On boredom and experimentation in humans

This article discusses the ethical and methodological issues associated with boredom experienced by human participants during psychological experiments. Ways are suggested in which informed consent, briefing, and debriefing can be used to prevent or remedy boredom induced during experiments. We address methodological and ethical concerns, and we discuss the advantages of the proposed approach for experimenters' practice and training of undergraduate students. Future directions for much needed research on these topics are also emphasized.     

Win-shift and win-stay learning in the short-beaked echidna (<Emphasis Type="Italic">Tachyglossus aculeatus</Emphasis>)

Numerous previous investigators have explained species differences in spatial memory performance in terms of differences in foraging ecology. In three experiments we attempted to extend these findings by examining the extent to which the spatial memory performance of echidnas (or "spiny anteaters") can be understood in terms of the spatio-temporal distribution of their prey (ants and termites). This is a species and a foraging situation that have not been examined in this way before. Echidnas were better able to learn to avoid a previously rewarding location (to "win-shift") than to learn to return to a previously rewarding location (to "win-stay"), at short retention intervals, but were unable to learn either of these strategies at retention intervals of 90 min. The short retention interval results support the ecological hypothesis, but the long retention interval results do not. Electronic Publication     

The effects of adult aging and induced positive and negative mood on planning

Changes in executive functions have been found in older adults and also in young adults experiencing positive or negative mood states. The current study investigated the hypothesis that older adults would show greater executive function impairment following mood induction than young adults. Ninety-six participants (half aged 19-37, half aged 53-80) completed a neutral, positive, or negative mood induction procedure, followed by the Tower of London planning task. Significant interactions were found between age and mood such that older adults showed greater planning impairment than young adults in both the positive and negative mood conditions. Emotionally salient events occurring before testing may interfere with executive function in older adults.     

Intergroup emotions: explaining offensive action tendencies in an intergroup context

Three studies tested the idea that when social identity is salient, group-based appraisals elicit specific emotions and action tendencies toward out-groups. Participants' group memberships were made salient and the collective support apparently enjoyed by the in-group was measured or manipulated. The authors then measured anger and fear (Studies 1 and 2) and anger and contempt (Study 3), as well as the desire to move against or away from the out-group. Intergroup anger was distinct from intergroup fear, and the inclination to act against the out-group was distinct from the tendency to move away from it. Participants who perceived the in-group as strong were more likely to experience anger toward the out-group and to desire to take action against it. The effects of perceived in-group strength on offensive action tendencies were mediated by anger.     

Hypermnesia: Age-related differences between young and older adults

Hypermnesia is a net improvement in memory performance that occurs across tests in a multitest paradigm with only one study session. Our goal was to identify possible age-related differences in hypermnesic recall. We observed hypermnesia for young adults using verbal (Experiment 1) as well as pictorial (Experiment 2) material, but no hypermnesia for older adults in either experiment. We found no age-related difference in reminiscence (Experiments 1 and 2), though there was a substantial difference in intertest forgetting (Experiments 1 and 2). Older, relative to young, adults produced more forgetting, most of which occurred between Tests 1 and 2 (Experiments 1 and 2). Furthermore, older, relative to young, adults produced more intrusions. We failed to identify a relationship between intrusions and intertest forgetting. We suggest that the age-related difference in intertest forgetting may be due to less efficient reinstatement of cues at test by older adults. The present findings reveal that intertest forgetting plays a critical role in hypermnesic recall, particularly for older adults.     

The influence of distinctive processing on retrieval-induced forgetting

Recall of a portion of a previously experienced list benefits subsequent recall of that portion of the list but leads to poorer recall of nonpracticed items from the same set (Anderson, Bjork, & Bjork, 1994). One explanation for this retrieval-induced forgetting is that during practice of part of a set, the non-practiced items compete for recall and are suppressed; this suppression process inhibits later recall of the nonpracticed items. Two experiments were conducted to investigate the relationship between distinctive processing of the original set and retrieval-induced forgetting, on the assumption that distinctive processing reduces response competition. In the first experiment, distinctive processing induced by difference judgments among the studied items did reduce forgetting relative to a standard encoding task and a similarity judgment task. In fact, the difference judgment task completely eliminated retrieval-induced forgetting. In the second experiment, the similarity judgment task was analyzed in relation to a task assumed to foster associative integration (Anderson & McCulloch, 1999). Even though the similarity judgment met the requirements for associative integration, retrieval-induced forgetting persisted following similarity judgment. The results are consistent with the view that distinctive processing benefits memory within an organizational context (Hunt & McDaniel, 1993; Smith & Hunt, in press).     

Attention and luminance detection: effects of cues, masks, and pedestals

Three experiments investigated the effects of attention on the detection of luminance targets in a spatial-cuing paradigm. Gabor patch stimuli of 30, 60, or 90 ms duration, equated for detectability, were presented (a) against a uniform field with a checkerboard backward mask, (b) atop a 15% luminance pedestal with a backward mask, or (c) atop a luminance pedestal with no backward mask. Signal detection analysis showed that detection sensitivity was significantly enhanced at attended locations for all observers when backward masks were used, both when targets were presented against a uniform field and when a pedestal was used. However, when no masks were used there was no cuing advantage of any kind. The results show that the cuing effect in simple detection depends on the use of backward masks, a finding that resolves the inconsistencies previously associated with studies of this type.     

Modality effects and the development of the word length effect in children

Two experiments investigated the development of the word length effect in children aged 4 to 10 years, comparing auditory and visual stimuli. The question addressed was whether word length effects emerged earlier with auditory presentation or visual presentation, or whether they emerged at the same age regardless of presentation modality. Results provided evidence that word length effects emerge earlier with visual than auditory presentation. The implication of our results is that with visual presentation, 4-year-olds engage in some form of verbalization strategy that involves obtaining phonological representations of picture names and mapping them on to articulatory output plans. This strategy is clearly verbal in nature, but is not necessarily characterised as cumulative verbal rehearsal.     

The Factor Structure of the Beavers Interactional Scales

Confirmatory factor analysis and regression analyses of the Beavers Interactional Scales did not appear to support the model offered by its developers, namely, several specified family attributes contributing respectively to two global factors of Family Competence and Family Style. Moreover, regression analysis indicated that only three of 12 items predicted raters' assessments of Global Family Health, and one of seven items predicted Global Family Style. Individuals interested in the family dynamic centripetal/centrifugal might best think of that as a unitary entity and rate it accordingly.