Where am I? Distal cues use requires sensitivity to start location change in the rat

Place learning is impaired when a single plus maze is moved between adjacent locations 33-120 cm apart. This maze translation creates distinct start locations but maintains a single goal location with respect to distal cues. Hippocampal cell recording data suggest the majority of place fields are tied to apparatus boundaries, not to distal cues, when an apparatus is moved these distances to the left or right. Thus, rats may fail to appreciate the existence of multiple start locations with respect to distal cues when the maze is moved in this way and their start location on the surface is constant. Performance on the single plus maze problem was improved when texture cues were correlated with different start locations. Place learning was supported when multiple start locations were provided on a single large surface (double plus maze), even though rats did not explore the entire surface. Place learning was also supported when random extensions were added to a double plus maze such that start locations, relative to surface boundaries, were not informative as to goal location. This outcome suggests sensitivity to multiple start locations is required for distal cue use in translational place problems.     

Cross-national comparisons of the association between alcohol consumption and deliberate self-harm in adolescents

How differences in drinking patterns may affect the impact of alcohol consumption on deliberate self-harm among adolescents is explored in this international comparative study. Schools in Australia, Belgium, England, Hungary, Ireland, the Netherlands, and Norway (N = 30,532) were surveyed. In all countries the risk of deliberate self-harm was significantly elevated among adolescents who reported some or numerous episodes of intoxication, controlling for confounding factors. The results support the assumption that intoxication is significantly related to the association between alcohol consumption and deliberate self-harm in adolescents.     

The analysis of three-way contingency tables by three-mode association models

TheRC(M) association model (Goodman, 1979, 1985, 1986, 1991) is useful for analyzing the relationship between the variables of a 2-way cross-classification. The models presented here are generalizations of theRC(M) association model for 3-way tables. The family of models proposed here, 3-mode association models, use Tucker's 3-mode components model (Tucker, 1964, 1966; Kroonenberg, 1983) to represent either the three factor interaction or the combined effects of two and three factor interactions. An example from a study in developmental psychology (Kramer & Gottman, 1992) is provided to illustrate the usefulness of the proposed models.I thank Stanley Wasserman, Laurie Kramer, Ulf Böckenholt, Larwence Hubert, Jeffrey Tanaka, and five anonymous reviewers for valuable comments.     

Relationship of temporal lobe volumes to neuropsychological test performance in healthy children

Ecological validity of neuropsychological assessment includes the ability of tests to predict real-world functioning and/or covary with brain structures. Studies have examined the relationship between adaptive skills and test performance, with less focus on the association between regional brain volumes and neurobehavioral function in healthy children. The present study examined the relationship between temporal lobe gray matter volumes and performance on two neuropsychological tests hypothesized to measure temporal lobe functioning (visual perception-VP; peabody picture vocabulary test, third edition-PPVT-III) in 48 healthy children ages 5-18 years. After controlling for age and gender, left and right temporal and left occipital volumes were significant predictors of VP. Left and right frontal and temporal volumes were significant predictors of PPVT-III. Temporal volume emerged as the strongest lobar correlate with both tests. These results provide convergent and discriminant validity supporting VP as a measure of the "what" system; but suggest the PPVT-III as a complex measure of receptive vocabulary, potentially involving executive function demands.     

Academic performance as a perceived function of ability and effort

Subjects made predictions of the grade point averages of hypothetical students who varied over complete continua of scholastic ability and effort. Subjects in Study 1 made their predictions on the implicit assumption that target students were drawn from a student body chosen via selective admissions criteria. Study 2 subjects assumed that the ability range was one resulting from a first-come, first-served open-admissions policy. Although the ability assumption inductions, as intended, led to performance level predictions that were differently dispersed, the basic patterns of subjects' predictions were essentially the same in both studies: For the overwhelming majority of subjects, ability and effort were perceived to affect scholastic performance additively rather than multiplicatively, thus contradicting the suggestions of previous theory. In addition, students with high ability were anticipated to perform reasonably well even when exerting practically no effort. Theoretical interpretations and practical implications of these results are introduced and discussed.This research was supported by Grant MH 27000 from the National Institute of Mental Health. It is a pleasure to acknowledge the capable assistance of Philip Johnson in the running of subjects and analysis of data for the reported studies.     

Does a quarterlife crisis exist?

In this study, the authors examined quarterlife crisis, defined in the popular press as an identity crisis that leaves recent college graduates depressed, anxious, and full of doubt. To determine if a unique crisis exists, 4 groups of young adults (recent high school [n = 23] and college [n = 117] graduates in the workforce, present undergraduate [n = 75], and graduate [n = 57] students) completed self-report measures assessing identity development, future time perspective, social support, coping, depression, anxiety, and job and life satisfaction. No support was found for a quarterlife crisis among these 4 groups. Working high school graduates displayed the highest anxiety, followed by present undergraduates. Depression was predicted by family support and identity commitment. Job satisfaction was associated with income and support from friends. Life satisfaction was associated with income, social support from friends and family, and identity commitment.     

Mitral cell beta1 and 5-HT2A receptor colocalization and cAMP coregulation: a new model of norepinephrine-induced learning in the olfactory bulb

In the present study we assess a new model for classical conditioning of odor preference learning in rat pups. In preference learning beta(1)-adrenoceptors activated by the locus coeruleus mediate the unconditioned stimulus, whereas olfactory nerve input mediates the conditioned stimulus, odor. Serotonin (5-HT) depletion prevents odor learning, with 5-HT(2A/2C) agonists correcting the deficit. Our new model proposes that the interaction of noradrenergic and serotonergic input with odor occurs in the mitral cells of the olfactory bulb through activation of cyclic adenosine monophosphate (cAMP). Here, using selective antibodies and immunofluorescence examined with confocal microscopy, we demonstrate that beta(1)-adrenoceptors and 5-HT(2A) receptors colocalize primarily on mitral cells. Using a cAMP assay and cAMP immunocytochemistry, we find that beta-adrenoceptor activation by isoproterenol, at learning-effective and higher doses, significantly increases bulbar cAMP, as does stroking. As predicted by our model, the cAMP increases are localized to mitral cells. 5-HT depletion of the olfactory bulb does not affect basal levels of cAMP but prevents isoproterenol-induced cAMP elevation. These results support the model. We suggest the mitral-cell cAMP cascade converges with a Ca(2+) pathway activated by odor to recruit CREB phosphorylation and memory-associated changes in the olfactory bulb. The dose-related increase in cAMP with isoproterenol implies a critical cAMP window because the highest dose of isoproterenol does not produce learning.     

Perceptual prioritization of self-associated voices

Information associated with the self is prioritized relative to information associated with others and is therefore processed more quickly and accurately. Across three experiments, we examined whether a new externally-generated voice could become associated with the self and thus be prioritized in perception. In the first experiment, participants learned associations between three unfamiliar voices and three identities (self, friend, stranger). Participants then made speeded judgements of whether voice-identity pairs were correctly matched, or not. A clear self-prioritization effect was found, with participants showing quicker and more accurate responses to the newly self-associated voice relative to either the friend- or stranger- voice. In two further experiments, we tested whether this prioritization effect increased if the self-voice was gender-matched to the identity of the participant (Experiment 2) or if the self-voice was chosen by the participant (Experiment 3). Gender-matching did not significantly influence prioritization; the self-voice was similarly prioritized when it matched the gender identity of the listener as when it did not. However, we observed that choosing the self-voice did interact with prioritization (Experiment 3); the self-voice became more prominent, via lesser prioritization of the other identities, when the self-voice was chosen relative to when it was not. Our findings have implications for the design and selection of individuated synthetic voices used for assistive communication devices, suggesting that agency in choosing a new vocal identity may modulate the distinctiveness of that voice relative to others.