Gender, Somatization, and Psychopathic Traits in a College Sample

The structure of psychopathic traits and their association with somatization symptoms were investigated in a sample of 199 undergraduate college students enrolled in introductory psychology classes. Using multiple measures of psychopathic traits, an iterated principal axis (IPA) analysis revealed two dimensions of psychopathy that were similar to ones typically found in forensic samples. One dimension focused on a cold, callous, and unemotional interpersonal style and the second dimension focused on an impulsive and antisocial lifestyle. These two dimensions emerged for both men and women, although the correlation between the two was somewhat higher for men than women. Also, the callous and unemotional dimension was negatively correlated with somatization symptoms, and the impulsive and antisocial dimension was positively associated with somatization symptoms. This pattern of associations was similar for both men and women and it suggests that somatization symptoms may be one aspect of the high rate of negative affectivity experienced by antisocial individuals.     

Dilution, not load, affects distractor processing

Lavie and Tsal (1994) proposed that spare attentional capacity is allocated involuntarily to the processing of irrelevant stimuli, thereby enabling interference. Under this view, when task demands increase, spare capacity should decrease and distractor interference should decrease. In support, Lavie and Cox (1997) found that increasing perceptual load by increasing search set size decreased interference from an irrelevant distractor. In three experiments, we manipulated the cue set size (number of cued locations) independently of the display set size (number of letters presented). Increasing the display set size reduced distractor interference regardless of whether the additional letters were relevant to the task. In contrast, increasing the cue set size increased distractor interference. Both findings are inconsistent with the load explanation, but are consistent with a proposed two-stage dilution account.     

Maze learning in Alzheimer's disease

Alzheimer's disease (AD) patients and normal elderly controls performed a block of 10 trials on a finger maze, followed by a 45-min period during which verbal learning measures were administered. Subjects then performed an additional 10 trials on the original maze, followed by 10 trials on a new maze. The AD patients and a subset of control subjects decreased mean completion time across Blocks 1 and 2, suggesting skill acquisition. Mean time on Block 3 was significantly less than mean time on Block 1, suggesting skill generalization. A subset of controls did not show the above pattern. The results of this study suggest that AD patients are able to acquire and generalize a cognitively mediated perceptual-motor skill.     

Hypertension risk and caffeine's effect on cardiovascular activity during mental stress in young men

Examined the cardiovascular effects of caffeine plus behavioral stress in men low versus high in risk of essential hypertension. Caffeine (3.3 mg/kg, equivalent to 2 to 3 cups of coffee) or placebo was given on alternate days to 19 low-risk men (negative for parental hypertension and low-normal resting blood pressure, BP) and 20 high-risk men (positive history, high-normal BP). Forty minutes later, each worked for 15 min on a demanding psychomotor task during which BP, cardiac output, and vascular resistance were determined. During rest, caffeine raised vascular resistance in both groups. During the task, it supra-additively increased the systolic BP response by enhancing the rise in cardiac output, producing equivalent BP rises in both groups. Due to the higher resting pressures of the high-risk men, caffeine plus the task resulted in 50% of these having transient BP of 140/90 mg Hg or greater. Caffeine in combination with mental stress may produce undesirable BP in those at risk for hypertension.     

Developmental changes in the recognition and comprehension of facial expression: implications for frontal lobe function.

Children aged 6-15 years old and adults (over 18) were given three tests designed to test perception and comprehension of facial expression. In the first test subjects were given two composite symmetrical faces made from the left or right half of a normal face, the subjects' task being to indicate which composite more closely resembled the original face. In the second test the subjects matched a series of photographs from Life magazine with key photographs of one of six distinct emotions (sad, fear, happy, anger, disgust, surprise). In the third test the subjects chose a key photograph that was appropriate for the face of a faceless character in a cartoon. On the composite faces test the subjects in all groups exhibited a preference for the left visual field composite, implying that all age groups were processing the faces in a similar manner. The results of the other two tests showed that there was an improvement in the perception of facial expression between the ages of 6 and 8 years, little change until about 13 years, and then a second improvement to adult performance at about 14 years. The performance of the 8- to 13-year-old children was similar to that of adult patients with frontal lobe injuries, which could be taken as evidence that the regions of the frontal lobe involved in the performance of these tasks may not be mature until about 14 years of age.     

The Relation of Lifetime Cognitive Activity and Lifetime Access to Resources to Late-life Cognitive Function in Older African Americans

ABSTRACT

Research in older Caucasians has demonstrated that cognitive activity is related to cognitive function in late adulthood. Knowledge of this association is limited in older minority populations. We examined the relation of cognitive activity and access to cognitive resources, with cognitive function in a group of 108 older African Americans. We constructed two scales to measure the frequency of cognitive activity and the presence of resources that promote cognitive activity during early and late life. Both measures had high internal consistency and the cognitive activity scale had adequate temporal stability over a 4-week interval. In analyses that controlled for age and education, more frequent lifetime cognitive activity was related to current cognitive function, but lifetime cognitive resources only approached significance. The results suggest that both measures are psychometrically sound in a minority population and that lifetime cognitive activity may contribute to current cognitive function in African Americans.     

Synchrony effects in automatic and controlled retrieval

Using a speeded retrieval procedure, we investigated time-of-day effects in automatic and controlled retrieval. Morning-type adults were tested at either peak (early morning) or off-peak (late afternoon) times on a speeded implicit (Experiment 1) or explicit (Experiment 2) stem completion task. In Experiment 1, retrieval strategies were identified by changes in response speed between a practice phase with rapid retrieval and an implicit memory test phase. Performance based on controlled retrieval (shown by slowdown participants) showed more priming at peak than at off-peak times of day, a finding confirmed in Experiment 2, in which the participants were given intentional retrieval instructions when the materials switched. In contrast, performance based on automatic retrieval (shown by nonslowdown participants) did not differ across peak and off-peak times. The finding suggests a robust synchrony effect in controlled retrieval, but not in automatic retrieval, which does not appear to vary across the day.