An investigation of hemisphere differences for moderately imageable words across high and low image contexts

The RVF/LH advantage typically found for high image nouns may be reduced or eliminated when they are mixed with other types of words, such as low image nouns ([Chiarello et al., 2001]). Global stimulus context thus appears to affect the distribution of processing across the hemispheres ( [Chiarello et al., 2001]). This idea was further investigated in the present study by presenting moderately imageable words (e.g., HOBBY) intermixed with either low or high image nouns. It was predicted that these medium image words would show a RVF advantage when mixed with high image nouns. However, this RVF advantage was expected to disappear when they were mixed with low image nouns, because the medium image words would be relatively more imageable in that context. This hypothesis was not supported, as similar RVF advantages were found for each imageability condition. It is suggested that more heterogenous stimulus distributions may be necessary for context-dependent alterations of cerebral asymmetries to occur.     

Marital discord and well-being in older adults: is the association confounded by personality?

The associations between marital discord and multiple measures of well-being (depression, anxiety, life satisfaction, and self-esteem) were evaluated in a population-based sample of 416 couples in which the husband was 65 years or older. Results indicated that greater marital discord was associated with greater depression and lower life satisfaction and self-esteem. Furthermore, the associations between marital discord and well-being remained significant when statistically controlling for the rival explanation of the Big Five personality traits. Finally, there was little evidence for gender differences in the magnitude of the associations between marital discord and well-being. Findings suggest that marital discord is an important correlate of multiple measures of well-being in older individuals and that this association is not confounded by the Big Five personality traits.     

Event understanding and memory in healthy aging and dementia of the Alzheimer type

Segmenting ongoing activity into events is important for later memory of those activities. In the experiments reported in this article, older adults' segmentation of activity into events was less consistent with group norms than younger adults' segmentation, particularly for older adults diagnosed with mild dementia of the Alzheimer type. Among older adults, poor agreement with others' event segmentation was associated with deficits in recognition memory for pictures taken from the activity and memory for the temporal order of events. Impaired semantic knowledge about events also was associated with memory deficits. The data suggest that semantic knowledge about events guides encoding, facilitating later memory. To the extent that such knowledge or the ability to use it is impaired in aging and dementia, memory suffers.     

Implicit memory, age, and time of day: paradoxical priming effects

Memory retrieval can occur by at least two routes: a deliberate one, as when one attempts to retrieve an event or fact, and an unintentional one, as when one's behavior is triggered by the past without one's knowledge or awareness. We assessed the efficacy of these retrieval systems as a function of circadian arousal and time of day. Evening-type younger adults and morning-type older adults were tested at either peak (morning for old; evening for young) or off-peak times on implicit and explicit stem completion (Experiment 1) or on implicit category generation (Experiment 2). Results for explicit stem-cued recall replicated better performance for each age group at its peak time. In stark contrast, implicit performance was better at off-peak than at peak times of day, raising the possibility that the processes that serve explicit and implicit retrieval are on different circadian schedules, and highlighting the need to consider individual differences in circadian arousal when assessing either memory system.     

Agency in the face of error

Experiencing oneself as the cause of an action is a fundamental building block for a sense of self. A recent study by Sato and Yasuda provides evidence that motor prediction contributes to the experience of agency. Their findings demonstrate that agency is experienced not only for intended, but also for erroneous, unintended actions. This extends our knowledge on the phenomenology of action, and raises questions about the relation between explicit reports and agency-related changes in sensation and perception.     

What underlies the neuropsychological pattern of irregular > regular past-tense verb production?

The disadvantage in producing the past tense of regular relative to irregular verbs shown by some patients with non-fluent aphasia has been alternatively attributed (a) to the failure of a specific rule-based morphological mechanism, or (b) to a more generalised phonological impairment that penalises regular verbs more than irregular owing to the on-average greater phonological complexity of regular past-tense forms. Guided by the second of these two accounts, the current study was designed to identify more specific aspects of phonological deficit that might be associated with the pattern of irregular > regular past-tense production. Non-fluent aphasic patients (N = 8) were tested on past-tense verb production tasks and assessed with regard to the impact of three main manipulations in other word-production tasks: (i) insertion of a delay between stimulus and response in repetition; (ii) presence/number of consonant clusters in a target word in repetition; (iii) position of stress within a bi-syllabic word in repetition and picture naming. The performance of all patients deteriorated in delayed repetition; but the patients with the largest discrepancy between regular and irregular past-tense production showed greater sensitivity to the other two manipulations. The phonological nature of the factors that correlated with verb-inflection performance emphasises the role of a phonological deficit in the observed pattern of irregular > regular.     

Aging, subjective experience, and cognitive control: dramatic false remembering by older adults

Recent research suggests that older adults are more susceptible to interference effects than are young adults; however, that research has failed to equate differences in original learning. In 4 experiments, the authors show that older adults are more susceptible to interference effects produced by a misleading prime. Even when original learning was equated, older adults were 10 times as likely to falsely remember misleading information and were much less likely to increase their accuracy by opting not to answer under conditions of free responding. The results are well described by a multinomial model that postulates multiple modes of cognitive control. According to that model, older adults are likely to be captured by misleading information, a form of goal neglect or deficit in inhibitory functions.     

"Economic man" in cross-cultural perspective: behavioral experiments in 15 small-scale societies

Researchers from across the social sciences have found consistent deviations from the predictions of the canonical model of self-interest in hundreds of experiments from around the world. This research, however, cannot determine whether the uniformity results from universal patterns of human behavior or from the limited cultural variation available among the university students used in virtually all prior experimental work. To address this, we undertook a cross-cultural study of behavior in ultimatum, public goods, and dictator games in a range of small-scale societies exhibiting a wide variety of economic and cultural conditions. We found, first, that the canonical model - based on self-interest - fails in all of the societies studied. Second, our data reveal substantially more behavioral variability across social groups than has been found in previous research. Third, group-level differences in economic organization and the structure of social interactions explain a substantial portion of the behavioral variation across societies: the higher the degree of market integration and the higher the payoffs to cooperation in everyday life, the greater the level of prosociality expressed in experimental games. Fourth, the available individual-level economic and demographic variables do not consistently explain game behavior, either within or across groups. Fifth, in many cases experimental play appears to reflect the common interactional patterns of everyday life.