Left-handedness in twin families: support of an environmental hypothesis

Information on handedness, assessed as writing-hand, was collected from 197 MZ twin pairs and 203 DZ twin pairs and from their parents, spouses, and children. Associations for pairs of relatives were studied by 2 X 2 tables, computing chi squared-values and tetrachoric correlations. Correlations of about .3 were obtained for mother-offspring and sibling pairs, while for cousins the correlation was .25 (in a small sample). No other significant associations were found, not even for twins. These results suggest only a small, if any, genetic effect, and only a small environmental between family effect, most of which seems to be a maternal effect. The lack of cotwin correlations and correlations for one of the twins with her/his ordinary brothers/sisters suggest the existence of an effect specific to twins, since the correlation for pairs of ordinary siblings is significant. Conclusions drawn from twin studies alone may be biased. The frequency of left-hand writers has increased from 1% to 10% in the different age groups born during the last century in Norway. This age effect is present mainly in hand writing and not so much in handedness generally, suggesting a decrease in cultural repression against left-hand writing.     

Vertical reversal and lateral reversal as components of inversion in recognition memory for upside-down faces

Subjects viewed upright photographs of faces, then attempted to recognize them unchanged, vertically reversed or inverted. In two of four conditions, hit scores were lower for inverted than vertically reversed faces, suggesting that lateral reversal is a meaningful component of inversion. The effect was not sufficiently strong, however, to overcome a generally high false-alarm rate for upside-down faces.     

Visual dominance in olfactory memory

The object of the present study was to verify the emergence of a 'visual dominance' effect in memory tests involving different sensory modes (sight and smell), brought about the preattentive mechanisms which select the visual sensory mode regardless of the recall task.     

Midline and off-midline tongue and right- and left-hand vibrotactile thresholds of stutterers and normal-speaking individuals

Vibrotactile thresholds for 7 male stutterers and 7 normal-speaking men (age range for both groups = 19 to 32 yr.) were obtained from the right, midline, and left sides of the lingual dorsum, and the thenar eminences of both hands. The stutterers showed slightly higher (less sensitive) mean thresholds than the normal speakers for all three lingual test sites. This was not the case for the thresholds obtained from both hands. The preliminary data suggest that oral peripheral sensory integrity might be somewhat different for stutterers than for normal-speaking individuals.     

Handedness and dementia

Some researchers have speculated that left-hand dominance is more prevalent among patients suffering from dementia of the Alzheimer's type which began prior to age 65 yr. and that, in those patients, the disease runs a more rapid course. In the present study, seven left-handed dementia patients were matched with seven right-handed dementia patients on the basis of age and years of education and were compared with regard to neuropsychological compromise. While the left-handed group was somewhat more impaired than the right-handed subjects, the difference between the two groups was not statistically significant.     

A FIELD STUDY OF APPLICANT REACTIONS TO EMPLOYMENT OPPORTUNITIES: DOES THE RECRUITER MAKE A DIFFERENCE?

Previous cross-sectional field and laboratory research has provided mixed results as to whether recruiter characteristics and behaviors influence applicant reactions to employment opportunities. The present research was conducted to examine the effect of recruiter characteristics using a pre-post study design in a naturally occurring setting. In addition, the effects of several potential moderators on recruiter influence were tested. Results indicated that recruiter characteristics had an impact on perceived job attributes, regard for job and company, and likelihood of joining the company. There was little evidence that the effect of recruiter characteristics was moderated by selected applicant, job, or interviewer variables.     

Temporal pattern of agonist-antagonist EMG activity during rapid limb movements in man

Analysis of elbow-extension movements, executed at maximal velocity, show positive correlations of timing of agonist-antagonist EMG activity with both movement velocity and displacement. Results indirectly support the notion that the antagonist musculature provides a braking force to arrest rapid limb movements.     

Social support versus companionship: effects on life stress, loneliness, and evaluations by others

In recent years, much interest has focused on delineating and contrasting specific functions of social relationships that contribute to psychological well-being. Five studies contrasted the roles of companionship and social support in buffering the effects of life stress, in influencing feelings of loneliness and social satisfaction, and in affecting others' judgments. Study 1 analyzed data from a community survey and found that companionship had a main effect on psychological well-being and a buffering effect on minor life stress, whereas social support had only a buffering effect on major life stress. Studies 2, 3, and 4 analyzed data from two college student samples and a different community survey to evaluate how companionship and social support contributed to relationship satisfaction and feelings of loneliness. The results of these studies indicated that companionship was the strongest predictor of these dimensions of social satisfaction. Study 5 used an experimental design to test the hypothesis that a deficit of companionship elicits more negative reactions from others than does a deficit of social support. This hypothesis received partial support. Considered together, the results of these studies suggest that companionship plays a more important and more varied role in sustaining emotional well-being than previous studies have acknowledged.