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Some individuals with schizophrenia report similar feelings of positive affect "in the moment" compared to control participants but report decreased trait positive affect overall. One possible explanation for this disconnection between state and trait positive affect is the extent to which individuals with schizophrenia engage in elaborative processing of positive stimuli. To assess this, we examined evoked gamma band activity in response to positive words over several seconds in a group with schizophrenia, a group with major depressive disorder, and a healthy control group. From a pre-stimulus baseline to 2000 ms after onset of the stimulus (henceforth, "early period"), the schizophrenia group showed a reliable increase in gamma activity compared to both the control and depressed groups, who did not differ from each other. In contrast, the depressed group showed a reliable increase in gamma activity from 2001 to 8000 ms (henceforth, "late period") compared to the other groups, who did not differ from each other. At the same time, the schizophrenia group showed a reliable decrease from the early to late period while the depressed group showed the opposite pattern. In addition, self-reported depression and social anhedonia in the schizophrenia group were related to decreased gamma band activity over the entire processing window. Overall, these results suggest that schizophrenia is associated with increased initial reactivity but decreased sustained elaborative processing over time, which could be related to decreased trait positive affect. The results also highlight the importance of considering depressive symptomology and anhedonia when examining emotional abnormalities in schizophrenia.

This study tests the hypothesis that psychopathy-prone adolescents show reduced anticipatory skin conductance responding. Electrodermal activity was recorded while participants anticipated and responded to a 105dB signaled or unsignaled white-noise burst. Using an extreme groups design, the authors used Child Psychopathy Scale (D. R. Lynam, 1997) scores from a community sample of 335 male adolescents (age 16) to form control (n = 65) and psychopathy-prone (n = 65) groups. Significantly more psychopathy-prone participants were nonresponders in the signaled anticipatory (p = .014), signaled responsivity (p = .037), and unsignaled responsivity (p = .003) conditions compared with controls. Anticipatory hyporesponsivity of psychopathy-prone adolescents similar to the electrodermal hyporesponsivity found in psychopathic adults suggests that this autonomic impairment is present by adolescence and may predispose individuals to adult psychopathy.

Objective: Previous studies report reduced visual event-related potential (ERP) amplitudes in young males at high risk for alcoholism. These findings could involve difficulties at several stages of visual processing. This study was aimed at examining vigilance performance and iconic memory functions in children at high risk or low risk for alcoholism. Method: Sustained vigilance and retrieval from iconic memory were evaluated in 54 (29 male) white children at high risk and 47 (25 male) white children at low risk for developing alcoholism. Children were also grouped according to gender and age (younger: 8-12 years; older: 13-18 years). Results: No differences in visual sensitivity, response criterion or reaction time were associated with risk status on the degraded visual stimulus version of the Continuous Performance Test. For the Span of Apprehension, no differences were found due to risk status when only 1 or 5 distractors were presented, although with 9 distractors a significant effect of risk status was found when it was tested as an interaction with gender and age (decreased accuracy for older high-risk boys compared to older low-risk boys). Conclusions: These findings suggest that ERP deviations are not attributable to stages of visual processing deficits, but represent difficulty involving more complex utilization of information. Implications of these results are that the differences between high- and low-risk children that have been reported previously for visual ERP components (e.g., P300) are not attributable to deficits of attentional or iconic memory mechanisms., Having an alcoholic family member does not appear to significantly affect children's visual attention. Results of a series of computer-generated visual tests were compared for 54 children at high-risk for developing alcoholism and 47 low-risk children. Overall, there were no significant differences in vision, reaction times, or distractibility between the two groups. However, older high-risk boys were more easily distracted than older low-risk boys when tested at maximum distractibility levels., (J. Stud. Alcohol 58: 428-434, 1997) There has been an accumulation of evidence suggesting that aspects of information processing at successive stages of complexity differ among children at high risk [...]

Researchers studied a high risk (HR) group (8 - 18 years old) of 51 children with an average of 4% first - and second-degree relations to an alcoholic and a low-risk group (LR) of 42 children in the same age group who had no first- or second-degree alcoholic relatives or fitted conditions for DSM - III Axis I psychopathology to ascertain if P300 and other ERP (Event Related Potentials) could function as indications of the possibility of developing alcoholism. Amplitudes of the N100 and P200 components and latencies of the components did not influence the risk status.

Prepubertal children who are at high-risk for the development of alcoholism were compared with those who are at low-risk in a visual event-related paradigm. P300 amplitude was reduced in the high-risk boys. The groups did not differ in reaction time data although latency was longer for the hard condition than to the easy one. Moreover, performance accuracy did not differ among the groups. Thus, P300 amplitude is an electrophysiologic marker for high alcoholic risk among prepubertal boys.

A series of tests was conducted to establish the relations between familial alcoholism and a person's cardiovascular responsivity. Groups of nonalcoholic and alcoholic male siblings from families prone to alcoholism were investigated and results were compared with data obtained through experiments using normal brothers from low-risk or control families. It was found that nonalcoholic relatives of alcoholics exhibit higher heart rates while at rest than the low-risk group.

Mechanisms that contribute to perceptual processing dysfunction in schizophrenia were examined by Phillips & Silverstein, and formulated as involving disruptions in both local and higher-level coordination of signals. We agree that dysfunction in the coordination of cognitive functions (disconnection) is also indicated for many of the linguistic processing deficits documented for schizophrenia. We suggest, however, that it may be necessary to add a timing mechanism to the theoretical account.