Cue-framing effects in source remembering: A memory misattribution model

During source remembering, selectively emphasizing one source in the retrieval query “Is this item from Source A?” can yield different accuracy than emphasizing the alternate source in “Is this item from Source B?” even if those are the only two possible origins. One account of this cue-framing effect holds that it reflects different active monitoring strategies encouraged by the two cue frames. An item memory misattribution (IMM) model instead assumes that this effect reflects the uncontrolled use of item recognition during confirmatory source judgments, and an IMM model simulation predicted a quantitative relationship between recognition levels and the cue-framing effect. Experiments 1 and 3 confirmed these predictions by using study repetitions to manipulate recognition levels, and Experiments 2 and 3 also demonstrated the effect with new source tasks not previously considered. The data suggest that, in addition to qualitative monitoring strategies, subjects also use the availability of item memory in a heuristic fashion during confirmatory source attributions.     

Starting with the "right" foot minimizes sprint start time

Although asymmetries in hand and foot performance have been examined using a variety of movement tasks that require the fine control of the timing and amplitude of force generation, foot asymmetries in a functional gross motor movement task, such as the track and field sprint start, have yet to be examined. Twenty individuals (10 experienced, 10 inexperienced) were assessed for pedal asymmetries using the track and field sprint start. Each participant performed 48 starts (24 right foot starts and 24 left foot starts). The pattern of pedal asymmetries was consistent with that of manual asymmetries in that a left foot (i.e., left foot in rear position) reaction time advantage was found while there was a right foot (i.e., right foot in rear position) advantage for movement time and total response time (time from stimulus presentation until the end of the movement). These results are consistent with a right hemisphere specialization for spatio-temporal and attentional processes, and a left hemisphere specialization for movement execution.     

Bright children become enlightened adults

We examined the prospective association between general intelligence (g) at age 10 and liberal and antitraditional social attitudes at age 30 in a large (N= 7,070), representative sample of the British population born in 1970. Statistical analyses identified a general latent trait underlying attitudes that are antiracist, pro-working women, socially liberal, and trusting in the democratic political system. There was a strong association between higher g at age 10 and more liberal and antitraditional attitudes at age 30; this association was mediated partly via educational qualifications, but not at all via occupational social class. Very similar results were obtained for men and women. People in less professional occupations-and whose parents had been in less professional occupations-were less trusting of the democratic political system. This study confirms social attitudes as a major, novel field of adult human activity that is related to childhood intelligence differences.     

More intelligent, more dependable children live longer: a 55-year longitudinal study of a representative sample of the Scottish nation

The associations of childhood intelligence and dependability with adult mortality were examined in 1,181 people who were representative of the Scottish nation. Participants were born in 1936 and were followed for mortality from 1968 through early 2003. Higher intelligence and greater dependability were independent, significant predictors of lower mortality: With both factors entered together, the hazard ratio (HR) was 0.80 (95% confidence interval, CI: 0.65-0.99, p= .037) per standard deviation increase in intelligence and 0.77 (95% CI: 0.63-0.94, p= .009) per standard deviation increase in dependability. Children in the lower half of the distributions for intelligence and dependability were more than twice as likely to die compared with those who scored in the top half for both these measures (HR = 2.82; 95% CI: 1.81-4.41). Studied together for the first time in a representative sample, these two psychological variables are independent life-course risk factors for mortality. It is important to discover the mechanisms by which they influence survival.     

Long-term effects of prior cocaine exposure on Morris water maze performance

Cocaine addiction is associated with long-term cognitive alterations including deficits on tests of declarative/spatial learning and memory. To determine the extent to which cocaine exposure plays a causative role in these deficits, adult male Long-Evans rats were given daily injections of cocaine (30 mg/kg/day x 14 days) or saline vehicle. Three months later, rats were trained for 6 sessions on a Morris water maze protocol adapted from Gallagher, Burwell, and Burchinal [Gallagher, M., Burwell, R., & Burchinal, M. (1993). Severity of spatial learning impairment in aging: development of a learning index for performance in the Morris water maze. Behavioral Neuroscience, 107, 618-626]. Rats given prior cocaine exposure performed similarly to controls on training trials, but searched farther from the platform location on probe trials interpolated throughout the training sessions and showed increased thigmotaxis. The results demonstrate that a regimen of cocaine exposure can impair Morris water maze performance as long as 3 months after exposure. Although the impairments were not consistent with major deficits in spatial learning and memory, they may have resulted from cocaine-induced increases in stress responsiveness and/or anxiety. Increased stress and anxiety would be expected to increase thigmotaxis as well as cause impairments in searching for the platform location, possibly through actions on ventral striatal dopamine signaling.     

Domain-specific and domain-general changes in children's development of number comparison

The numerical distance effect (inverse relationship between numerical distance and reaction time in relative number comparison tasks) has frequently been used to characterize the mental representation of number. The size of the distance effect decreases over developmental time. However, it is unclear whether this reduction simply reflects developmental changes in domain-general speed of processing and whether it is specific to numerical compared with non-numerical magnitude. To examine these open questions, we conducted a cross-sectional study with 6-, 7-, and 8-year-old children as well as adult college students. Participants performed comparisons on Arabic numerals, arrays of squares, squares of varying luminance and bars of varying height. To control for general age-related changes in reaction time, a measure of speed of processing was used as a covariate in the analysis. A significant developmental decrease in the distance effect was found across numerical and non-numerical comparison tasks over and above general changes in processing speed. However, this change was not found to differ as a function of format. These data suggest that developmental changes in the distance effect are reflective of changes in a domain-general comparison process, rather than domain-specific developmental changes in number representations. However, analysis of overall reaction times revealed significantly greater developmental changes for numerical relative to non-numerical comparison tasks. These findings highlight the importance of taking multiple measures into account when characterizing developmental changes in numerical magnitude processing. Implications for theories of numerical cognition and its development are discussed.     

The relation between scores on the Buss–Perry Aggression Questionnaire and aggressive acts,impulsiveness, competitiveness,dominance, and sexual jealousy

This paper examines the relation of the four subscales (physical, verbal, anger and hostility) of the Buss–Perry Aggression Questionnaire (BPAQ) to act‐based aggression questionnaires (involving same‐sex or partners as opponents, and direct or indirect aggression) and evolutionarily based predictors of aggression, using an online student sample. All aggression measures were moderately correlated with one another. The BPAQ physical and verbal scales were most closely related to act‐based measures of direct aggression to a same‐sex other and the hostility scale to indirect aggression to a same‐sex other. The evolutionary variables were less closely related to the BPAQ than were the act‐based measures. Dominance and sexual jealousy were predictors of BPAQ physical, verbal and anger, and impulsiveness was a significant predictor of anger. Aggr. Behav. 32:1–10, 2006. © 2006 Wiley‐Liss, Inc.