Contingent Negative Variation and Attention in Schizophrenic and Depressed Patients

Abstract

Contingent negative variation (CNV) is supposed to be a psychophysiological indicator of attention and arousal. Both have been reported to be deteriorated in schizophrenic and depressed patients. Thirty-four patients with major depression, 43 patients with schizophrenia and 49 healthy subjects were investigated during acute illness with a complex three-stimulus go/no-go task which requires different states of attention: trials consisted of three complex figures that were tachistoscopically presented. Three identical figures had to be confirmed by pressing a button (target condition). CNV was measured: (1) after the first figure waiting for the second (baseline condition), (2) after two identical figures waiting for the third (response-relevant condition), (3) after two different figures waiting for the third (response-irrelevant condition). The response-relevant condition compared to baseline significantly intensified CNV in healthy controls and to a minor extent in depressed patients but not in schizophrenics. In the response-relevant conditions in healthy controls, CNV was significantly reduced compared to the response-relevant condition. This clear discrimination between response-relevant and response-irrelevant conditions was not observed in either group of patients. Thus, the applied CNV paradigm was able to discriminate schizophrenic and depressed patients from healthy controls. Furthermore, subtle differences between schizophrenic and depressed patients were detected, reflected by the different CNV development across experimental conditions.

Electrophysiological Endophenotypes for Schizophrenia

“…106,107 While healthy controls generally show a larger component during antisaccades relative to prosaccades, patients fail to show this augmentation and have smaller components in general. 108-110 Deficits in contingent negative variation are not specific to schizophrenia (e.g., depression; 111 ADHD 112 ). More research is needed to understand the reliability of both EEG measures in relation to AS performance, their state-dependence, and impairments in biological relatives.…”

Abnormal proactive and reactive cognitive control during conflict processing in major depression.

“…An earlier study from West, Choi, and Travers (2010) observed that negative affect (measured using a Beck Depression Inventory) in healthy individuals was associated with attenuated proactive and reactive cognitive control (using a counting Stroop task). Moreover in clinically depressed patients, an abnormal contingent negative variation (CNV) during the engagement of preparatory processes has been observed (Ashton, Marshall, Hassanyeh, Marsh, & Wright-Honari, 1994; Heimberg et al, 1999; Giedke & Heimann, 1987). This slow cue-locked cortical potential, which is maximal over frontocentral sites, reflects anticipatory attention and effortful processing (Brunia & van Boxtel, 2001).…”

Circumventing the deficit of context processing in schizophrenia: An event-related brain potential study

“…This would mean that a similar amount of attentional resources has been allocated to the processing of the context prime words. However, against this prediction, it has to be noted that early CNVs generally appear to be smaller in schizophrenia patients than in normals (e.g., Verleger et al, 1999;Heimberg et al, 1999). Nevertheless, in the first study S1 was presented for a relatively brief duration (200 ms), whereas, in the second study, it consisted of previously unknown and complex figures, which were thus difficult to process.…”

“…Thus, no predictions were made as to these components for the chosen protocol. However, it should be noted that the late CNV appears to be of smaller amplitude in patients than in normals (e.g., (Verleger et al, 1999;Heimberg et al, 1999).…”