Flexible and inflexible response components: a Stroop study with typewritten output

Two experiments were directed at investigating the relationship between response selection and execution in typewriting, and specifically the extent to which concurrent processing takes place. In a Stroop paradigm adapted from [Logan, G. D., & Zbrodoff, N. J. (1998). Stroop-type interference: Congruity effects in colour naming with typewritten responses. Journal of Experimental Psychology: Human Perception and Performance, 24, 978–992], participants typed the names of colour patches with incongruent, congruent, or neutral distractors presented at various stimulus-onset asynchronies. Experiment 1 showed Stroop interference and facilitation for initial keystroke latencies and errors, contrasting with response durations (a measure of response execution) being unaffected by Stroop manipulation. Experiment 2 showed that all three measures were responsive to time pressure; again, Stroop effects were confined to latencies and errors only. The observation that response duration is both flexible under time pressure and protected from response competition, may imply either that response execution is structurally segregated from earlier processing stages, or that encapsulation develops during the acquisition of typing skills.     

Purkinje cell loss by OX7-saporin impairs acquisition and extinction of eyeblink conditioning

The current study examined the effects of globally depleting Purkinje cells in the cerebellar cortex with the immunotoxin OX7-saporin on acquisition and extinction of delay eyeblink conditioning in rats. Rats were given OX7-saporin or saline 2 wk before the start of eyeblink conditioning. The rats that reached a performance criterion of two consecutive days with 80% or greater conditioned responses were given 5 d of extinction training followed by 2 d of reacquisition training. Rats that received infusions of OX7-saporin had 77.2%-97.9% Purkinje cell loss and exhibited impaired acquisition and extinction. The amount of Purkinje cell loss was correlated with the magnitude of the acquisition and extinction impairments. The highest correlations between Purkinje cell number and the rate of acquisition were in lobule HVI and the anterior lobe. The highest negative correlation between Purkinje cell number and the percentage of conditioned responses during extinction was in the anterior lobe. The results indicate that cerebellar Purkinje cells, particularly in the anterior lobe and lobule HVI, play significant roles in acquisition and extinction of eyeblink conditioning.     

Lateralized scratching in chimpanzees (Pan troglodytes): Evidence of a functional asymmetry during arousal

This study evaluated laterality in scratching by chimpanzees (n = 89) during socially arousing circumstances. Hand use and the side of the body scratched was recorded during a baseline and experimental condition. In the experimental condition, chimpanzees were shown a video of other conspecifics sharing, fighting over, and consuming a watermelon. Self-touches were categorized as either rubs or scratches. The chimpanzees showed a significant right hand bias for rubbing and also significantly directed the rubs to the right side of the body. For scratching, the chimpanzees showed no hand preference but a significant bias for scratching on the left side of the body. These results support the view that the right hemisphere regulates the autonomic nervous system during arousal.     

Delusions and decision-making style: use of the Need for Closure Scale

Clinicians and researchers have suggested that rapidity in belief formation, due to having a high 'need for closure' (NFC), may contribute to the acceptance of delusional explanations. The aim of the study is to determine whether NFC has such a direct link with delusions. A secondary aim is to examine if NFC is related to the delusion-associated reasoning process of 'jumping to conclusions'. One hundred and eighty-seven patients with psychosis, recruited for a treatment trial of psychological therapy (the PRP trial), completed the Need for Closure Scale (NFCS), symptom measures, and probabilistic reasoning tasks. The NFCS was considered in terms of its two dimensions: a desire for simple structure and a preference for quick, decisive answers. The individuals with psychosis reported being poor at making quick, decisive answers but required a greater need for simple structure. NFC was associated with levels of anxiety and depression. There were weak links between NFC and both positive and negative symptoms of psychosis, but these were explained by differences in affect. NFCS scores were unrelated to jumping to conclusions. Contrary to the argument that NFC is directly linked to delusions, individuals with delusions actually perceive themselves as indecisive. There was no evidence that NFC-at least as assessed by the NFCS-could be a proximal cause of delusions. Any potential effect on psychotic symptom presentation is indirect, mediated through affect. The use of the NFCS on its own in the study of psychotic symptoms cannot be recommended.     

The Relationship Between Adult Happiness and Self-Appraised Childhood Happiness and Events

The primary purpose of the present research was to relate questionnaire-assessed self-reported childhood happiness and events to adulthood happiness in 387 nonclinical participants. Although childhood happiness and adult happiness were found to be significantly correlated (r = .28, p < .001), there was little relationship between reported adult happiness and reported specific childhood events and circumstances. Childhood events and circumstances, however, were much more highly correlated with childhood happiness (R = .64). Thirty-four percent of the persons who said they were unhappy or very unhappy as a child, but only 9% who said they were happy or very happy as a child, reported that they were unhappy or very unhappy as adults.