awareness / Q000502:physiology*; D001519:Behavior; D016022:Case-Control Studies; D004569:Electroencephalography; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D007361:Intelligence Tests; D008279:Magnetic Resonance Imaging; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology; D008875:Middle Aged; D012438:Saccades / Q000502:physiology*; D013238:Stereotaxic Techniques; D013647:Task Performance and Analysis; D013788:Thalamus / Q000098:blood supply* / Q000473:pathology* / Q000503:physiopathology; D013997:Time Factors