Token-mediated tool-use by a tufted capuchin monkey (Cebus apella)

This research examined token-mediated tool-use in a tufted capuchin monkey (Cebus apella). We conducted five experiments. In experiment 1 we examined the use of plastic color-coded chips to request food, and in experiments 2–5 we examined the use of color-coded chips to request tools. Our subject learned to use chips to request tools following the same general pattern seen in great apes performing analogous tasks, that is, initial discrimination followed by an understanding of the relationship among tokens, tools, and their functions. Our findings are consistent with the view that parallel representational processes underlie the tool-related behavior of capuchins and great apes. Received: 11 March 1998 / Accepted after revision: 19 August 1998     

Body size estimation in early adolescence: factors associated with perceptual accuracy in a nonclinical sample

This study investigated body size estimation in Norwegian adolescents (aged 12-15; N=406) using a distorting photograph technique. The percentage of over- or underestimation was calculated for pictures of the subject, other persons and a neutral object. The Eating Disorders Inventory for Children (EDI-C) was also completed. Among adolescents at risk of eating problems, girls tended to overestimate their own body size while boys showed a pattern of underestimation, compared to a relatively accurate body perception for low-risk subjects. The groups did not differ in the perception of the neutral object. Important predictors of perceived body size included the size estimation of other children, preoccupation with weight and shape, self-esteem, and emotional instability. The results support the predictive value of body size estimation. Gender differences in judgement bias can be interpreted within present aesthetic ideals and their relation to self perception, body image, and eating problems in adolescence.     

Development and psychometric validation of the verbal affective memory test

We here present the development and validation of the Verbal Affective Memory Test-24 (VAMT-24). First, we ensured face validity by selecting 24 words reliably perceived as positive, negative or neutral, respectively, according to healthy Danish adults’ valence ratings of 210 common and non-taboo words. Second, we studied the test's psychometric properties in healthy adults. Finally, we investigated whether individuals diagnosed with Seasonal Affective Disorder (SAD) differed from healthy controls on seasonal changes in affective recall. Recall rates were internally consistent and reliable and converged satisfactorily with established non-affective verbal tests. Immediate recall (IMR) for positive words exceeded IMR for negative words in the healthy sample. Relatedly, individuals with SAD showed a significantly larger decrease in positive recall from summer to winter than healthy controls. Furthermore, larger seasonal decreases in positive recall significantly predicted larger increases in depressive symptoms. Retest reliability was satisfactory, rs?≥?.77. In conclusion, VAMT-24 is more thoroughly developed and validated than existing verbal affective memory tests and showed satisfactory psychometric properties. VAMT-24 seems especially sensitive to measuring positive verbal recall bias, perhaps due to the application of common, non-taboo words. Based on the psychometric and clinical results, we recommend VAMT-24 for international translations and studies of affective memory.     

Retrieval-induced forgetting and mental imagery

In the present article, we present four experiments in which we examined whether mental imagery can initiate retrieval-induced forgetting. Participants were presented with word pairs (Experiments 1, 2, and 3) or narratives (Experiment 4) and then engaged in selective mental imagery about half of the details from half of the categories. The results indicated that mental imagery can produce the same pattern of impairment as retrieval practice (Experiment 1) and postevent questioning (Experiment 4). Additionally, mental imagery-invoked, retrievalinduced forgetting was found for category cued recall (Experiments 1, 3, and 4) and cued recall (Experiment 2); it was found to dissipate across a 24-h delay, but only when there was no pre-delay test (Experiment 3). Such retrieval-induced forgetting was also found for imagining from the first-person and third-person perspectives (Experiment 4). From these findings, we suggest that the underlying retrieval processes behind mental imagery can initiate retrieval-induced forgetting. The findings are discussed in terms of inhibitory processes.     

Tufted capuchins (<Emphasis Type="Italic">Cebus apella</Emphasis>) attribute value to foods and tools during voluntary exchanges with humans

This research examined exchange and value attribution in tufted capuchin monkeys (Cebus apella). We presented subjects with opportunities to obtain various foods and a tool from an experimenter in exchange for the foods or tool in the subjects' possession. The times elapsed before the first chow biscuits were expelled and/or an exchange took place were recorded as the dependent measures. Laboratory chow biscuits, grapes, apples, and a metal bolt (a tool used to probe for syrup) were used as experimental stimuli. The subjects demonstrated the ability to recognize that exchanges could occur when an experimenter was present with a desirable food. Results indicate that subjects exhibited significant variation in their willingness to barter based upon the types of foods that were both in their possession and presented by the experimenter. Subjects more readily traded chow biscuits for fruit, and more readily traded apples for grapes than grapes for apples. During the exchange of tools and food, the subjects preferred the following in descending order when the probing apparatus was baited with sweet syrup: grapes, metal bolts, and chow biscuits. However when the apparatus was not baited, the values changed to the following in descending order: grapes, chow, and metal bolts. These results indicate that tufted capuchins recognize opportunities to exchange and engage in a simple barter system whereby low-valued foods are readily traded for more highly valued food. Furthermore, these capuchins demonstrate that their value for a tool changes depending upon its utility.     

Generalised Chronic Musculoskeletal Pain as a Rational Reaction to a Life Situation?

While the biomedical model is still theleading paradigm within modern medicine and healthcare, and people with generalised chronicmusculoskeletal pain are frequent users of health careservices, their diagnoses are rated as having thelowest prestige among health care personnel. Anepistemological framework for understanding relationsbetween body, emotions, mind and meaning is presented.An approach based on a phenomenological epistemologyis discussed as a supplement to actions based on thebiomedical model.Within the phenomenological frame of understanding,the body is viewed as a subject and carrier ofmeaning, and therefore chronic pain can be interpretedas a rational reaction to the totality of a person'slife situation. Search for possible hidden individualmeanings in painful muscles presupposes meeting healthpersonnel who view the person within a holistic frameof reference.