Are there interactions among dysfunctional beliefs in obsessive compulsive disorder?

Contemporary cognitive models of obsessive-compulsive disorder emphasize the importance of various types of dysfunctional beliefs, such as beliefs about inflated responsibility, perfectionism and the importance of controlling one's thoughts. These beliefs have been conceptualized as main effects, each influencing obsessive-compulsive symptoms independent of the contributions of other beliefs. It is not known whether beliefs interact with one another in their influence on obsessive-compulsive symptoms. To investigate this issue, data from 248 obsessive-compulsive disorder patients were analyzed. Dependent variables were the factor scores on the 4 Padua Inventory subscales. Predictor variables were the factor scores from the 3 factors (inflated responsibility, perfectionism and controlling one's thoughts) of the Obsessive Beliefs Questionnaire and their 2- and 3-way interactions. Regression analyses revealed significant main effects; in almost all analyses one or more of inflated responsibility, perfectionism, and controlling one's thoughts factors predicted scores on the Padua factors even after controlling for general distress. There was no evidence that beliefs interact in their effects on obsessive-compulsive symptoms, thereby providing a relatively unusual instance in which a simpler explanation (main effects only) is just as powerful as a more complex model.     

Extinction-induced immobility in the water maze and its neurochemical concomitants in aged and adult rats: a possible model for depression?

Extinction of escape behavior in the water maze due to the removal of the platform, was hypothesized to induce a negative state, including the development of immobility, which is held to reflect a state of "despair" when measured in the forced swimming test. 27 aged and 8 adult animals (26 and 3 months old Wistar rats, respectively) were tested in the water maze during nine days with a platform hidden, followed by 7 days of extinction trials with the platform absent. As expected, both age groups developed immobility over the extinction trials, with the aged showing more than the adults. To examine whether the age difference in immobility was related to performance differences during acquisition, the aged were subdivided into superior, intermediate and inferior learners (n = 9 per group) on the basis of overall times to platform during acquisition, and compared with each other and the adults. Results showed that the aged inferior learners displayed the highest levels of immobility among the aged. Immobility scores were then correlated with post-mortem neurotransmitter contents in the hippocampus and ventral striatum. In the ventral striatum, levels of immobility were correlated with levels of acetylcholine, dopamine and the metabolite dihydroxyphenylacetic acid in the aged, and with norepinephrine in the adults. The data support the hypothesis that multiple extinction trials in the water maze result in immobility that may indicate "behavioral despair," and that striatal neurotransmitter systems correlate with the degree of its expression. The concept of extinction-induced despair is held to provide the promise of a conceptual and empirical model of human depression that is the consequence of loss of reinforcers.     

The effect of manipulated sympathy and anger on left and right frontal cortical activity

The present research extended past research demonstrating that approach-motivated anger is associated with greater left than right frontal cortical activity. Because past research had examined difference scores between left and right frontal activity, it was unable to test whether approach-motivated anger increased left activity, decreased right activity, or both. In addition, the present research examined a potential moderator of the effect of insult on left frontal activity. That is, it tested whether sympathy for an insulting person would reduce the left frontal activity that occurs following being insulted. Results indicated that left frontal activity was increased and right frontal activity was decreased by the insult. Moreover, these effects were inhibited when high levels of sympathy were first aroused.     

The associative memory deficit of older adults: further support using face-name associations

Previous studies have established an associative deficit hypothesis (Naveh-Benjamin, 2000), which attributes part of older adults' deficient episodic memory performance to their difficulty in creating cohesive episodes. In this article, the authors further evaluate this hypothesis, using ecologically relevant materials. Young and old participants studied name-face pairs and were then tested on their recognition memory for the names, faces, and the name-face pairs. The results extend the conditions under which older adults exhibit an associative deficit. They also show that reduced attentional resources are not the sole mediator of this deficit.     

Partition-edit-count: naive extensional reasoning in judgment of conditional probability

The authors provide evidence that people typically evaluate conditional probabilities by subjectively partitioning the sample space into n interchangeable events, editing out events that can be eliminated on the basis of conditioning information, counting remaining events, then reporting probabilities as a ratio of the number of focal to total events. Participants' responses to conditional probability problems were influenced by irrelevant information (Study 1), small variations in problem wording (Study 2), and grouping of events (Study 3), as predicted by the partition-edit-count model. Informal protocol analysis also supports the authors' interpretation. A 4th study extends this account from situations where events are treated as interchangeable (chance and ignorance) to situations where participants have information they can use to distinguish among events (uncertainty).     

Size of the neocerebellar vermis is associated with cognition in healthy elderly men

Cerebellar volumes show small positive correlations with cognitive ability in young adults, but no studies have examined this relationship in older adults. Furthermore, no studies have examined relationships between sizes of subareas of the cerebellum and cognitive ability. We hypothesized that size of the two areas of the neocerebellar vermis would correlate with a battery of eight cognitive tests in 50 men aged 65-70. Size of the neocerebellar areas of the vermis correlated positively with several cognitive tests (r's=.29-.37, p<.05), whilst sizes of other parts of the vermis did not correlate with any cognitive tests. Total cerebellar volumes correlated significantly with a test of nonverbal reasoning (r=.030, p=.42). These findings suggest a specific association of neocerebellar vermis size with variations in cognitive ability in older adults.     

A new breed of computer users: Rats control a cursor via joystick manipulation

Many exciting findings have been reported in the 15 years since monkeys were first demonstrated to have the capacity to perform computerized tasks. The present data indicate that albino rats can also learn to respond to computer-generated stimuli by manipulating a joystick. Although the rat’s control of the cursor is not as skillful as has been reported for primate species, it is clearly better than chance and suggests the great potential for comparative investigation afforded by use of the computer test system.