Previous mindfulness experience interacts with brief mindfulness induction when reducing stimulus overselectivity

The current study examined the effects of a brief mindfulness induction on overselectivity. Participants were randomly assigned to a mindfulness, unfocused attention (relaxation), or no‐intervention group. Participants experienced their designated intervention for 10 min, and they underwent simultaneous discrimination training (AB+ CD?) followed by an extinction test (AvC, AvD, BvC, and BvD). Levels of mindfulness were measured by the Toronto Mindfulness Scale, and participants were asked about their previous experience with mediation and mindfulness practice. Mindfulness reduced overselectivity, and previous levels of mindfulness experience identified by a single question moderated this effect, with mindful‐experienced participants showing less overselectivity. Both findings have some practical utility in the ongoing investigation of the possible use of mindfulness in medical settings.     

Prevalence of pathological Internet use among university students and correlations with self-esteem, the General Health Questionnaire (GHQ), and disinhibition.

Over the last few years, there has been increased interest in the addictive potential of the Internet. The current study was an attempt to replicate common findings in the literature and provide more evidence for the existence of Internet addiction among students--a population considered to be especially vulnerable. A total of 371 British students responded to the questionnaire, which included the Pathological Internet Use (PIU) scale, the General Health Questionnaire (GHQ-12), a self-esteem scale, and two measures of disinhibition. Results showed that 18.3% of the sample were considered to be pathological Internet users, whose excessive use of the Internet was causing academic, social, and interpersonal problems. Other results showed that pathological Internet users had lower self-esteem and were more socially disinhibited. However, there was no significant difference in GHQ scores. These results are discussed in relation to the methodological shortcomings of research in the area as a whole.     

Resurgence of response sequences during extinction in rats shows a primacy effect

Rats were trained to emit a series of three-response sequences to a criterion (i.e., more than 80% of all emitted sequences correct over five successive sessions). Each rat was trained on a series of different, three-response sequences. After the final three-response sequence was acquired, two extinction tests were administered, and the three-response sequences that re-emerged during these extinction tests were noted. Resurgence effects during extinction were observed; that is, the previously trained sequences were emitted. These resurgence effects followed an orderly pattern, which involved a primacy effect. The rats initially emitted the immediately previously trained response, but then started to emit the response sequence they first were trained to emit. Thus, resurgence behavior during extinction can be an orderly function of previous training history. These results replicate those previously obtained with human subjects.     

The effect of signaled reinforcement on rats' fixed-interval responding

Four experiments examined the effect on rats' response rate of presenting a brief (500 ms) stimulus simultaneously with the delivery of food on fixed-interval (FI) schedules. In Experiment 1, reinforcement signals that were spatially diffuse (both tones and lights) elevated rates of responding, but responding was attenuated by localized visual stimuli. The remaining experiments examined the signal-induced potentiation of responding. In Experiment 2, a tone reinforcement signal potentiated response rates on an FI schedule, but attenuated response rates on a variable-interval (VI) schedule. This difference was obtained even though the overall rate of responding was equated on the two schedules before the introduction of the signal. Signal-induced potentiation of responding occurred over a range of FI values employed in Experiment 3. In Experiment 4, presenting a reinforcement signal when high local rates of response had occurred immediately before reinforcement resulted in potentiated rates of responding on an FI schedule. The opposite effect on response rate occurred when the reinforcement signal followed only low local rates of response. These results indicate that a variety of factors influence the effects of a reinforcement signal. They imply, however, that the local rate of response at the time of reinforcement is a key factor in establishing the nature of the signaling effect.     

Speech perception in rats: use of duration and rise time cues in labeling of affricate/fricative sounds

The voiceless affricate/fricative contrast has played an important role in developing auditory theories of speech perception. This type of theory draws some of its support from experimental data on animals. However, nothing is known about differential responding of affricate/fricative continua by animals. In the current study, the ability of hooded rats to "label" an affricate/fricative continuum was tested. Transfer (without retraining) to analogous nonspeech continua was also tested. The nonspeech continua were chosen so that if transfer occurred, it would indicate whether the animals had learned to use rise time or duration cues to differentiate affricates from fricatives. The data from 9 of 10 rats indicated that rats can discriminate between these cues and do so in a similar manner to human subjects. The data from 9 of 10 rats also demonstrated that the rise time of the stimulus was the basis of the discrimination; the remaining rat appeared to use duration.     

Cognitive correlates of depressive symptoms in 11-year-old children

Self-reports of depressive symptoms were obtained for 792 11-year-old New Zealand children using a structured interview. The aim of the present study was to test the hypothesis that depressive symptomatology in children is associated with impairment on cognitive tasks. The results did not support this hypothesis. Depression was unrelated to performance on various subscales of the WISCR, whereas self-reported inattention was associated with poor performance. Depressive symptoms, however, were significantly related to lower self-esteem and a poorer self-perception of scholastic ability.The Dunedin Multidisciplinary Health and Development Research Unit is supported by the Medical Research Council of New Zealand and the Departments of Education and Health, and involves several departments of the University of Otago. Much of the data are gathered by voluntary workers from the Dunedin community. The authors are indebted to the many people whose contributions make this ongoing study possible.     

Signaled Delay of Reinforcement: Effects of Postconditioning Manipulation of Context Associative Strength on Instrumental Performance

Two experiments examined the influence of postconditioning treatments of contextual cues on instrumental responding acquired with a signaled delay of reinforcement schedule. In Experiment 1, mere exposure to the conditioning context after instrumental training resulted in an attenuated response rate during an extinction test. In the second experiment, responding was decreased by exposure to the contextual cues or sessions in which signaled noncontingent reinforcements occurred. The greatest response decrement, however, occurred following unsignaled noncontingent food presentations. The results are discussed with respect to the different roles of contextual cues on operant responding.     

Sex and birth order differences in filial behavior

Personal interviews were conducted with 499 children of elderly white widows. Results showed no birth order differences in the provision of assistance to the elderly; however, there were significant sex differences. Daughters performed more caretaking activities and social services and provided more emotional support for their mothers than did sons. Sons had a tendency, though insignificant, to provide more advisory assistance to their mothers. After adjusting for situational differences between daughters and sons a sex difference remained only for the provision of emotional support.