Writer's cramp: A behavioural approach

The history of the treatment of writer's cramp by behaviour therapy is reviewed, and the theoretical assumptions underlying aversive treatment are criticized. The natural history of the disorder is reviewed, including the author's recent research in Student Health Centres. Some special observations are made on the disorder's peculiarities of incidence, both with regard to age of onset and the ethnic or geographical origins of what appears to be a significant minority of patients. Three approaches to studying aetiology are discussed, the neurological, psychopathological and the learning theory of orientations. Some suggestions are offered for further research embracing both experimental psychology and neurological investigation.     

Enduring consequences of experimentally induced biases in interpretation

Previous research has demonstrated that it is possible to induce biases in the interpretation of ambiguous text passages by training. Participants consistently trained to interpret emotionally ambiguous passages in either a negative or positive direction show training-congruent effects when presented with new ambiguous material. These training effects are demonstrated by participants' subsequent recognition ratings for disambiguating sentences, which represent both possible meanings of the novel ambiguous test passages. In this series of experiments, we investigated the durability of these training effects over time spans of up to 1 day and found them to be robust. The findings encourage us to believe that induced biases may serve as a useful analogue to those observed clinically.     

Gender, gender relations, and the social dynamics of children's conversations

The authors investigated the effects of gender on the social dynamics and outcomes of conversations involving 120 children (mean age = 8 years 7 months). Children were taught particular values for different shaped counters and placed in same-gender or mixed-gender pairs with children who were taught different values. Pairs were asked to add the counters together to make a total of 100. Conversations were coded in terms of communication acts and simultaneous speech acts. Boys used more controlling acts overall and more negative interruptions in mixed-gender pairs. Girls used more affiliating acts. All children used more collaborative communication in same-gender pairings. Children whose perspective dominated used more controlling and comparatively fewer affiliating acts. When children reached a compromise, conversations were more collaborative.     

Acculturation attitudes, perceived attitudes of the majority, and adjustment of Israeli-Arab and Jewish-Ethiopian students to an Israeli University

The authors investigated adjustment to an Israeli university by students from two minority groups, Israeli Arabs and Jewish Ethiopians, as a function of their different acculturation attitudes (J. W. Berry, 1990). Social adjustment of both Arabs and Ethiopians was contingent on acculturation attitudes supporting participation with the majority. Psychological adjustment of both groups was negatively associated with personal acculturation preferences that deviated from the shared acculturation attitudes of the respective in-group (i.e., assimilation in the Arab group, and separation in the Ethiopian group). The perceived attitude of the majority also contributed to the psychological adjustment of both groups. Major theoretical implications are that both attitudes of the majority and adjustment to the in-group play an important role in psychological adjustment of immigrants.     

A meta-analytic review of prospective memory and aging

A meta-analysis of prospective memory (PM) studies revealed that in laboratory settings younger participants outperform older participants on tests of both time- and event-based PM (rs=-.39 and -.34, respectively). Event-based PM tasks that impose higher levels of controlled strategic demand are associated with significantly larger age effects than event-based PM tasks that are supported by relatively more automatic processes (rs=-.40 vs. -.14, respectively). However, contrary to the prevailing view in the literature, retrospective memory as measured by free recall is associated with significantly greater age-related decline (r=-.52) than PM, and older participants perform substantially better than their younger counterparts in naturalistic PM studies (rs=.35 and.52 for event- and time-based PM, respectively).     

When learners surpass their models: the acquisition of American Sign Language from inconsistent input

The present study examines the impact of highly inconsistent input on language acquisition. The American deaf community provides a unique opportunity to observe children exposed to nonnative language models as their only linguistic input. This research is a detailed case study of one child acquiring his native language in such circumstances. It asks whether this child is capable of organizing a natural language out of input data that are not representative of certain natural language principles. Simon is a deaf child whose deaf parents both learned American Sign Language (ASL) after age 15. Simon's only ASL input is provided by his late-learner parents. The study examines Simon's performance at age 7 on an ASL morphology task, compared with eight children who have native signing parents, and also compared with Simon's own parents. The results show that Simon's production of ASL substantially surpasses that of his parents. Simon's parents, like other late learners of ASL, perform below adult native signing criteria, with many inconsistencies and errors in their use of ASL morphology. In contrast, Simon's performance is much more regular, and in fact on most ASL morphemes is equal to that of children exposed to a native signing model. The results thus indicate that Simon is capable of acquiring a regular and orderly morphological rule system for which his input provides only highly inconsistent and noisy data. In addition, the results provide some insight into the mechanisms by which such learning may occur. Although the ASL situation is rare, it reveals clues that may contribute to our understanding of the human capacity for language learning.     

Braking reaching movements: a test of the constant tau-dot strategy under different viewing conditions

Following F. Zaal and R. J. Bootsma (1995), the authors studied whether the decelerative phase of a reaching movement could be modeled as a constant tau-dot strategy resulting in a soft collision with the object. Specifically, they investigated whether that strategy is sustained over different viewing conditions. Participants (N = 11) were required to reach for 15- and 50-mm objects at 2 different distances under 3 conditions in which visual availability of the immediate environment and of the reaching hand were varied. Tau-dot estimates and goodness-of-fit were highly similar across the 3 conditions. Only within-participant variability of tau-dot estimates was increased when environmental cues were removed. That finding suggests that the motor system uses a tau-dot strategy involving the intermodal (i.e., visual, proprioceptive, or both) specification of information to regulate the decelerative phase of reaching under restricted viewing conditions. The authors provide recommendations for improving the derivation of tau;(x) estimates and stress the need for further research on how time-to-contact information is used in the regulation of the dynamics of actions such as reaching.     

Priming problem solving with conceptual processing of relevant objects

In the present study, the author explored the effect of processing relevant information on producing solutions to brief insight problems. She hypothesized that the conceptual processing of objects relevant to the target solution would facilitate that solution relative to unrelated objects or the shallow processing of words. The author also explored the effect of knowledge of the relationship between the initial object-processing task and the problem-solving task. The results showed that participants who conceptually processed objects related to the target solution (Experiment 1), but not those who shallowly processed words related to the target solution (Experiment 2), were more likely to produce the solution relative to the control; and knowledge of the relationship between objects and solutions made no difference in the frequency of target solutions produced. The results of Experiment 3 showed that conceptual processing of an object could prime a nondominant solution for an ambiguously worded problem. Taken together, the results of the studies supported the effect of conceptual processing on facilitating insight in problem solving.     

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.     

Neural Recruitment and CognitiveAging: Two Hemispheres Are Better Than One, Especially as You Age

Several neuroimaging studies have reported that older adults show weaker activations in some brain areas together with stronger activations in other areas, compared with younger adults performing the same task. This pattern may reflect neural recruitment that compensates for age-related neural declines. The recruitment hypothesis was tested in a visual laterality study that investigated age differences in the efficiency of bihemispheric processing. Letter-matching tasks of varying complexity were performed under two conditions: (a) matching letters projected to the same visual field (hemisphere) and (b) matching letters projected to opposite visual fields (hemispheres). As predicted by the recruitment hypothesis, older adults generally performed better in the bilateral than unilateral condition, whereas younger adults showed this pattern onlyfor the most complex task. We discuss the relation between these results and neuroimaging evidence for recruitment, and the relevance of the present bihemispheric advantage to other evidence for age-related changes in interhemispheric transfer.