Prepulse inhibition (PPI) of event-related potentials (erps) in an auditory discrimination is impaired in normal subjects after amphetamine: Support for a model of schizophrenia

The present research compared the semantic information processing of linguistic stimuli with semantic elaboration of nonlinguistic facial stimuli. To explore brain potentials (ERPs, event-related potentials) related to decoding facial expressions and the effect of semantic valence of the stimulus, we analyzed data for 20 normal subjects ( M age = 23.6 yr., SD = 0.2). Faces with three basic emotional expressions (fear, happiness, and sadness from the 1976 Ekman and Friesen database), with three semantically anomalous expressions (with respect to their emotional content), and the neutral stimuli (face without an emotional content) were presented in a random order. Differences in peak amplitude of ERP were observed later for anomalous expressions compared with congruous expressions. In fact, the results demonstrated that the emotional anomalous faces elicited a higher negative peak at about 360 msec., distributed mainly over the posterior sites. The observed electrophysiological activity may represent specific cognitive processing underlying the comprehension of facial expressions in detection of semantic anomaly. The evidence is in favour of comparability of this negative deflection with the N400 ERP effect elicited by linguistic anomalies.

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Intermodal Compensatory Effects in a Visual Search Task with Congenitally Deaf Adults

Perception ◽

10.1068/v96p0301 ◽

1996 ◽

Vol 25 (1_suppl) ◽

pp. 147-147

Author(s):

P Stivalet ◽

Y Moreno ◽

C Cian ◽

J Richard ◽

P-A Barraud

Keyword(s):

New York ◽

Visual Search ◽

Search Task ◽

Visual Search Task ◽

Event Related Potentials ◽

Normal Subjects ◽

Stimulus Onset ◽

Search Pattern ◽

York Academy ◽

Related Potentials

In a visual search paradigm we measured the stimulus onset asynchrony (SOA) between a stimulus and a mask that was required to reach 90% correct responses. This procedure has the advantage of taking into account the real processing time and excluding the time for the generation of the motor response. Twelve congenitally deaf adult subjects and twelve normal subjects were given a visual search task for a target letter O among a varying number of distractor letters Q and vice-versa. In both groups we found the asymmetrical visual search pattern classically observed with parallel processing for the search for the target Q and with serial processing for the search for the target O (Treisman, 1985 Computer Vision, Graphics, and Image Processing31 156 – 177). The difference between the mean search slopes for an O target was not statistically significant between the groups; this might be due to the variability within the groups. The visual search amidst the congenitally deaf does not seem to benefit from a compensatory effect in relation to the acoustic deprivation. Our results seem to confirm data reported by Neville (1990 Annals of the New York Academy of Science 71 – 91) obtained by an electrophysiological technique based on event-related potentials. Nevertheless, the deaf subjects were 2.5 times faster at the visual search task.

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Brain Indicators of Altered Attention and Information Processing in Schizophrenic Patients

The British Journal of Psychiatry ◽

10.1192/bjp.148.4.414 ◽

1986 ◽

Vol 148 (4) ◽

pp. 414-420 ◽

Cited By ~ 46

Author(s):

K. Barrett ◽

W. C. McCallum ◽

P. V. Pocock

Keyword(s):

Information Processing ◽

Event Related Potentials ◽

Normal Subjects ◽

Detection Task ◽

Auditory Target ◽

Positive Potential ◽

Stimulus Evaluation ◽

Schizophrenic Patients ◽

Related Potentials ◽

Target Detection Task

Late components of brain event-related potentials reflect aspects of selective attention, stimulus evaluation, and possibly memory update mechanisms. Several of these components were measured during an auditory target detection task, performed by 20 schizophrenic and 20 normal subjects. Both the amplitude of those components and a more general late amplitude measure were significantly reduced in schizophrenics, for both target and non-target stimuli. One general late amplitude measure, from the scalp vertex, could alone correctly classify 85% of patients and 95% of controls. The source of these differences may lie in a protracted positive potential shift.

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Differential Effects of Acute Alcohol on Prepulse Inhibition and Event-Related Potentials in Adolescent and Adult Wistar Rats

Alcoholism Clinical and Experimental Research ◽

10.1111/j.1530-0277.2008.00794.x ◽

2008 ◽

Vol 32 (12) ◽

pp. 2062-2073 ◽

Cited By ~ 15

Author(s):

Jerry P. Pian ◽

Jose R. Criado ◽

Cindy L. Ehlers

Keyword(s):

Prepulse Inhibition ◽

Wistar Rats ◽

Event Related Potentials ◽

Differential Effects ◽

Related Potentials

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Latency variability and temporal interrelationships of the auditory event-related potentials (N1, P2, N2, and P3) in normal subjects

Electroencephalography and Clinical Neurophysiology/Evoked Potentials Section ◽

10.1016/0168-5597(86)90037-7 ◽

1986 ◽

Vol 65 (1) ◽

pp. 59-71 ◽

Cited By ~ 76

Author(s):

H.J Michalewski ◽

D.K Prasher ◽

A Starr

Keyword(s):

Event Related Potentials ◽

Normal Subjects ◽

Auditory Event ◽

Latency Variability ◽

Related Potentials ◽

Auditory Event Related Potentials

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Event-Related Potentials in a Decision-Making Task with Delayed and Immediate Reward Conditions

Journal of Psychophysiology ◽

10.1027/0269-8803.19.4.270 ◽

2005 ◽

Vol 19 (4) ◽

pp. 270-274 ◽

Cited By ~ 4

Author(s):

Marcus Heldmann ◽

Jascha Rüsseler ◽

Thomas F. Münte

Keyword(s):

Decision Making ◽

Performance Monitoring ◽

Event Related Potentials ◽

Normal Subjects ◽

Delay Of Gratification ◽

Brain Potentials ◽

Delayed Reward ◽

Related Potentials

Abstract: We investigated performance monitoring of a group of healthy normal subjects in a delay of gratification paradigm. Focusing on response-locked event-related brain potentials we observed an Ne-Pe-like complex in all conditions. While there was no modulation of the Ne-like component, the subsequent Pe-like positivity was largest in conditions in which subjects went for the largest immediate reward, regardless of whether this was disadvantageous (i.e., foreclosed a larger delayed reward) or not. We interpreted the positivity as mainly reflecting the size of the immediate reward.

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