The universal nature of human intelligence: Evidence from games

Mentally retarded individuals have relatively greater difficulty in dealing with strategic games and puzzles than with many other tasks. Consequently, it is of interest to find that strategic games have been played since ancient times, are played throughout the world, and that players who excel are frequently considered wise. Hidden within the more obvious differences between cultures, strategic games are an invariant expression of certain universal intellectual traits.     

Sex differences in realization of individual potential for achievement

Data from 4035 participants in Project TALENT were analyzed to examine the extent to which known sex differences in achievement held up when early potential for achievement was contolled. Original TALENT data, consisting of information on socioeconomic background, cognitive abilities, and educational and occupational aspirations, were collected in 1960 when members of the study sample were in Grade 9. Follow-up surveys measuring participants' educational and occupational attainment were conducted at 1, 5, and 11 years after the date of participants' expected graduation from high school. Women had higher high school grades and scored higher on a composite of academic ability tests taken in Grade 9 than did men. However, by 11 years after high school, men had acquired more education and were earning more money on the job. Sex differences in realization of achievement potential were found across all socioeconomic levels. At least part of the reason behind women's relative failure to translate potential into achievement may lie in the greater conflict, for women, between the roles of spouse/parent and the roles of student/worker: variables measuring the onset, duration, and extent of family-related commitments were more strongly related to female than to male realization of potential. Sex differences in achievement grew larger between the 5- and 11-year follow-ups as a greater proportion of women in the study sample became wives and mothers. The widening of the sex gap in achievement during this period was particularly pronounced among the subgroup of individuals who were in the top quartile of potential in Grade 9.     

Meditation,personality and arousal

A questionnaire survey of people who had learned a technique of meditation was carried out to assess persistence with practice, perceived effects of meditation practice and subjective experiences during meditation. The results suggested that a significant proportion give up meditating (42.9%) and that the subjective experience of meditation was similar to that of the hypnagogic state. Reported effects of meditation were generally physiological and psychological benefits related to relaxation.A personality questionnaire was also distributed and the results suggested that those attracted to meditation are significantly more neurotic and introverted than the general population but that those who continue with meditation are significantly less neurotic than those who give up their practice.These findings are discussed in terms of regression effects and in relation to a theory of personality and arousal.     

A twin study of personality and temperament during middle childhood

In a study of 105 same-sex twin pairs, ages 7 to 10 years, maternal ratings on 23 bipolar scales yielded six factors designated as compliant morality, applied cognitive, sociability, emotionality, tough-mindedness, and activity-distractibility. Analyses by twin pairs (68 identical, 37 fraternal) indicated that correlations for identical pairs were significantly higher than fraternal pairs on all but one factor: tough-mindedness. Profile analyses for the six factors indicated that the profiles of scores across the factors were more concordant for the identical twin pairs. Correlations obtained from the individual scales produced differences between the identical and fraternal twin pairs as well. Overall, the data suggested that several components and the total organization of those components of personality and temperament are genetically influenced.     

Unilateral agraphia after section of the posterior half of the truncus of the corpus callosum

Children ranging in age from 3 to 12 tapped on a morse key with their index finger as fast as possible. After a control test, they concurrently tapped and recited a nursery rhyme, recited animal names, and memorized shapes. Previous results suggested that more interference in a motor task results from attempting at the same time to perform another task controlled by the same, than by a different, hemisphere. Right-handed tapping and talking both used left hemisphere space; left-handed tapping and talking were controlled by different hemispheres. Relative to silent tapping concurrent talking caused a greater drop in right-hand tapping rate than in left-hand tapping rate in both the rhyme and animal conditions. Interference by shape memorizing was equal across hands. The differential effect of speaking on right-hand preference indicates the left lateralization of speech output control. The size of this effect did not vary with increasing grade level. The findings support the view that speech output control is fully lateralized at least by age 3 years.     

Verbal and nonverbal recognition memory in aphasic and nonaphasic stroke patients

The ability to retain lists of verbal and nonverbalizable items across recurrent recognition tasks was tested in three groups: (1) stroke patients with a left-brain lesion and aphasia, (2) stroke patients with a right-brain lesion and left hemiplegia, and (3) nonneurologically impaired outpatients. As determined with signal detection measures, aphasics were deficient in discriminating words that were to be remembered from those that were not; their recognition of nonverbal visual (geometric art) or auditory (bird calls) patterns, however, was unimpaired. Left hemiplegics showed the opposite pattern. After a long-term interval (<10 min), correct recognition of words was diminished in all groups whereas recognition of visual patterns increased. Both groups of stroke patients adopted material-specific decision criteria which in part accounted for the dissociation of verbal and nonverbal recognition memory by laterality of lesion. Item analysis indicated that aphasics' verbal memory difficulties were affected by acoustic-semantic confusion of list words.