Not all executive functions are related to intelligence

Accumulating evidence suggests that executive functions (EFs) are related to intelligence, despite neuropsychological results initially considered evidence of no such relation. However, findings that EFs are not unitary raise the issue of how intelligence relates to different EFs. This study examined the relations of fluid and crystallized intelligence and Wechsler Adult Intelligence Scale IQ to three separable EFs--inhibiting prepotent responses (inhibiting), shifting mental sets (shifting), and updating working memory (updating)--in young adults. Updating was highly correlated with the intelligence measures, but inhibiting and shifting were not. Furthermore, in structural equation models controlling for the inter-EF correlations, updating remained strongly related to intelligence, but the relations of inhibiting and shifting to intelligence were small and not significant. The results indicate that intelligence measures differentially relate to these three EFs, suggesting that current intelligence measures do not equally assess a wide range of executive control abilities likely required for many "intelligent" behaviors.     

A simple device for detecting saccades and judging their intervals

A simple device is described with which the occurrence of saccades can be detected and their intervals classified by reference intervals determined by experimental requirements. The device reliably detects saccades of greater than 2 deg.     

Constraints on using the dual-task methodology to specify the degree of central executive involvement in cognitive tasks

The dual-task paradigm has been used to examine the role of the central executive in various cognitive tasks. In these studies, performance decrements in primary cognitive tasks performed concurrently with secondary executive tasks have been interpreted as evidence for the involvement of the central executive in those primary tasks. In the present study, we examined the effects of different secondary tasks on performance of three psychometric visuospatial tasks. The decrement in performance of these tasks when they were paired with secondary executive tasks was smallest for the psychometric task considered to most heavily involve the central executive and largest for the task considered least demanding of executive mechanisms. We propose that, when applied to the assessment of central executive involvement, the prevalent simple dual-task logic does not always apply. Special conditions that limit the application of the dual-task methodology include two inherently related factors--a response selection bottleneck and a strategic tradeoff between primary and secondary tasks.     

Is approximate numerical judgment truly modality-independent? Visual, auditory, and cross-modal comparisons

The numerosity of any set of discrete elements can be depicted by a genuinely abstract number representation, irrespective of whether they are presented in the visual or auditory modality. The accumulator model predicts that no cost should apply for comparing numerosities within and across modalities. However, in behavioral studies, some inconsistencies have been apparent in the performance of number comparisons among different modalities. In this study, we tested whether and how numerical comparisons of visual, auditory, and cross-modal presentations would differ under adequate control of stimulus presentation. We measured the Weber fractions and points of subjective equality of numerical discrimination in visual, auditory, and cross-modal conditions. The results demonstrated differences between the performances in visual and auditory conditions, such that numerical discrimination of an auditory sequence was more precise than that of a visual sequence. The performance of cross-modal trials lay between performance levels in the visual and auditory conditions. Moreover, the number of visual stimuli was overestimated as compared to that of auditory stimuli. Our findings imply that the process of approximate numerical representation is complex and involves multiple stages, including accumulation and decision processes.     

Developmental trajectories in toddlers' self-restraint predict individual differences in executive functions 14 years later: a behavioral genetic analysis

We examined whether self-restraint in early childhood predicted individual differences in 3 executive functions (EFs; inhibiting prepotent responses, updating working memory, and shifting task sets) in late adolescence in a sample of approximately 950 twins. At ages 14, 20, 24, and 36 months, the children were shown an attractive toy and told not to touch it for 30 s. Latency to touch the toy increased with age, and latent class growth modeling distinguished 2 groups of children that differed in their latencies to touch the toy at all 4 time points. Using confirmatory factor analysis, we decomposed the 3 EFs (measured with latent variables at age 17 years) into a Common EF factor (isomorphic to response inhibition ability) and 2 factors specific to updating and shifting. Less-restrained children had significantly lower scores on the Common EF factor, equivalent scores on the Updating-Specific factor, and higher scores on the Shifting-Specific factor than did the more-restrained children. The less-restrained group also had lower IQ scores, but this effect was entirely mediated by the EF components. Twin models indicated that the associations were primarily genetic in origin for the Common EF variable but split between genetics and nonshared environment for the Shifting-Specific variable. These results suggest a biological relation between individual differences in self-restraint and EFs, one that begins early in life and persists into late adolescence.     

Normal patterns of déjà experience in a healthy, blind male: challenging optical pathway delay theory

We report the case of a 25-year-old healthy, blind male, MT, who experiences normal patterns of déjà vu. The optical pathway delay theory of déjà vu formation assumes that neuronal input from the optical pathways is necessary for the formation of the experience. Surprisingly, although the sensation of déjà vu is known to be experienced by blind individuals, we believe this to be the first reported application of this knowledge to the understanding of the phenomenon. Visual input is not present in MT, yet the experiences he describes are consistent with reports in the literature of déjà vu occurrence in sighted people. The fact that blind people can experience déjà vu challenges the optical pathway delay theory, and alternative causes are briefly discussed.     

Inner speech as a retrieval aid for task goals: the effects of cue type and articulatory suppression in the random task cuing paradigm

Articulatory suppression has been shown to increase switch costs in the list paradigm (e.g., [J. Exp. Psychol.: General 130 (2001) 641, J Memory Language 48 (2003) 148]). The present dual-task study examined whether this effect generalizes to the random task cuing paradigm. Participants performed color or shape judgments according to explicit word cues (COLOR or SHAPE) or less transparent letter cues ( C for the color task and S for the shape task). In the word cue condition, the switch cost was equivalent for the articulatory suppression and the control (no dual-task) conditions, but, in the letter cue condition, the switch cost was significantly greater for the articulatory suppression condition than for the control condition. These results suggest that inner speech may be recruited as a tool for retrieving and activating the relevant task goal when the task cue is not transparent and hence imposes nonnegligible retrieval demand.     

ÉTUDE INTERCULTURELLE DES PRÉFÉRENCES MUSICALES

The question of socio-cultural relativism or universalism in aesthetic judgment is dealt with in a cross-cultural study of musical preferences. Four groups of subjects were compared: Japanese expert musicians, French professional musicians, French students in music and French non-musician students. Their task was to state their preference for one of the elements in ten pairs of excerpts of traditional Japanese music, representing three levels of complexity (Koto, Trio, Gagaku). In addition, the subjects were asked to give a general appreciation of the three styles. The analysis of the preferences was performed in three ways: intra-group and inter-groups variabilities were computed as well as the variability due to the musical style. The results can be summarized as follows: as far as a group judgment is possible in one or another culture (intra-group agreement), the preferences of two culturally different groups do not contrast as long as the judgment concerns rather simple objects; the degree of inter-cultural agreement, far from increasing with musical competence, decreases. On the other hand, the judgments of more complex pieces show an agreement only in groups with musical skill and, in this case, the preference of Japanese and French musicians are contrasting. Finally, it is pointed out that a minimal attractiveness of the material presented is necessary to obtain from the subjects valid comparisons instead of artificial.     

Is Trait Rumination Associated with the Ability to Generate Effective Problem Solving Strategies? Utilizing Two Versions of the Means-Ends Problem-Solving Test

This study examined the relationship between trait rumination and the effectiveness of problem solving strategies as assessed by the Means-Ends Problem-Solving Test (MEPS) in a nonclinical population. The present study extended previous studies in terms of using two instructions in the MEPS: the second-person, actual strategy instructions, which has been utilized in previous studies on rumination, and the third-person, ideal-strategy instructions, which is considered more suitable for assessing the effectiveness of problem solving strategies. We also replicated the association between rumination and each dimension of the Social Problem-Solving Inventory-Revised Short Version (SPSI-R:S). Japanese undergraduate students (N = 223) completed the Beck Depression Inventory-Second Edition, Ruminative Responses Scale (RRS), MEPS, and SPSI-R:S. One half of the sample completed the MEPS with the second-person, actual strategy instructions. The other participants completed the MEPS with the third-person, ideal-strategy instructions. The results showed that neither total RRS score, nor its subscale scores were significantly correlated with MEPS scores under either of the two instructions. These findings taken together with previous findings indicate that in nonclinical populations, trait rumination is not related to the effectiveness of problem solving strategies, but that state rumination while responding to the MEPS deteriorates the quality of strategies. The correlations between RRS and SPSI-R:S scores indicated that trait rumination in general, and its brooding subcomponent in particular are parts of cognitive and behavioral responses that attempt to avoid negative environmental and negative private events. Results also showed that reflection is a part of active problem solving.     

A novel lattice correspondence of B19 → B19′ transformation in Ti–Ni–Cu shape memory alloy thin film

In this study, we found a novel lattice correspondence of the B19–B19′ transformation in a Ti–Ni–Cu thin film: (1?1?1)_B19′//(0?0?1)_B19, [0, 1, 1]_B19′//[1?0?0]_B19. Near the coarse precipitate and the grain boundaries, the B19′ martensite forms with the novel lattice correspondence to product the (1?1?1) type I twinning instead of the usual (0?0?1) compound twinning. Crystallographic analyses show that the novel lattice correspondence results from the local stress concentration.