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We evaluated the effect of repeated use of the nonpreferred hand on young children’s manual preference by positioning toys in the left hemifield in egocentric coordinates to induce right-handed 4–5-year-olds to use their left hands spontaneously. We induced motor activities in the laterally biased workspace by presenting tasks in a ludic context over different days, similar to their daily kindergarten experience. Preceding and following these lateralized experiences, the children were tested on a task requiring reaching, grasping, and inserting cards into a slot. In the 1-day retention assessment, we found that repeated use of the nonpreferred left hand in the previous phase led to increased use of the left hand to perform the probing task. Following 14 days of rest, the children with induced left-hand experiences used exclusively their left hands to manipulate the leftmost card positions. We propose that repeated use of the nonpreferred left hand leads to increased confidence to plan left-handed movements for subsequent tasks.

In a recent paper, Mayolas Pi, Arrese, Aparicio, and Masià reported the absence of significant bilateral differences between legs in the average plantar pressure during walking in six- to seven-year-old children. However, the authors demonstrated bilateral differences in the distribution of plantar pressure during walking independent of foot preference in three tests: kicking a ball with precision, balancing on one foot, and jumping on one foot. From the results, Mayolas Pi et al. proposed that this asymmetric pattern of plantar pressure distribution is not caused by laterality. This paper suggests that the selected age range of participants and methods of diagnosing of laterality and data analysis could have significant effects on the results. Indeed, according to the literature, laterality in humans is a multidimensional trait with poor stabilization and conformity between different dimensions in preschool and younger school children.

The left hemisphere is usually predominant in manual skills and language, suggesting a link between hand dominance and language. Studies of autism spectrum disorder show atypical handedness; however, few have examined language-handedness associations. Handedness, assessed by task performance, and standardized receptive and expressive language tests were completed in 110 autism spectrum disorder children (96 boys; M age = 8.3 years, SD = 3.8) and 45 typically developing children (37 boys; M age = 8.6 years, SD = 4.3), 3 to 17 years of age. The autism spectrum disorder group had a lower handedness score (was less strongly lateralized) than the control group. In the autism spectrum disorder group, there was a small effect of handedness on language; right-handers had better language than non-right-handers. Results suggest poorer language prognosis may be associated with left- or mixed-handedness in autism spectrum disorder.

Twenty-three Japanese genuine left-handers were selected by a Laterality Quotient scale and asked to draw the letter S on their own temples and foreheads. The way they drew on the temples showed an asymmetry that was the mirror reversal of that of right-handers, as found in a previous study. Left-handers drew a reversed letter S on their right temple much more often than on the left temple, whereas right-handers drew them in reverse more often on the left temple. They also drew it in reverse on the forehead irrespective of their handedness.

Hand grip force adjustment errors to ascending and descending phases of a sinusoidal target force in a controlled force exertion (CFE) test were measured and the laterality of responses evaluated. 75 men ( M age = 19.6 yr., SD = 1.6) performed the CFE test after one practice trial by matching handgrip force to target level (5–25% of maximal grip force). The CFE errors in ascending and descending phases of the target force were calculated as the absolute differences between actual force and target force in each phase. There were significantly smaller CFE errors in the ascending phase for both dominant and non-dominant hands, but CFE error for the dominant hand was significantly smaller in both phases. Therefore, error in force exertion in the ascending and descending phases of the target force differed, and laterality influenced error in both phases.

Underlying sensorimotor factors, such as intermanual coupling, contributing to optimal laterality, long remain immature. Using the handmotor laterality blackboard, developmental change in symmetric bimanual motor function for 413 children in groups of 3 to 10 years of age shows synchronicity increased between groups 3 and 5 years of age; but between groups 5 and 7 years of age, given immature coupling, one hand may still disturb the movements of the other one. Between groups 7 and 9 years of age, the hands gradually stop disturbing each other and move independently and fluently. Changes in intermanual coupling with increasing unimanual independence represent expression of changing interhemispheric integration across groups. This promotes optimal laterality and task distribution between the hands. Maturation of the corpus callosum is inferred to be a factor in these ontogenetic changes which ultimately lead to optimal left hemisphere specialization for actions such as fluent writing.

This study assessed bilateral facilitation and laterality during counter-movement jumps. 23 NCAA Division-I athletes (13 men, 10 women) who participated in track and field volunteered to serve as participants and performed bilateral, right, and left leg countermovement jumps on a force plate. Dependent variables included jump height, reactive strength index, and time to stabilization. A one-way analysis of variance showed significant sex differences in single-leg and bilateral jump height and left leg and bilateral reactive strength index. No sex differences were found for time to stabilization. A repeated-measures analysis of variance indicated significant main effects for jump height and reactive strength index but not for time to stabilization. Bonferroni adjusted pairwise comparisons showed that bilateral jump height and reactive strength index values were different from the unilateral conditions. No differences were found between the right and left legs for jump height, reactive strength index, or time to stabilization. Results indicated no evidence of laterality as assessed by jump height, reactive strength index, and time to stabilization. Bilateral facilitation was found as assessed by jump height and reactive strength index. Time to stabilization demonstrated a bilateral deficit phenomenon.

Indications of earlier research are that individuals exhibiting a consistent hand preference are better coordinated on selected motor tasks than peers with inconsistent hand preference. The present study examined eye-hand coordination via inter- and intramodal matching behavior by handedness groups for 55 5- and 6-yr.-olds using the Pinboard Test. Analysis indicated the Consistent group scored better, leading to the speculation that children with consistent laterality may possess an advantage in interhemispheric communication, especially when the task requires coordination of both limbs.

We examined the vertical jump performance of each leg among 10 right-footed female ballet dancers with 1 yr. of international professional experience ( quadrilles: Opera ballerinas). Their mean age was 17.5 yr. ( SD = 03). The maximal height of the unilateral jump was recorded, and muscle mass was evaluated by biphotonic absorptiometry method. Muscle mass and maximal jump height were similar for the two legs. A strong inverse relation was found between the muscle mass of the right leg (67%) and maximal jump height ( r = −.81, p < .01) but not for the left leg. These results highlight a functional asymmetry and the effect of motor laterality in dance.

It is unclear whether the cortical representation of swallowing is lateralized to the left cerebral hemisphere, right hemisphere, or bilaterally represented. As dysphagia is common in acute stroke, it is important to elucidate swallowing lateralization to facilitate earlier detection of stroke patients who may be at greater risk for dysphagia and aspiration. In this study, a modified dual task paradigm was designed to study laterality of swallowing in a group of 14 healthy, young, right-handed, male adults. The subjects were studied at baseline and with interference. Baseline conditions, performed separately, were continuous swallowing, finger tapping using the right and left index fingers, and word repetition. Interference tasks, including tapping with the right index finger, tapping with the left index finger, and word repetition, were completed with and without swallowing. Finger-tapping rate was measured, and x-ray samples of the swallowing task were taped to measure swallowing rate and volume swallowed. At baseline, the rate of tapping the right index finger was significantly faster than that of the left index finger. There was a significant decline in the tapping rates of both left and right index fingers with swallowing interference. The volume per swallow was significantly reduced during the interfering language task of silent repetition. These results offer partial support for a bilateral representation of swallowing as well as suggest an important left hemispheric contribution to swallowing. However, it cannot be concluded that the left hemisphere is more important than the right, as a comparable right hemisphere task was not studied.

An asymmetry of anterior cerebral activation favoring the right hemisphere has been associated with dispositional negative affect including trait-anxiety, while the opposite appears true of cerebral asymmetry favoring the left hemisphere. It was hypothesized that an asymmetry of cerebral activation, as defined by scores on a measure of trait-anxiety, ipsilateral to the side of an anterior brain lesion would be associated with less efficient cognitive processing than greater activation in the hemisphere contralateral to the lesion. Patients with anterior left ( n = 16) or right ( n = 15) hemisphere lesions completed the State-Trait Anxiety Inventory and several neurocognitive tasks. Of the abilities tested, only Digit Span scores showed an interaction between side of lesion and presumed activation asymmetry. Patients with right- but not with left-hemisphere damage showed significant differences in working memory performance depending on the presumed direction of asymmetry of the two hemispheres, supporting the dual roles of the right hemisphere in affective processing and directed attention.

429 participants including elementary school children and high school students drew three pictures of themselves doing habitual actions: brushing the teeth, using chopsticks, and throwing a ball. Whether the hand used in the pictures corresponded to the actual preferred hand was assessed. Analyzing the drawings of 396 participants who stated a right-hand preference, the sex difference was significant as were changes across ages (grades). The number and percentage of the drawings of real images (corresponding to the actual preferred hand) were larger for boys than for girls and increased across grades. Girls and younger participants tended to draw mirror-image figures of their own actions.

The dual-task paradigm has been used extensively to study laterality, with concurrent verbalization interfering with right finger-tapping in right handers. Only a few studies have used this paradigm to study interference patterns in left handers and have found inconsistent results. The dual-task paradigm has not been used to study interference effects with concurrent verbalization and foot-tapping. The objective of this study was to use this paradigm to assess whether verbal interference produces different effects on finger- and foot-tapping rate for right handers as compared to left handers. 12 right-handed and 12 left-handed men were studied, each with uncrossed hand and foot dominance, i.e., all individuals were either right handed and right footed or left handed and left footed. Subjects performed finger- and foot-tapping tasks with and without verbal interference. A significant relationship was found between handedness and finger and foot-tapping rate; individuals with a stronger right-hand preference tended to tap at a higher rate on the right side and vice-versa. Analogous relationships were not found when participants were tapping and speaking concurrently. With verbal interference, both right and left handers had a significant asymmetric effect with a decremental response in right finger-tapping rate and a facilitative effect on left finger-tapping rate. In contrast, there was a bilateral decremental response in foot-tapping with verbal interference in both right and left handers. The implications of these findings are discussed with reference to cerebral laterality of language systems and to the differential organization and integration of the motor representations of the hand and the foot.

To demonstrate the positive effects of smoking on spatial-imagery processing, behavioral (hit ratio and reaction time) and physiological indices (EEGs and HR) were examined in 12 student volunteers. Subjects performed two spatial-imagery tasks, one mental rotation and the other mental paper-folding. The two tasks were performed before and after smoking and the results compared. Subjects participated in both control and smoking sessions. Reaction time decreased after smoking, while the hit ratio did not change. EEG contour maps derived from 12-channel records of the beta band showed activation of the frontal area during the spatial-imagery processing. After smoking, EEG laterality showed increased right-hemisphere dominance. These findings implied that smoking facilitated selective activation of the hemisphere and did not support Gilbert and Wesler's hypothesis of left-hemisphere priming. Psychophysiological mechanisms of the effects of smoking were discussed.

The bases for the preferential use of one ear are not clear. We investigated ear preference, asymmetry on a dichotic listening test and acuity dominance (laterality of hearing loss) in a sample of 51 patients with mild high frequency hardness of hearing. There was a higher correlation between measured ear preference and the measured acuity dominance than between ear preference and dichotic listening, suggesting a certain peripheral (cochlear) base for the ear preference.

The handedness preference (laterality) of 1,196 professionals grouped in nine professions previously reported using self-reported global handedness and scores on a modified Edinburgh Handedness Inventory was further defined by evaluating the association between profession and the 10 manual tasks of the inventory. The previously reported ranking of professions in order of increasing righchandedness of laterality score arose from the handedness of specific inventory tasks. A similar association was found for self-reported global handedness. The evidence continues to support the hypothesis of an association between handedness preference and specific aptitudes or skills in this sample of professional persons.

There are only a few studies in the literature concerning all four lateral preferences (handedness, footedness, eyedness, earedness) and presenting their interrelationships. Porac and Coren's 1981 inventory was used to assess hand, foot, eye, and ear preference in a German sample of 506 men and 430 women. A right sided preference was found for hand, foot, eye, and ear preference among 91%, 74%, 66%, and 63% of the sample, respectively. More men were left-handed and left-footed than women. There were no significant sex differences for eyedness and earedness. Correlations ranged from .22 between hand and eye laterality to .44 between hand and foot laterality.

A temporal motor defect in speech preparation and/or planning may contribute to the development of stuttering. This defect may be linked to a dysfunctional cortical-subcortical network at the level of the striatum. To determine whether structural differences exist and whether group differences are associated with stuttering severity or manual laterality, the caudate was measured in 14 children who stutter (CWS) and in a control group of right-handed boys, ages 8–13 years. There was a statistically significant hemisphere by group effect for caudate volume. CWS had reduced right caudate volume and atypical leftward asymmetry compared to controls. Nine of the 13 CWS with atypical caudate asymmetry had atypical manual laterality. These anomalies may represent a vulnerability that perturbs speech planning/preparation and contributes to inefficiencies in action-perception coupling that may be an indicator of stuttering susceptibility. These results suggest that right-handed boys who stutter may have a defect in the feedforward cortico-striato-thalamo-cortical networks.

This study examined the laterality of the supporting leg in postural stability during a one-leg stance test on an unstable moving platform and its practice effect. 30 male university students were evaluated using the omnidirection stability index (OSI) during a one-leg stance test on an unstable moving platform (three trials). The leg used when kicking a ball was defined as the manipulation leg (ML) and the supporting leg was defined as the non-manipulation leg (NML). According to the two-way repeated measures analysis of variance (ANOVA; trials × legs), a statistically significant difference was observed only on the leg factor, and OSI values of the second and third trials were less for the ML than the NML. The correlation between both legs was statistically significant but not high. The ML was superior to NML with regard to stability, and no practice effect with trials was evident in either leg. © Perceptual & Motor Skills 2013.

This study examined the association of nine patterns of limb preference (combination hand/foot), described as congruent or cross-lateral, with gross-motor agility of 302 4- to 6-yr.-old boys. Based on contemporary reports of handedness and motor coordination, it was hypothesized that persons exhibiting a right-hand/foot congruent pattern would outperform their peers in other groups. However, analyses indicated no significant differences on total motor performance between groups with different limb patterns. Further nonsupport of the hypothesis was evident since the best performance was exhibited by the mixed-hand/left-foot group. In view of past studies and these results, it appears that additional inquiry is warranted before any consensus regarding the association between limb laterality and motor coordination can be established.

The present work tested the usefulness of combined bilateral palmar skin potential and nostril dominance measures as indices of relative hemispheric activation. These measures are easy to obtain and, when used in tandem, may provide inexpensive and quick indices of relative hemispheric activation for the researcher interested in laterality, but with limited resources. Bilateral electrodermal palmar measurements were made and synchronous nostril dominance was recorded for one experienced subject (the author). A total of 760 individual skin-resistance measures were taken for a period of 26 days from 7 a.m. to midnight. Higher right-hand conductance measures were recorded than the left-hand measures. Electrodermal palmar asymmetry was confirmed during the right-nostril condition, whereas more symmetrical palmar recordings were obtained during the left-nostril condition.

Laterality Quotients for 80 American Indian college students were less right-biased than those for 80 Caucasian college students on the Edinburgh Handedness Inventory. Oldfield's 1971 empirically derived deciles for the Edinburgh Handedness Inventory were used to assign decile levels to the data. Deciles were then used to assign data to one of three proposed handedness phenotype classifications. Pheno-type classifications were based on Annett's 1985 proposed distribution for a single gene theorized to underlie human handedness. Chi-squared goodness-of-fit analysis showed that the data for Caucasian college students did not differ significantly from what would be anticipated by Annett's model, but American Indians differed significantly. Results provide empirical support for the hypothesis that frequency distributions for Annett's hypothesized right-shift gene may differ across racial groups.

Developmental disorders of reading and spelling have long been associated with increased left- and mixed-handedness but the evidence has been controversial. The right shift (RS) theory of handedness and cerebral dominance, developed by Annett from 1972 onward, offers resolutions to several puzzles about laterality in the so-called dyslexias. This review of findings in the light of the theory shows that “phonological” dyslexies are less likely to be right-handed, while “surface” or “dyseidetic” dyslexies are more likely to be right-handed than the general population.

Subjects classified by scores on the Preference Questionnaire as preferring either a left- or a right-hemisphericity style were asked to read a one-page passage and to circle each letter t they encountered as they read the passage. There were no statistically significant differences in letter detection between the 58 right- and the 64 left-style scorers. However, contrary to previous findings, the 73 women detected significantly more ts, including unsounded ts, than the 55 men. Our results suggest that hemisphericity style is not an important factor in letter detection.

Cross-sectional development and consistency of four lateral preference behaviors (hand, foot, ear, eye) in 79 preschool and 131 primary school children were studied. Although predominant right-sidedness is manifested in the limbs and sensory organs, only handedness showed a significant increase over the age range studied (3 yr. to 9 yr., 11 mo.). Approximately 85% of children in preschool and 87% in primary school showed lateral consistency in the upper and lower extremities. The concordance between other sidedness behaviors reflected only chance associations in both samples. The results indicate that lateral preference behaviors in children are not unidimensional.

The accuracy for both a color-naming and a color-matching task as a function of visual field and sex was investigated in preschool children. Subjects were 17 boys and 17 girls ranging in age from 4.4 to 5.6 yr. Each subject was tested on both tasks, for which the target stimuli were presented tachistoscopically. Accuracy measures for each task were obtained separately for both left and right visual fields. A two-factor (sex x visual field) analysis of variance with repeated measures on the visual-field factor showed a significant difference between the sexes on the color-naming task only. No significant difference between visual fields was found for either task. However, significant interactions between sex and visual field for both the color-naming and color-matching tasks were obtained, t tests for simple main effects showed a significant right visual-field advantage for girls in naming colors. Conversely, a significant left visual-field advantage for color-matching was found for boys. Also, on the color-matching task, significant sex differences were found for both visual fields when compared separately. Boys were more accurate for left and girls more accurate for right visual field. Boys performed in a more strongly lateralized fashion on the color-matching task than did the girls, supporting the notion of greater lateralization among males.

Since little is known concerning the cortical and cognitive effects resulting from the study of a tonal, logographic language which is read from top to bottom and in a right-to-left direction, neuropsychological and intellectual measures on 51 bilingual and 41 monolingual Chinese-American children aged 9 to 12 years were compared. Multivariate statistical analyses yielded significant group differences. As predicted, the over-all mean IQ of bilinguals was higher than that of monolinguals. Other than coding skills, expected superior performance of bilinguals on right-hemisphere or bilaterally sensitive measures was not found; rather, the left-dominant sequential abilities of bilinguals surpassed those of their monolingual peers. English fluency of the two groups was equivalent and monolingual youngsters obtained higher scores on two of five academic achievement tests than bilinguals. The effects of Chinese language instruction among Chinese-American children are discussed in relation to the distinguished educational accomplishments of Asian Americans.

were assessed in 36 normal subjects using a tactile line-bisection task described in 1980 by Bowers and Heilman. An interaction between hand of performance and spatial position indicated that both hemispace and anatomical pathways determine laterality effects. Neither the left-hand superiority nor the leftward error in the midline condition by both hands found in an earlier study could be observed here. Only righthanders were influenced by starting condition, which in this setting acted as a spatial cue. Finally, some subjects used nonspatial strategies, a confounding factor that needs evaluation in further studies. Visual line-bisection is commonly used as a simple bedside test of unilateral neglect (Bisiach, Bulgarelli, Sterzi, & Vallar, 1983). Particularly right brain-damaged patients with neglect transect lines to the right of the geometric midpoint. Several studies have examined visual line-bisection in normal subjects (Bisiach, et al., 1983; Bradshaw, Nettleton, Nathan, & Wilson, 1985; Nichelli, Rinaldi, & Cubelli, 1989; Scarisbrick, Tweedy, & Kulanski, 1987).

This article describes a contact-lens method to sustain asymmetry in visual deprivation and the use of this method to test the general hypothesis that asymmetry in input deprivation can shift activation balance in the integrated brain, differentially influencing lateral hemispheric function. Effects of asymmetrical visual deprivation were as predicted on lateral asymmetry of EEG theta, producing more theta over the deprived hemisphere. Cross-modal influence of such visual deprivation was found in the perception of pleasantness of odors. An interaction was found between side of visual deprivation and performance on verbal reasoning and spatial orientation tasks. A line-bisection test of visual attention was not sensitive to the effects. Fatigue as rated on the Profile of Mood States was greatest when the left hemisphere was deprived.

240 university students were given The Cognitive Laterality Battery as well as a questionnaire, the answers to which were used to identify those who had experienced an “Old Hag Attack.” This refers to a hypnagogic sleep disorder in which there is paralysis and, quite often, terrifying hallucinations. Those suffering from this disorder showed a statistically significantly different profile of scores from normal subjects on The Cognitive Laterality Battery. The implications of this finding for existing theories concerning “Old Hag Attacks” are discussed.

The fallacy of the argument for reduced longevity in left-handers depends on the use of the writing hand in the assessment of the present generation of elderly people, when writing was not used as a criterion in the early years of the century. A ‘thought’ experiment demonstrates that a sample of left-handers is Likely to be younger than a sample of right-handers alive in the population and this would be true also of the recently deceased.

This paper reports sex differences in cognitive task performance that emerged when 39 Australian university undergraduates (19 men, 20 women) were asked to solve verbal (lexical) and visual-spatial cognitive matching tasks which varied in difficulty and visual field of presentation. Sex significantly interacted with task type, task difficulty, laterality, and changes in performance across trials. The results revealed that the significant individual-differences' variable of sex does not always emerge as a significant main effect, but instead in terms of significant interactions with other variables manipulated experimentally. Our results show that sex differences must be taken into account when conducting experiments into human cognitive-task performance.

In 1990 Cheatham suggested there might be a right-ear advantage for the perception of speech and music for right-handed individuals, which confirms Kinsbourne's observation of a general right-ear advantage. These findings, however, contrast with Segalowitz and Plantery's work that supports attentional bias in lateralized processing of these stimuli. The attentional bias model has also been criticized by Bryden on the basis of its circularity. At present there has not been sufficient evidence to settle this debate empirically. The author suggests that the controversy may best be resolved by disentangling the folklore surrounding spatial localization and auditory lateralization to reexamine this field in light of recent empirical findings by Bryden and by Porac, Coren, and Duncan, who inferred an inherent rightward bias to many kinds of stimulation, including auditory, in right-handed individuals. The present focus is that Cheatham's 1990 data lend themselves more readily to the rightward bias that occurs in right-handed subjects and not to previous structural or attentional models.

To examine hand differences in the sensory feeling of texture, 35 subjects made sensory evaluations with the left and the right hands to a tactile stimulus (sponge rubber) and also marked on a 5-point Likert scale 50 adjectives which represented various tactual feelings. Factor analyses, applied to the data of 35 subjects, showed that the left hand related more to a keen and sharp dimension while the right hand related more to a mild and soft dimension of the tactile stimulus. Possible relations of these hand differences in sensitivity to hemisphere functioning were discussed.

The Purdue Pegboard and Moving Beans with Tweezers test have been used in the rehabilitation of persons with nervous system disorders; however, these two tests differ in their methodology. In the latter test, the testee picks up items with chopsticks or tweezers, but in the former test, the testee grasps items directly with the fingers of one hand. Use experience of a tool may strongly influence performance. The present study examined the use of chopsticks in daily life on performance of the two tests of finger dexterity by two groups of 20 youths who habitually used chopsticks to eat and 20 who did not. Three 30-sec. trials with the dominant and nondominant hands were given. Analysis of variance gave a main effect for number of beans moved between the two groups, hand (nondominant vs dominant), and trials. Significantly more beans were moved by the group with prior chopsticks use than the nonusers by the dominant hand than the nondominant hand, and on Trials 2 and 3 than Trial 1. For the Purdue Pegboard, the only significant difference for trials showed fewer pegs moved on Trial 1 than Trial 3. In conclusion, the groups who habitually used chopsticks performed better on the Moving Beans with Tweezers test than the group without such experience. Also, the marked laterality and practice effects for chopstick users was not observed on the Purdue Pegboard.

This article describes the use of tympanic thermometry in investigations of hemispheric specialization. Subjects were asked to perform tasks known to be performed preferentially by the right or left hemisphere while fluctuations in tympanic temperature (reflecting changes in hemispheric metabolic activity) were recorded from thermal sensors placed in their outer ear canals. The analyses show that subjects who evince relatively higher elevations in metabolic activity (as measured through tympanic thermometry) in the hemisphere specialized for the task obtain better performance scores than those who show a reversed bias.

This study was done to assess whether black and Caucasian students differ in hemispheric skills and whether such preference is related to reading achievement. Subjects were 111 fourth- and fifth-graders from a small rural school district in southwestern Michigan. For this group there was no significant difference in inferred hemisphericity on the Cognitive Laterality Battery with respect to race or sex, neither was hemisphericity related to reading achievement on the Iowa Tests of Basic Skills. However, individual subtests of the Cognitive Laterality Battery were significantly related to reading comprehension on the Iowa achievement tests.

Programs for the computer analysis and interpretation of neuropsychological test data have been developed in recent years. In this paper, a new computer program, with initial validation data, is presented. Diagnostic hit rate for brain damage was 80% (52 of 65). For the extent of brain damage the hit rate was 60% (12 of 20). When laterality was considered, the hit rate was 71% (10 of 14). These results are comparable with computer programs for data from the Halstead-Reitan Neuropsychology Test Battery.

This study was aimed at testing a new approach for examination of functional laterality based on hemispheric specialization. The subjects had to perform verbal (words/nonwords) and nonverbal (similar/different patterns) discrimination. The separation of the two hemispheres during information processing was realized by requiring a simultaneous response of both index fingers. The obtained over-all reaction times (RT) were faster for verbal than for pattern tasks. Considering the RTs for solely the particular, faster response of one or the other index finger, the right index finger turned out to be faster on verbal tasks whereas the left one dominated on pattern tasks. According to the hypothesis that the faster hand indicates the more active (contralateral) hemisphere, it can be assumed that words are responded to more quickly when processed in the left hemisphere. On the other hand, patterns are responded to more quickly when the right hemisphere is active. These results suggest that each hemisphere may be capable of processing verbal and nonverbal material; the speed of information processing, however, is faster in the more adept one.

The objective was to determine whether gait is symmetric in healthy children 6–7 years of age and to assess the effects of laterality and the anatomical zone of the foot. 46 children were subjected to gait symmetry analysis in which the plantar and lateral pressures associated with kicking a ball, static balance, and dynamic support were measured. There were no significant differences in the average pressure exerted by the right and left feet based on the laterality of the child. Independent of each laterality test, a greater pressure on the right rearfoot was observed compared to the left rearfoot and on the left midfoot and forefoot compared to the right.

In the past two decades, laterality in sports has become clearly established. In particular, the concept of motoric dominance in sports has been a fertile area for laterality research. The literature is consistent with the view that in certain sporting skills, sporting competitors with specific motoric-dominance patterns enjoy an advantage over other competitors and are overrepresented in some sports. Two theoretical interpretations have been offered to explain this imbalance of motoric-dominance distribution among sporting individuals: hypotheses of “innate superiority” and “strategic advantage.” This paper presents an overview the two hypotheses, along with relevant work so far reported and identifies directions for further empirical research. The theoretical and practical implications of research on laterality in human motor performance are discussed.

Aydin and colleagues reported a reversal of physiological ‘right-ear advantage' in a group of right-handed patients with schizophrenia, using an auditory acuity test. In schizophrenia, auditory hallucinations may appear to be spatially located inside or outside the patient's head. Here we show, using virtual acoustic space techniques, that normal right-handed subjects have a right-ear advantage for correctly locating the ‘source' of hallucination-like voices as from either inside or outside the head. We propose a model for understanding lateralised, external hallucinations in schizophrenia based upon reversal of normal cortical asymmetry for auditory spatial processing.

The intimate relation between the sensory and motor functions of the hands during object manipulation and exploratory touch, the well-known improvement in object handling and constructive performance in ontogenesis and the emergent laterality thereof, assume changes in morphognostic capabilities in children. In this study we tried to corroborate the hypothesis of Mesker that mature and lateralized finger-thumb opposition is preceded by a stage of two-sided manual form agnosia in preschool children, followed by acquisition of morphognosis of the fingers and, finally, the thumbs. This study examined the development of gnostic hand function in 290 children from 3 to 11 years of age who drew the outlines of a meaningless wooden object passively felt with each hand without visual control. Analysis showed a clear ontogenetic change across the two age groups of increasing morphognostic function: 48% of the 6-yr.-olds drew correctly what the fingers of both left and right hands had perceived (thumbs, 14%). Of the 11-yr.-olds 91% and 61% performed perfectly with the right and left hands, respectively. The fingers preceded the thumbs in reproduction by most children, and the correct reproduction by the left thumb precedes that of the right thumb. The ontogenesis of bimanual sensorimotor functioning is discussed in the light of cortical and callosal development.

Correlations of various laterally scores for 202 persons with cognitive test scores in the seventies of mental retardation are presented.

A rightward bias to all forms of sidedness seems to be particularly human and perhaps characteristic of every human society. However, this phenomenon has been studied mainly in relation to lateralization of handedness and language. This study investigated the consistency of right- and nonright-handed individuals in preferring the same side for foot, eye, and ear using Coren's Lateral Preference Inventory. The sample of 194 students, 91 boys and 103 girls, ranging in age from 11.5–14.5 years ( M age 13.2 yr.) was recruited from public junior high schools in a rural area in Greece on the island of Rhodes. Despite the dominance of the right side observed in handedness, footedness, eyedness, and earedness, this tendency was not equally strong in all four indexes of lateral preference, with handedness showing comparatively the strongest tendency and earedness showing comparatively the weakest tendency. Moreover, the strength of preference for the same side for foot, eye, and ear was significantly weaker in nonright-handed individuals compared to right-handed individuals. These results agree with the hypothesis that nonright-handers may have reduced rather than reversed asymmetry.

On the basis of operationally defined handedness data from 1,348 subjects of both sexes and of ages 10 to 15 years, laterality was compared with prehistorical data of handprints found in caves. It was hypothesized that the greater production of left handprints found in caves in comparison with current data should be ascribed to a nonestablished deviation of lefthanders towards righthandedness as environmental pressures in the distant past were lower.