Deriving estimates of contralateral footedness from prevalence rates in samples of Brazilian and non-Brazilian right- and left-handers

Inventories of Human Lateral Preference: A Systematic Review

There are a variety of inventories available to evaluate human lateral preference, but no previous review has systematically analyzed and compared them. We conducted a systematic literature review to identify these inventories and describe their characteristics (e.g., dimensions, scales, tasks, psychometric properties). We included 26 articles, each presenting a different inventory to assess lateral preference, published between 1900 and 2022, selected from the following databases: PubMed, SportDiscus, APA PsycNET, and Web of Science. These inventories analyzed tasks performed in everyday life (domestic, work-related, sports, and leisure/recreation activities), covering hand, foot, hearing, visual and other non-usual lateral preference dimensions, such as trunk and head. Most inventories classified individuals based on the direction (left, indifferent or right preference) and degree (consistent or moderate) of laterality. However, many of the reviewed inventories lack established psychometric verification in their original publication, such as validity, reliability, responsiveness, and practical applicability. Inventories also presented tasks that may be specific to a given cultural setting, limiting their application across different countries. Based on these findings, we provide a comprehensive guide for researchers to select a lateral preference assessment tool, but also advocate for a new inventory with a broader approach, containing more than one dimension of lateral preference (i.e., not only handedness) and tasks that are common to different cultures to enhance practical applicability worldwide.

RELATIONSHIPS BETWEEN HAND AND FOOT PREFERENCES

The aim of this study was to evaluate the relations between hand and foot preferences in male and female individuals (343 male, 290 female) aged between 18-42 years (22.11 +/- 2.07). Of the right-handed men, 75.5% preferred the right foot, 7.1% the left foot, and 17.4% both feet. Of ambidextrous men, 44.0% preferred the right foot, 28.0% the left foot, and 28.0% both feet. Of left-handed men, 32.3% preferred the right foot, 56.9% the left foot, and 10.8% both feet. The differences between these percentages were found to be statistically significant. Of the right-handed women, 89.9% preferred the right foot, left foot 1.2%, both feet 8.9%, whereas 50.0% preferred the right foot, 12.5% the left foot, and 37.5% both feet in the ambidextrous women. In the left-handed women, 8.8% preferred the right foot, 79.4% the left foot, and 11.8% both feet. The differences between these percentages were found to be statistically significant. The results suggested that the cultural differences among the difference study groups may be the reason for the inconsistencies with regard to hand and foot preferences. Moreover, the results may bring insight into the foot preference in relation to hand preference in the Turkish population.

Increased Frequency of Left-Handedness in Patients with Unilateral Coronal Synostosis

Objective:

Left-handedness reportedly has been more common in persons with neurological afflictions (e.g., stroke) and malformations (e.g., cleft lip with or without cleft palate) that demonstrate marked unilateral involvement. Coronal synostosis is also more frequently unilateral, affecting the right side more commonly than the left. We sought to compare left-handedness in patients with unilateral coronal synostosis versus healthy controls.

Subjects:

All patients aged 3 years or older with nonsyndromic unilateral coronal synostosis and healthy controls recruited by pediatricians blinded to the study.

Main Outcome Measures:

Prospective data obtained for all participants included age, gender, and handedness. In patients with unilateral coronal synostosis, the side of synostosis and age at surgery were documented. Left-handedness in the study and control groups was compared using chi-square analysis. Left-handedness also was analyzed in the study group according to side of fusion.

Results:

Eighty-six patients with nonsyndromic unilateral coronal synostosis comprised the study group; there were 96 controls. The mean ages of the study (8.8 years) and control groups (9.8 years) were not statistically different (p > .05). There were more girls in the study group (67%) than in the control group (56%), but this difference was not statistically significant (p > .05). Left-handedness was documented in 30.2% of the study group and 11.4% of the control group (p < .005). Left-handedness was twice as common in patients with left versus right unilateral coronal synostosis (44.4% versus 20.4%; p < .05).

Conclusions:

Left-handedness is nearly three times more common in patients with unilateral coronal synostosis than in controls and four times more likely in patients with left-sided fusion.

Increased prevalence of left-handedness in hemifacial microsomia

Ten percent of people are left handed, but a higher frequency has been associated with certain craniofacial malformations, such as cleft lip and unilateral coronal synostosis. The purpose of this study was to determine the frequency of left-handedness in patients with hemifacial microsomia (HFM). Patients with HFM were identified in our craniofacial database. Normal controls were recruited by local pediatricians. Data gathered included age, sex, and handedness (determined by writing and/or drawing); the orbit, mandible, ear, nerve, and soft tissue (OMENS)-plus score and side of involvement were tabulated for patients with HFM. Hand preference was compared between the groups using chi analysis; possible correlations were analyzed between handedness and age, sex, the OMENS score, extracraniofacial findings, and side of involvement. One hundred seventy-eight patients with HFM were identified; 92 (51%) were excluded. Of the 86 included, 48% were boys (n = 47) and the mean age at inquiry was 13.5 years. Predominant side of involvement was right in 49% (n = 42) and left in 38% (n = 33). Eleven patients (13%) had severe involvement of both sides. Expanded-spectrum HFM was documented in 41% of patients. Ninety-six children were in the control group; 44% were boys (n = 42), and the mean age was 10 years. The difference in age between the groups was significant (P < 0.05), but sex differences were not. Patients with HFM were more likely to be left handed for writing compared with the control group (26% vs. 11%; P < 0.05). The frequency was higher, 36%, in those with bilateral involvement (P > 0.05). There was no correlation with predominant side or OMENS score. This study confirms that this disorder affects cerebral lateralization.

Zusammenhänge zwischen Händigkeit und motorischen und kognitiven Leistungen im Kindesalter

Zusammenfassung. In einer Längsschnittstudie wurden die Entwicklung der Händigkeit bei Kindergartenkindern (153 Jungen und 170 Mädchen) und deren Zusammenhänge mit motorischen und kognitiven Leistungen analysiert. Die Händigkeit wurde aufgrund der relativen Geschicklichkeit beider Hände bestimmt. Im Untersuchungszeitraum lässt sich keine Veränderung des Anteils von Rechtshändern (84.8%), Linkshändern (9.8%) und Ambidextern (5.4 %) nachweisen, Jungen sind häufiger linkshändig oder beidhändig als Mädchen. Der Anteil von Linkshändern bei Erstgeborenen, die ein höheres Risiko für Hirnschädigungen aufweisen, ist nicht höher als bei Nachgeborenen. Etwa 16 Prozent der Kinder, vor allem Linkshänder und Ambidexter, aber auch Rechtshänder, wechselten im Untersuchungszeitraum ihre Händigkeit. Linkshändigkeit oder Beidhändigkeit gehen nicht mit verminderten kognitiven oder motorischen Leistungen einher, allerdings erzielten Kinder, die im Untersuchungszeitraum ihre Händigkeit wechselten, schlechtere feinmotorische und kognitive Leistungen als Kinder mit konstanter Händigkeit.

Cultural and environmental influences on footedness: cross-sectional study in urban and semi-urban Malawi

The present study was designed to assess cultural and environmental pressure against left-foot preference in urban and semi-urban Malawi. The findings demonstrated that, when compared to handedness, footedness appeared to be less biased behavioral laterality in culturally restrictive communities. The percentage of responders with negative views on left-foot preference was lower than that on left-hand preference (57% vs. 75%) and a smaller proportion of volunteers suggested that left-footers should be forced to change the foot (63.5% vs. 87.6%). In total, mobilizing and stabilizing tasks scored similar proportions of negative responses. Expectation of inferior performance of the left foot than the right one was the major reason for negative views on left-foot preference. Gender and driving experience had significant but weak effect on the view on left-foot preference. Most of the responders (74%) suggested that left-footers should change the foot in early family environment.

Patterns of handedness and footedness in switched and nonswitched Brazilian left-handers: cultural effects on the development of lateral preferences

In Western societies most left-handers who are pressured to write with the right hand resist the pressure. Searleman and Porac (2001, 2003) studied North American participants and proposed that mixed left-handers, more so than consistent left-handers, would be likely to successfully acquire right-handed writing skills on a long-term basis. In accordance with their two-phenotype hypothesis, the majority of switched left-handers (SLH) in their studies exhibited right-sided asymmetries on other handedness tasks such as throwing, and, in addition, tended to be right-footed. In order to ascertain whether this hypothesis had cross-cultural generality, handedness and footedness data were obtained from 3,716 Brazilian participants. Of the 650 left-handed participants, 62 (9.5%) had successfully switched to right-handed writing. Analyses of preference patterns revealed that the majority of the SLH were left-handed for other tasks, including throwing, and also preferred to kick soccer penalties with their left foot. The results were supportive of a variable rather than a two-phenotype model relating hand preference consistency to successful rightward conversion of the writing hand. The cross-cultural differences found between North American and Brazilian SLH were attributed to divergent socialization training effects and the development of different value orientations in the North versus South American cultural milieu.