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.     

Hippocampal damage and exploratory preferences in rats: memory for objects, places, and contexts

Rats have a natural tendency to spend more time exploring novel objects than familiar objects, and this preference can be used as an index of object recognition. Rats also show an exploratory preference for objects in locations where they have not previously encountered objects (an index of place memory) and for familiar objects in contexts different from those in which the objects were originally encountered (an index of context memory). In this experiment, rats with cytotoxic lesions of the hippocampal formation were tested on all three versions of the novelty-preference paradigm, with a 5-min retention interval between the familiarization and test phases. Rats with sham lesions displayed a novelty preference on all three trial types, whereas the rats with hippocampal lesions displayed a novelty preference on Object trials but did not discriminate between the objects on Place trials or Context trials. The findings indicate that hippocampal damage impairs memory for contextual or spatial aspects of an experience, whereas memory for objects that were part of the same experience are left relatively intact.     

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.     

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.     

Stress, self-esteem, and suicidal ideation in late adolescents

The relationships among stress, self-esteem, and suicidal ideation in late adolescents were examined in a group of college students. Multiple regression analysis indicated that both stress and self-esteem were significantly related to suicidal ideation; low self-esteem and stressful life events significantly predicted suicidal ideation. The hypothesis that self-esteem would moderate the effects of life stressors on suicidal ideation was supported at the .06 level. A significant minority of the sample indicated having thoughts severe enough to be classified as clinical suicidal ideation. In general, participants who had experienced negative life events in the 6 to 12 months prior to participating in the study had lower self-esteem than those who had similar stresses within the prior six months. However, the opposite was true for clinical suicidal ideators; those who experienced negative life stressors recently had lower self-esteem than those who experienced negative life events six months to a year in the past.     

Exploring the hand test with medically ill children and adolescents

Pediatric psychologists use the tools of assessment to evaluate the psychological functioning of youth with chronic and acute medical illnesses. This study is an exploration of the use of a performance-based measure, the Hand Test (HT; Wagner, 1983), with pediatric medical patients. A sample of medical inpatients (n = 27) and psychiatric outpatients (n = 24) were administered the HT, a self-report measure, and a parent-report behavior rating scale. Results indicate that the psychiatric group scored higher than the medical group on HT Aggression, Withdrawal, and Pathological scores. The Aggression (d = 0.90) and Pathological (d = 0.80) variables were particularly robust in differentiating between groups, but the Crippled variable did not differ between groups. Hierarchical logistic regression demonstrated the incremental validity of the HT over behavior ratings alone in the classification of clinical groups. Analyses indicated that the HT can add important information in the differentiation of medically ill children from those with psychological disturbance.