Degree Of Hand Preference Research Articles

Hand preference and Mathematical Learning Difficulties: New data from Greece, the United Kingdom, and Germany and two meta-analyses of the literature

ABSTRACT Increased rates of atypical handedness are observed in neurotypical individuals who are low-performing in mathematical tasks as well as in individuals with special educational needs, such as dyslexia. This is the first investigation of handedness in individuals with Mathematical Learning Difficulties (MLD). We report three new studies (N = 134; N = 1,893; N = 153) and two sets of meta-analyses (22 studies; N = 3,667). No difference in atypical hand preference between MLD and Typically Achieving (TA) individuals was found when handedness was assessed with self-report questionnaires, but weak evidence of a difference was found when writing hand was the handedness criterion in Study 1 (p = .049). Similarly, when combining data meta-analytically, no hand preference differences were detected. We suggest that: (i) potential handedness effects require larger samples, (ii) direction of hand preference is not a sensitive enough measure of handedness in this context, or that (iii) increased rates of atypical hand preference are not associated with MLD. The latter scenario would suggest that handedness is specifically linked to language-related conditions rather than conditions related to cognitive abilities at large. Future studies need to consider hand skill and degree of hand preference in MLD.

Handedness in monkeys reflects hemispheric specialization within the central sulcus. An in vivo MRI study in right- and left-handed olive baboons

Handedness, one of the most prominent expressions of laterality, has been historically considered unique to human. This noteworthy feature relates to contralateral inter-hemispheric asymmetries in the motor hand area following the mid-portion of the central sulcus. However, within an evolutionary approach, it remains debatable whether hand preferences in nonhuman primates are associated with similar patterns of hemispheric specialization. In the present study conducted in Old world monkeys, we investigate anatomical asymmetries of the central sulcus in a sample of 86 olive baboons (Papio anubis) from in vivo T1 anatomical magnetic resonance images (MRI). Out of this sample, 35 individuals were classified as right-handed and 28 as left-handed according to their hand use responses elicited by a bimanual coordinated tube task. Here we report that the direction and degree of hand preference (left or right), as measured by this manual task, relates to and correlates with contralateral hemispheric sulcus depth asymmetry, within a mid-portion of the central sulcus. This neuroanatomical manifestation of handedness in baboons located in a region, which may correspond to the motor hand area, questions the phylogenetic origins of human handedness that may date back to their common ancestor, 25–40 millions years ago.

How should we test infant handedness?

ABSTRACTAs soon as infants grasp objects, they exhibit some degree of hand preference. Although all studies agree that the number of non-lateralized infants remains high during the first months of life, there is no consensus on the percentage of right- and left-handed infants. Reasons might be the different formulae used to calculate an handedness index, the basis on which handedness categories are distinguished, and the number of trials per session. In this study we aimed to provide a valid method of testing handedness, reliable without being lengthy so as to combine it with other evaluations. We tested 46 infants at 9 and 11 months by giving them 34 trials. We compared the results using 2 of the most used formulae, including the bimanual grasps or not, and considering the first 5, 10, 15, 20, 26, 31, or all 34 trials. The results show that different formulae do not give significantly different results as long as bimanual grasps are included. The number of trials is important: 15 trials are necessary for the reliability of the classification into handedness categories. Giving more trials does not provide substantial additional information.

Correlation of handedness with hand anthropometric measurements in Haryanvi Brahmins

IntroductionAnthropometric studies have revealed that in comparison of the two halves of the human body, the values belonging to the right half are different than those of left half. This is due to effect of directionality and degree of handed preference, a functional property of hand, on anthropometric measurement of hand in healthy individual. In the present study, the aim is to provide authentic database on hand anthropometric measurements in Haryanvi Brahmins and to study its co-relation with handedness. MethodsThe present study was conducted on 300 Haryanvi Brahmins (150 of either sex of age 18 years) and above. Three hand measurements: hand length, hand breadth and shape index were taken with a digital sliding caliper. Handedness was determined according to Edinburgh Inventory which evaluates the direction and degree of hand preference. ResultsThe mean values of hand parameters were significantly different between males and females, right handers and left handers. Hand breadth and shape index were found to be greater in the right hand in strong and weak right hand preference groups in Haryanvi Brahmins. DiscussionLeft hand preference groups displayed irregular and heterogenous characteristics with regard to hand parameters. When correlation between laterality score and hand parameters was examined no specific hand measurements were found to be indicators of hand preference in Haryanvi Brahmins.

On the relationship between degree of hand-preference and degree of language lateralization

Language lateralization and hand-preference show inter-individual variation in the degree of lateralization to the left- or right, but their relation is not fully understood. Disentangling this relation could aid elucidating the mechanisms underlying these traits. The relation between degree of language lateralization and degree of hand-preference was investigated in extended pedigrees with multi-generational left-handedness (n=310). Language lateralization was measured with functional Transcranial Doppler, hand-preference with the Edinburgh Handedness Inventory. Degree of hand-preference did not mirror degree of language lateralization. Instead, the prevalence of right-hemispheric and bilateral language lateralization rises with increasing strength of left-handedness. Degree of hand-preference does not predict degree of language lateralization, thus refuting genetic models in which one mechanism defines both hand-preference and language lateralization. Instead, our findings suggest a model in which increasing strength of left-handedness is associated with increased variation in directionality of cerebral dominance.

Influences of lateral preference and personality on behaviour towards a manual sorting task

Differences in task behaviour between left- and right-handers and left- and right-eared individuals have been reported (e.g. Jackson, 2008; Wright, Hardie, & Rodway, 2004) with left-handers taking longer to begin a task and right-eared individuals having a more disinhibited approach. Personality measurements are also important when examining approach behaviour. Jackson (2008) reported that those with higher neuroticism levels and a right-ear preference react faster to tasks. The current study investigated the effects of lateral preference and personality on behaviour towards a manual sorting task. Eighty-five participants completed laterality and personality scales and a card-sorting task. Degree of hand preference was found to influence behaviour towards the task with strong left-handers taking longer to begin. Those with a left congruent lateral preference (left-hand, left-ear) took significantly longer to begin the task than those with a right congruent preference. Neither neuroticism nor extraversion influenced task approach. We concluded that hand preference, and more specifically a strong left-hand preference is a good predictor of a longer initiation time on a manual task. Ear preference on its own does not predict initiation time.

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The principal objective of this work is to investigate the relationship between lateral functions of the brain and morphology of the hands, eyes and feet. The study was carried out with 233 volunteers within the age range of 18 to 27 years. Out of the total number of participants, 208 (94%) of them were right-handed and the remaining 13 (6%) were left-handed. The participants were divided into two groups and assessed by twenty items. First ten (Q1) and second ten (Q2) items were taken from Edinburg Handedness Inventory (EHI) and the Yetkin Laterality Questionnaire (YLQ). The degree of hand preference was determined by Geshwind scores (GSs). Q1 was used to assess only hand preference, while Q2 was used for laterality of the one side of the body from eye to foot. Statistically, non-significant (p>0.05) difference (3%) was observed between the Q1 (63%) and Q2 (60%). Breadths and lengths of the hands were measured across 2 to 5 metacarpal region, from peripheral line on the wrist to middle fingertip. While the difference between the breadths of right and left hand was significant (p<0.05), the difference between the lengths of hand was non-significant (p> 0.05). The breadths and lengths of the feet were also measured in the same way. Subjects performed three different voluntary motor activities, such as basketing (throwing basketball: BT), aiming at (targeting: TT) and peg moving tasks (PMT) with their right and left hands in turn to perform the tasks, respectively. In the BT and TT tasks, the difference between the right and left hand performance was non-significant (p>0.05), though, the difference was significant (p<0.05) for PMT. The findings suggest that both the proximity of the hand preferences and the difference of the hand sizes could be the results of the hemispheric dominance in the brain. In this study, it was found that there was a significant difference for left- versus right- hand breadths and left and right-hand motor performances which is shown to be both morphological and functional in asymmetry.   Key words: Laterality, hand preference, basketing, targeting, peg-moving, motor performances, brain asymmetry, human.

Hand preference for pointing and language development in toddlers

The aim of this study was to investigate the relationship between hand preference for communicative gestures and language during development. Hand preference for pointing gestures and level of language were assessed in 46 toddlers between 12 and 30 months of age. Results showed a right-hand preference for pointing and the use of a developmental quotient (DQ) for language revealed a significant correlation between the degree of hand preference and DQ for language in children with a quotient above 100. Thus, these children were more right-handed for pointing gestures as DQ increased. These results highlight the close association between the development of hand preference for pointing and the speed of language development, suggesting a new direction for studies of language-gesture links in toddlers.

Can an observational method of assessing hand preference be used to predict language lateralisation?

The current study investigated (a) whether or not the WatHand Cabinet Test (WHCT, Bryden, Roy, & Spence, 2007) could be used as accurately as the Waterloo Handedness Questionnaire (WHQ) to classify individuals into language lateralisation groups based on their hand preference, and (b) the relationship between direction and degree of hand preference and language lateralisation. A total of 142 participants (82 right-handers and 60 left-handers) completed the WHQ and the WHCT, and performed a fused-words dichotic listening test. Findings indicated that the WHCT was robust alternative to the WHQ in providing a measure of hand preference as there was a high correlation between the WHCT and the WHQ, and individuals were divided into similar language lateralisation groups when using either the WHCT or the WHQ as the classifying variable. More specifically, there existed a predictable pattern of language lateralisation into which members of different handedness groups fell. The same pattern exists whether handedness is defined using subjective questionnaires or more objective observational measures of hand preference.

Hand preferences in human adults: Non-communicative actions versus communicative gestures

Hand preferences for pointing gestures and bimanual manipulative activities were investigated in 127 adult participants. Pointing gestures were produced in two different conditions: a speech condition, in which the gestures were accompanied by speech, and a silent condition. Although the classification of participants as left- or right-handers, or ambidextrous, was consistent across the manipulation and pointing tasks for 85% of participants, results showed only moderate correlations between handedness scores for bimanual manipulation and pointing gestures. Moreover, results did not reveal any difference in the degree of hand preference between pointing gestures produced along with speech and gestures produced on their own. The implications of these findings are discussed in relation to the lateralization of non-communicative manual actions, communicative gestures and speech.

Manual asymmetry in a complex coincidence-anticipation task: Handedness and gender effects

This study investigated the effects of handedness and gender on manual asymmetry in the performance of a complex coincidence-anticipation task. Left-handed (N=63) and right-handed (N=93) undergraduate students (78 males, 78 females) were required to press six buttons sequentially in conjunction with visual stimulation provided by a coincidence-anticipation apparatus. Participants were further separated into subgroups based on the degree of hand preference. Timing accuracy (AE, CE, VE) and timing response (IT, MT, AT) were analysed. Results showed that, concerning accuracy, (i) strong left-handers were more accurate than the other groups; (ii) performance with the preferred hand was superior to that of the non-preferred hand; and (iii) males outperformed females. Concerning timing response, (i) the preferred hand was faster than the non-preferred hand for movement time and (ii) males were faster in initiating the movement than females. These findings indicate that coincidence-anticipation competence appears to be influenced by hand preference, performing hand, and gender. In addition, findings are discussed in the framework of the hemispheric functional lateralisation for the planning and organisation of movement execution.

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preference and performance abilities, a cross-sectional sample of 548 children (ages 3–18) and adults (over 19) completed the Waterloo Handedness Questionnaire, the WatHand Cabinet Test (an observational test of hand preference), and the Annett pegboard. Findings revealed that while the direction of hand preference does not change significantly with age, the degree of hand preference does, such that younger children exhibit weaker hand preference than older children and adults. This pattern of hand preference was much more evident for lefthanded individuals, where consistent hand preference was not seen until 8 years of age. Similarly, performance differences between the hands did not emerge for left-handers until later childhood, while in comparison large performance differences were seen for right-handers at all ages. The implications for the development of handedness will be discussed.

Home-Recorded Sleep Architecture as a Function of Handedness II

Examination of individual differences in sleep architecture may help elucidate the mechanisms involved in sleep-related pathologies and cerebral processes involved in sleep. We (Propper et al., Brain Cogn. 2004;54:186-197) previously reported that degree or strength (i.e., inconsistent vs. consistent) of hand preference was more important than direction (i.e., left vs. right) of hand preference in examining sleep architecture-hand preference relationships. However, that study confounded direction and degree of hand preference; only 1 consistently left-handed individual was included in the consistently handed group. Here, we describe a comparison of the sleep of consistently left- versus consistently right-handed individuals. The basic pattern of results here and in previous work suggests that individual differences in sleep architecture are influenced by both degree and direction of handedness. Handedness differences in sleep architecture may reflect individual differences in cerebral organization on one hand and sleep stage mediated differences in cerebral interaction on the other.

Do Environmental and Hereditary Factors Affect the Psychophysiology and Left-Right Shift in Left-Handers?

The principal objective of this study was to investigate the reality of sinistrality in left-handed subjects. The subjects were assessed by a 20-item questionnaire with two groups taken from Oldfield's and Yetkin questionnaires. The relation of different effects on left-hand preference was studied in men and women considering familial information and writing hand. The degree of hand preference was determined by Geshwind scores (GSs). The GS degrees of hand preferences were divided into weak and strong left-hand ranging from -20% to - 100%.After assessing the GSs we asked the subjects to answer 22 questions with different aims. which were especially written for only left-handers. Some of them were based on familial sinistrality and hereditary relation to left-handers. The others concerned hand, foot, eye, shoulder, and ear preferences; the psychology of left-handedness; the knowledge concerned with left-handedness; the success, ability, and interest education and skill, and morphological differences in hand and foot sizes.In the present study, it was found that the subjects have had at least one left-handed person in their family or among their relatives. Some subjects had shifted their left hand preference in favor of their right hands. Nevertheless, the left-handers have been found as a presence with their own peculiarities.

Motor Control of the Hands: The Effect of Familial Sinistrality

Left-and right-handed subjects, selected on the basis of degree of hand preference and for the presence or absence of familial sinistrality, responded to monaurally presented tonal stimuli (440 Hz note played on four different instruments) using their right and left hands on separate occasions. It was found that in both the strong left-handers and the inconsistent strong right-handers, motor control of the hands was related to familial sinistrality (FS). Specifically, strong left-handers and inconsistent strong right-handers with FS have a difference in the motor control of the hands in the left hemisphere, with a left hemisphere-left hand advantage. Strong left-handers and inconsistent strong righthanders with no FS have a difference in the motor control of the hands in the right hemisphere, with a right hemisphere-left hand advantage.

Spatial Task Demands Affect the Extent of Manual Asymmetries

The degree of hand preference and the magnitude of hand differences in performance are thought to relate to skill level. The purpose of the experiments discussed here was to examine the effect of skill as reflected in the spatial precision demands of a movement, on the extent of manual asymmetries. Experiment 1 utilised the Annett pegboard, and manipulated spatial precision by varying peg diameter. The second experiment utilised the Grooved pegboard, and manipulated spatial precision by altering the size of the target hole. Analyses revealed that movement time increased as a function of the increased spatial precision demands. Although the preferred hand was always faster, the magnitude of this advantage was only affected in Experiment 2, in which the manipulation of spatial precision was maximal. The implications of these findings for the skill interpretation of handedness are discussed.

282 The effect of sex and masculinity on the degree of hand preference; association with familial sinistrality

282 The effect of sex and masculinity on the degree of hand preference; association with familial sinistrality

Evolution of Degree and Direction of Hand Preference in Children: Methodological and Theoretical Issues

This paper presents some methodological and theoretical issues based on a longitudinal study, performed in schools, on hand preference of 256 children, initially aged 3–6 years. Three phenomena are observed: (1) the well-known asymmetry of the hand preference distribution, which probably depends on biological factors; (2) a weak “towards the right” tendency with increasing age, which could be explained by environmental factors; and (3) a strong increase in the degree of hand preference with age which could be a consequence of the subject's own activity. Handedness is considered here as a possibly interesting model to delineate the respective role of biological, environmental, psychological, and pathological factors involved in a simple human behaviour.

Tracheal growth in congenital tracheal stenosis: Manson D.; Filler R.; Gordon R.Pediatr. Radiol. (CAN) (1996) 26/6 (427–430)

Differences in task behaviour between left- and right-handers and left- and right-eared individuals have been reported (e.g. Jackson, 2008, Wright et al., 2004) with left-handers taking longer to begin a task and right-eared individuals having a more disinhibited approach. Personality measurements are also important when examining approach behaviour. Jackson (2008) reported that those with higher neuroticism levels and a right-ear preference react faster to tasks. The current study investigated the effects of lateral preference and personality on behaviour towards a manual sorting task. Eighty-five participants completed laterality and personality scales and a card-sorting task. Degree of hand preference was found to influence behaviour towards the task with strong left-handers taking longer to begin. Those with a left congruent lateral preference (left-hand, left-ear) took significantly longer to begin the task than those with a right congruent preference. Neither neuroticism nor extraversion influenced task approach. We concluded that hand preference, and more specifically a strong left-hand preference is a good predictor of a longer initiation time on a manual task. Ear preference on its own does not predict initiation time.

A study of correlates of hand preferences in squirrel monkeys (Saimiri sciureus)

The purpose of this study was to test the influence of sex, age, social rank, matriline membership, posture, and visual and tactual motor control on manual preferences inSaimiri sciureus. A well-established social group of 12 squirrel monkeys, aged 2 to 14 yrs and consisting of two matrilines with social rank known for each animal, was presented with four different food-reaching tasks and assessed for hand preferences with a minimum of 100 reaches per animal. Frequency of occurrence of hand preferences at the group level and degree of hand preferences at the individual level depended on posture and on whether the reaching act took place under visual or tactual guidance. Sex, age, social rank, and matriline membership were not found to determine frequency of occurrence, direction or degree of hand preferences with the exception of one task in which a significant negative correlation between the degree of hand preference and age was found. Nine out of 12 monkeys showed task-dependent changes in the hand they used preferentially while only three animals preferred the same hand in all four tasks. Significant preferences for the use of right or left hand on a given task were distributed almost equally between individuals. Thus, the results of this study suggest task-specific demands like posture and/or whether reaching was visually or tactually guided to be the major correlates of hand preferences in food-reaching tasks in squirrel monkeys.