The impact of performance uncertainty on the postimperative negative variation

Abstract

In a delayed matching-to-sample task, the impact of clear or ambiguous go versus clear no-go signals on the post-imperative negative variation (PINV) was examined in 11 patients with a chronic schizophrenic disorder (DSM-III-R) and in a control group of 13 healthy subjects matched to the patient sample by age, sex, and education. Size and spatial position of a visual S2 had to be matched to one of two visual patterns in the S1 presented 4 s earlier. In 96 trials, the S2 was identical in size with one of the two patterns of S1 (clear matching). These trials varied pseudorandomly, with 60 trials in which the S2 was of intermediate size. On a randomly interspersed additional 48 trials, an S2 differing in color and shape signaled no-go. The electroencephalogram was recorded from Fz, Cz, Pz, F3, F4, C3, C4, P3, and P4. Although groups did not differ in contingent negative variation amplitude, the PINV was generally more pronounced in patients than in controls. In both groups, ambiguity of the to-be-matched S2 produced larger PINV amplitudes; the no-go signal elicited only a small PINV. Differential effects of ambiguity and no-go on PINV amplitude and its scalp distribution suggest that "performance" and "action" uncertainty contribute to PINV generation and that thresholds for both effects are reduced in schizophrenics.

Topography of CNV and PINV in schizotypal personality

“…Furthermore, the augmentation of PINV amplitudes following ambiguous as compared with clear IS was predominant at these frontolateral sites. These results replicate results of previous studies of persons with schizophrenia and healthy control participants using similar Klein, Andresen, et al, 1997;Klein et al, 1996b! or identical Klein et al, 1996a!…”

“…In that task, a frontocentral PINV with a right-sided predominance can reliably be found in healthy individuals~Klein, Andresen, et al, 1997;Klein et al, 1996b!. The rightfrontal maximum can be of similar amplitude in control participants and in patients~Klein, Andresen, et al, 1997!…”

“…onset, whereas the spatiotemporal modulation of the PINV was more "static" and symmetric in schizophrenic patients~Klein, 1997; Klein et al, 1996a!. These studies converge in showing that persons with schizophrenia do not exhibit the right-frontal maximum of the PINV that is seen in healthy participants but show a symmetric distribution or a left-sided predominance. Futhermore, schizophrenic patients maỹ Klein, Andresen, et al, 1997;Klein et al, 1996b! or may not Klein et al, 1996a!…”

“…The PINV in schizophrenic patients has been attributed to "delayed CNV resolution"~Mantanus, Timsith-Berthier, Gerono, & Von Frenckell, 1981;Timsit, Koninckx, Dargent, Fontaine, & Dongier, 1970;Timsit-Berthier, Delaunoy, & Rousseau, 1973!, increased preparation for further stimulus and response evaluation~Birbaum-er, Elbert, Rockstroh, & Lutzenberger, 1986;Rockstroh et al, 1989!, andinability to resolve stimulus ambiguity~Delaunoy, Gerono, &Rousseau, 1978!, or has been termed a prolongated duration CNṼ Timsit-Berthier, Delaunoy, & Gerono, 1978!. Two studies have suggested that high as opposed to low working memory load during the matching of the S2 with the S1 augments the PINV amplitudes only in schizophrenic but not in healthy control individuals; furthermore, the execution of a motor response appears as a critical prerequisite for the rising of the PINV in both populations~Klein, 1997; Klein, Andresen, & Jahn, 1997;Klein, Cohen, Berg, & Rockstroh, 1996b;Werther, 1996!. Current and past etiological conceptions of schizophrenia have assumed the existence of a vulnerability dimension that ranges from healthy to pathological, with schizophrenic disorders representing extreme expressions of the dimensional vulnerability~e.g., Bleuler, 191101988;Kretschmer, 1921, cited in Kendler, 1985Meehl, 1962Meehl, , 1990Raine, Lencz, & Mednick, 1995!. Hence, ab-normalities that are observed in schizophrenic patients and are not a consequence of neuroleptic treatment or long-term hospitalization may be found also in individuals who are assumed to share dispositional factors with schizophrenic patients but who are not psychiatrically ill~Lenzenweger, 1994!.…”

Effects of stressor controllability on psychophysiological, cognitive and behavioural responses in patients with major depression and dysthymia

“…First, the PINV cannot be regarded as a depression-specific cortical index of altered information processing. An enhanced PINV has also been observed in schizophrenic patients where it is similarly regarded as a cortical indicator of task-related ambiguity (Klein et al 1996; Verleger et al 1999). Second, our sample size was probably not large enough to identify higher-order interactions (e.g.…”