Childhood intelligence,locus of control and behaviour disturbance as determinants of intergenerational social mobility: British Cohort Study 1970

Determinants of intergenerational social mobility were examined in 8287 men from the British Cohort Study 1970. Confirming previous research, parental social class, childhood intelligence, and educational qualifications were the strongest predictors of occupational social class at the age of 30. Locus of control and childhood behaviour disturbance had independent significant effects and accounted for additional amounts of variance. Self-esteem had only a trivial influence on social mobility. Structural equation modelling using full information maximum likelihood estimation demonstrated that: educational qualifications mediated other predictors' effects, accounting for the greatest amount of variance in people's own social status attainment; there was a substantial overlap of childhood behavioural disturbance, intelligence, and locus of control; there were effects of parental social class on own occupational social class attainment. Intergenerational social mobility is determined by a nexus of inter-correlated variables whose independent effects remain difficult to disentangle.     

Letter and Category Fluency in Normal Elderly Participants: a Population-Based Study

We studied variables influencing category and letter fluency in a large population-based sample of elderly participants. Letter and category fluency tasks were administered to 1133 unselected non-demented elderly participants in the Paquid cohort on normal and pathological aging. Age, education, principal lifetime occupation and depressive symptomatology independently influenced both category and letter fluency, while gender influenced only category fluency. A conceptualization measure (similarities) was found to influence fluency results mostly through education and prior occupation.     

Near-term fetuses process temporal features of speech

The perception of speech and music requires processing of variations in spectra and amplitude over different time intervals. Near-term fetuses can discriminate acoustic features, such as frequencies and spectra, but whether they can process complex auditory streams, such as speech sequences and more specifically their temporal variations, fast or relatively slow acoustic variations, is unclear. We recorded the cardiac activity of 82 near-term fetuses (38 weeks GA) in quiet sleep during a silent control condition and four 15 s streams presented at 90 dB SPL Leq: two piano melodies with opposite contours, a natural Icelandic sentence and a chimera of the sentence--all its spectral information was replaced with broadband noise, leaving its specific temporal variations in amplitude intact without any phonological information. All stimuli elicited a heart rate deceleration. The response patterns to the melodies were the same and differed significantly from those observed with the Icelandic sentence and its chimera, which did not differ. The melodies elicited a monophasic heart rate deceleration, indicating a stimulus orienting reflex while the Icelandic and its chimera evoked a sustained lower magnitude response, indicating a sustained attentional response or more focused information processing. A conservative interpretation of the data is that near-term fetuses can perceive sound streams and the rapid temporal variations in amplitude that are specific to speech sounds with no spectral variations at all.     

Are life episodes replayed during dreaming?

New phenomenological data demonstrate that integrated life episodes are incorporated in no more than 1-2% of dream reports. This appears to be at odds with the replay of temporally sequenced memory at the level of neuronal ensembles observed in some animals during sleep. This result will constrain emerging ideas on memory reactivation during sleep and the role of sleep in memory consolidation.     

Impact of executive dysfunctions on episodic memory abilities in patients with ruptured aneurysm of the anterior communicating artery

Executive and memory dysfunctions are among the most frequently reported deficits following a ruptured aneurysm of the anterior communicating artery (ACoA). In order to study the impact of the dysexecutive syndrome on episodic and semantic memory, the data obtained from 59 ACoA patients were examined retrospectively. All patients were assessed on a variety of episodic memory tests (Rey Auditory-Verbal Learning Test, Rey Complex Figure Test, Weschler Memory Scale), semantic memory (verbal fluency), and standardized tests of executive functions (Trail Making Test, Maze tests, Wisconsin Card Sorting Test). There was a strong positive correlation between executive dysfunction and retrieval difficulties in episodic and semantic memory tasks. Comparisons of subgroups of patients with high and low frontal lobe functioning on delayed recall and recognition revealed a significant group X condition interaction in addition to significant group and condition main effects. ACoAs patients with low frontal lobe functioning were particularly deficient in free recall (immediate and delayed) while recognition was equally well preserved in the two subgroups. Neither subgroup presented with an abnormal forgetting over time suggesting a retrieval deficit rather than a true retention impairment.     

Effects of multiple exposures to D-cycloserine on extinction of conditioned fear in rats

Previous research has shown that an acute, post-training injection of D-cycloserine (DCS) facilitates extinction of conditioned fear in rats; however, the effects of multiple exposures to DCS in this situation are not known. In Experiment 1, rats were conditioned (light-shock pairings) and 24 h later given six extinction (light-alone) trials followed by an injection of DCS (15 mg/kg) or saline. The next day, all rats were tested for light-elicited freezing. In Experiment 2, the effect of DCS on extinction was tested in the same manner, except that rats were pre-exposed to DCS (0, 1, or 5 injections) just prior to conditioning. In Experiment 3, rats received five pre-exposures of DCS but conditioning occurred either 2 or 28 days after the last pre-exposure. The results showed that DCS facilitated extinction of conditioned freezing to the light CS when no drug pre-exposure had occurred, but pre-exposure to DCS just prior to conditioning disrupted the facilitation of extinction effect. When 28 days were interposed between pre-exposure and conditioning, the facilitatory effects of DCS on extinction were restored. These findings suggest that DCS has significant clinical value but that behavioral desensitization may occur with multiple exposures; however, desensitization is not permanent and is reduced by the passage of time.