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Handedness
Selected AbstractsPrevalence and handedness correlates of traumatic injuries to the permanent incisors in 13,17-year-old adolescents in Erzurum, TurkeyDENTAL TRAUMATOLOGY, Issue 5 2003Varol Canakci Abstract ,,,The objectives of the present study were to explore the relationship between dental trauma and handedness, and to assess the prevalence of traumatic injuries to the permanent incisors of 13,17-year-old patients, seeking treatment for various dental conditions in Erzurum, Turkey. A questionnaire focusing on handedness was administered to these patients. Handedness was assessed by the Edinburgh Handedness Inventory (Oldfield, 1971). Hand preference was divided into two classes for convenience in data analysis: (i) right-handers (GSc from 80 to 100); and (ii) left-handers (GSc from ,80 to ,100). This study included the 13,17-year-old group patients who had GSc as described above. Thus, the present study was carried out on 2180 (1252 male and 928 female, with a mean age of 14.9 years) out of 2392 patients. The clinical examinations and radiographic assessments were performed in full-designed dental chairs. Preliminary analysis showed no differences in rates of handedness with respect to sex and age. Overall, 10.4% of the patients were left-handers. A total of 292 (13.4%) of 2180 patients examined had one or more traumatized permanent incisors. The proportion of dental trauma was significantly higher in males than in females, 17.41% in males as compared to 7.97% in females; and ratio of the affected males to females was about 2.18. Sex difference in the prevalence of traumatized permanent incisors was statistically significant (P < 0.001). That is, males had a significantly higher risk of dental trauma than females (P < 0.001; odds ratio: 2.49; 95% confidence interval (CI) 1.88, 3.23). There was a higher level of traumatized permanent incisors among left-handers than among right-handers. 28.3% of left-handers and 11.7% of right-handers had dental trauma. This difference in the prevalence of traumatized permanent incisors for handedness was statistically significant (P < 0.001). Indeed, left-handers had a significantly higher risk on dental trauma than right-handers (P < 0.001; odds ratio: 3.09; 95% CI 2.23, 4.29). The primary causative factor in the occurrence of trauma was the fall (27.7%). Then came violence and fight as the second most frequent cause of trauma (24%), followed by sports injury (18.8%). Trauma resulting from collisions and traffic accidents were accounted as 13.7 and 11.3% of all cases, respectively. The other causes were 4.5%. In conclusion, the present study suggests that left-handed adolescents have more frequent permanent incisor tooth trauma than right-handed adolescents. Left-handedness, therefore, appears to be a risk factor for trauma in 13,17-year-old adolescents. [source] Psychological functioning and health-related quality of life in adulthood after preterm birthDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 8 2007Stuart R Dalziel FRACP PhD The aim of this study was to determine if preterm birth is associated with socioeconomic status (SES), psychological functioning, and health-related quality of life (HRQoL) in adulthood. We used prospective follow-up of 192 adult offspring of mothers who took part in a randomized controlled trial of antenatal betamethasone for the prevention of neonatal respiratory distress syndrome (66 born at term [33 males, 33 females] 126 born preterm [66 males, 60 females]). Cognitive functioning was assessed using the Wechsler Abbreviated Scale of Intelligence. Working memory and attention was assessed using the Benton Visual Retention Test, the Paced Auditory Serial Addition Test, and the Brown Attention Deficit Disorder Scale. Psychiatric morbidity was assessed using the Beck Depression Inventory II, the State-Trait Anxiety Inventory, and the Schizotypy Traits Questionnaire. Handedness was assessed using the Edinburgh Handedness Inventory. HRQoL was assessed using the Short Form-36 Health Survey. Moderately preterm birth (median gestation 34wks, mean birthweight 1946g [SD 463g]) was not related to later marital status, educational attainment, SES, cognitive functioning, working memory, attention, or symptoms of anxiety or schizotypy at 31 years of age. Preterm birth was associated with fewer symptoms of depression and higher levels of satisfaction in three of the eight HRQoL domains measured (bodily pain, general health perception, and social functioning). Adults who were born moderately preterm have SES, psychological functioning, and HRQoL consistent with those who were born at term. This good long-term outcome cannot be extrapolated to those with early childhood disability or very low birthweights. [source] Quantitative and qualitative evaluation of neuromotor behaviour in children with a specific speech and language disorderINFANT AND CHILD DEVELOPMENT, Issue 1 2002Michele Noterdaeme Abstract Several studies have described problems in a wide area of motor functions in language impaired children. The purpose of this study was to identify the nature of the motor deficits in two subgroups of language impaired children. A standard neurological examination was performed on 18 children with an expressive language disorder and 21 children with a receptive language disorder. The motor performance of the language disordered children was compared with the motor performance of 23 normal children. The standard neurological examination allowed for a qualitative and quantitative assessment of five specific neurological subsystems. Handedness was determined for all children. The language impaired children had more motor problems than the control children on most neurological subsystems. There were few statistically significant differences between the two groups of language impaired children. An excess in left-handedness was established in the group of children with a receptive language disorder. There was a co-occurrence of verbal and non-verbal deficits in language impaired children. As these motor problems put an additional burden on the development of language impaired children, they should be diagnosed as early as possible. Copyright © 2002 John Wiley & Sons, Ltd. [source] Knot-Tying Habits, Tier Handedness, and Experience,JOURNAL OF FORENSIC SCIENCES, Issue 5 2010Robert C. Chisnall M.Ed. Abstract:, Previous research concerning tier handedness, experience and the configuration of simple, habitual knots has been scant and conflicting. Survey data were collected from 21 disparate groups comprising 562 respondents in total. Regardless of experience, respondents tied both Granny and Reef Knots. Dextral tying was dominated by S knots. Left-handers tied Z knots more frequently than right-handers. However, the frequency of S and Z knots relative to tier hand dominance, which is not binary, occurred on a continuum. Averaging all survey tasks, more than 70% of knots tied by dextrals were S, whereas only 56% of those tied by sinistrals were S. These percentages varied somewhat according to specific tying tasks and the number of working ends. Furthermore, tiers' shoelace and parcel knots were not always identical, and a ranked pattern in parcel and shoelace knots was revealed. The examination of habitual knots could benefit criminal investigations. [source] Prevalence and handedness correlates of traumatic injuries to the permanent incisors in 13,17-year-old adolescents in Erzurum, TurkeyDENTAL TRAUMATOLOGY, Issue 5 2003Varol Canakci Abstract ,,,The objectives of the present study were to explore the relationship between dental trauma and handedness, and to assess the prevalence of traumatic injuries to the permanent incisors of 13,17-year-old patients, seeking treatment for various dental conditions in Erzurum, Turkey. A questionnaire focusing on handedness was administered to these patients. Handedness was assessed by the Edinburgh Handedness Inventory (Oldfield, 1971). Hand preference was divided into two classes for convenience in data analysis: (i) right-handers (GSc from 80 to 100); and (ii) left-handers (GSc from ,80 to ,100). This study included the 13,17-year-old group patients who had GSc as described above. Thus, the present study was carried out on 2180 (1252 male and 928 female, with a mean age of 14.9 years) out of 2392 patients. The clinical examinations and radiographic assessments were performed in full-designed dental chairs. Preliminary analysis showed no differences in rates of handedness with respect to sex and age. Overall, 10.4% of the patients were left-handers. A total of 292 (13.4%) of 2180 patients examined had one or more traumatized permanent incisors. The proportion of dental trauma was significantly higher in males than in females, 17.41% in males as compared to 7.97% in females; and ratio of the affected males to females was about 2.18. Sex difference in the prevalence of traumatized permanent incisors was statistically significant (P < 0.001). That is, males had a significantly higher risk of dental trauma than females (P < 0.001; odds ratio: 2.49; 95% confidence interval (CI) 1.88, 3.23). There was a higher level of traumatized permanent incisors among left-handers than among right-handers. 28.3% of left-handers and 11.7% of right-handers had dental trauma. This difference in the prevalence of traumatized permanent incisors for handedness was statistically significant (P < 0.001). Indeed, left-handers had a significantly higher risk on dental trauma than right-handers (P < 0.001; odds ratio: 3.09; 95% CI 2.23, 4.29). The primary causative factor in the occurrence of trauma was the fall (27.7%). Then came violence and fight as the second most frequent cause of trauma (24%), followed by sports injury (18.8%). Trauma resulting from collisions and traffic accidents were accounted as 13.7 and 11.3% of all cases, respectively. The other causes were 4.5%. In conclusion, the present study suggests that left-handed adolescents have more frequent permanent incisor tooth trauma than right-handed adolescents. Left-handedness, therefore, appears to be a risk factor for trauma in 13,17-year-old adolescents. [source] Parental and perinatal factors influencing the development of handedness in captive chimpanzeesDEVELOPMENTAL PSYCHOBIOLOGY, Issue 6 2006William D. Hopkins Abstract It has been proposed that human right handedness is determined by genetic factors associated with the emergence of language, whereas non-human primate handedness is determined by random, non-genetic factors. These different mechanisms account for differences in the distribution of handedness between human and non-human primates. Here we report evidence that genetic factors play a role in the determination of handedness in chimpanzees. We further report that differential rearing has no influence on the expression of handedness in related individuals. Contrary to many theories of the origin of handedness, these results indicate that genetic factors have a significant influence on handedness in chimpanzees. © 2006 Wiley Periodicals, Inc. Dev Psychobiol 48: 428,435, 2006. [source] Fetal handedness and head position preference: A developmental studyDEVELOPMENTAL PSYCHOBIOLOGY, Issue 3 2001J.I.P. de Vries Abstract Hand,head contacts were observed by means of serial ultrasound recordings in 10 healthy fetuses from 12 to 38 weeks of gestational age. Contacts were distinguished as being unimanual or bimanual, and if unimanual, whether they were made with the right or left hand. Both types of contact and ones made unimanually with the right or left hand were identified at each age as to whether they were associated with a preferential head position. A strong unimanual bias was evident at each age except for Week 36. At this age, there was a bimanual bias. Unimanual contacts did not develop a lateralized preference, and neither type of contact established a stable relationship with head position. Furthermore, there was no evidence to support the suggestion that hand contact and head position codevelop to form a preferred ipsilateral synergy. Findings are discussed relative to contradictory evidence from other fetal and neonatal studies. © 2001 John Wiley & Sons, Inc. Dev Psychobiol 39: 171,178, 2001 [source] Cognitive subprocesses and schizophrenia.ACTA PSYCHIATRICA SCANDINAVICA, Issue 2001Objective:,The aim of the study is to demonstrate that deficits of information processing in schizophrenic patients can be isolated with reaction-time (RT) decomposition paradigms. Method:,Three types of visually presented tasks were applied: simple, disjunctive and choice RT-tasks. RT were split into movement latency and time necessary to execute movements. Comparisons of three samples of schizophrenic patients (295.3) with individually matched (age, sex, education and handedness) healthy controls are presented: Sample 1: 10 drug-naive first-onset patients, Sample 2: 10 neuroleptically treated first-onset patients, Sample 3: 10 neuroleptically treated chronically ill patients. Results:,Findings indicate that schizophrenia affects primarily subprocesses in which percepts are translated into appropriate actions (response-selection). Neuroleptic treatment improves processing at this stage but is accompanied by slowing of movement execution. Conclusion:,Response-selection is selectively impaired in first-onset patients. This disturbance, which might be specific for schizophrenia, can be regarded as indication of a disconnection between frontal and posterior areas. [source] fMRI Lateralization of Expressive Language in Children with Cerebral LesionsEPILEPSIA, Issue 6 2006Dianne P. Anderson Summary:,Purpose: Lateralization of language function is crucial to the planning of surgery in children with frontal or temporal lobe lesions. We examined the utility of functional magnetic resonance imaging (fMRI) as a determinant of lateralization of expressive language in children with cerebral lesions. Methods: fMRI language lateralization was attempted in 35 children (29 with epilepsy) aged 8,18 years with frontal or temporal lobe lesions (28 left hemisphere, five right hemisphere, two bilateral). Axial and coronal fMRI scans through the frontal and temporal lobes were acquired at 1.5 Tesla by using a block-design, covert word-generation paradigm. Activation maps were lateralized by blinded visual inspection and quantitative asymmetry indices (hemispheric and inferior frontal regions of interest, at p < 0.001 uncorrected and p < 0.05 Bonferroni corrected). Results: Thirty children showed significant activation in the inferior frontal gyrus. Lateralization by visual inspection was left in 21, right in six, and bilateral in three, and concordant with hemispheric and inferior frontal quantitative lateralization in 93% of cases. Developmental tumors and dysplasias involving the inferior left frontal lobe had activation overlying or abutting the lesion in five of six cases. fMRI language lateralization was corroborated in six children by frontal cortex stimulation or intracarotid amytal testing and indirectly supported by aphasiology in a further six cases. In two children, fMRI language lateralization was bilateral, and corroborative methods of language lateralization were left. Neither lesion lateralization, patient handedness, nor developmental versus acquired nature of the lesion was associated with language lateralization. Involvement of the left inferior or middle frontal gyri increased the likelihood of atypical language lateralization. Conclusions: fMRI lateralizes language in children with cerebral lesions, although caution is needed in interpretation of individual results. [source] Impaired Motor Function in Patients with Psychogenic PseudoseizuresEPILEPSIA, Issue 12 2001Dalma Kalogjera Sackellares Summary: ,Purpose: To evaluate motor speed and grip strength in patients with well-documented psychogenic pseudoseizures. Methods: We analyzed manual motor speed and grip strength in a group of 40 patients with confirmed psychogenic pseudoseizures (without evidence of concomitant epilepsy) and a group of 40 normal controls matched for handedness and gender, and of comparable age. The two groups were compared with respect to manual motor performance with the dominant hand, nondominant hand, and asymmetry between the dominant and nondominant hands. For the patient sample, we reviewed the neurologic history. Results: Patients with pseudoseizures performed more poorly than controls with both dominant and nondominant hands. In addition, pseudoseizure patients failed to demonstrate the dominant-hand advantage observed in the normal control subjects on both tasks. The patient group had a high incidence of head trauma and other antecedent neurologic risk factors, and the proportion of left-handers was 3 times higher than expected. Conclusions: Bilaterally reduced motor speed and grip strength, reduced intermanual performance asymmetry, the high percentage of left-handers, and historical evidence of antecedent insults to the brain indicate that frontal lobe impairment may be common in patients with psychogenic pseudoseizures. [source] VIQ-PIQ Discrepancies in Partial Epilepsy: On the Relation to Lat- eralities of Focal MRI Lesions, P3 Peaks, and Focal Spikes.EPILEPSIA, Issue 2000Osamu Kanazawa Purpose: A number of previous ncurophysiological studies have indicated that the glutamatergic system is important in the induction of epileptiform activity and the dcvelopment of epileptogenesis. Clutamate transport is the primary mechanism of inactivation of syiiaptically released glutamate. GLAST is classified BS an astrocytic transporter and occurs in high concentrations in the ccrebcllum. The pathophysiologic rolc of GLAST in epilepsy is not known in detail. To investigate the role of thc astroglial glutamatc transporter GLAST in epileptogenesis, we compared amygdalu-kindling and pentylenctetrazolc (PTZ) induced seizures in GLAST-deficient mice (GLAST(-/-)) wild-type mice (GLAST(+/+)), and maternal C57Black6/J mice (C57). Purpose: Subtest IQ such as verbal IQ (VIQ) and performance IQ (PIQ) in WAIS or WISC are thought to represent neuropsychological functions of the left and right hemispheres, respectively. The P300 (P3) event-related potential reflects cognitive processes. We do not ye1 know the brain site of P3 origin or how epileptogenic foci (EF) influ- ence P3 potentials. To examine neuropsychological influence by partial epilepsy (PE), we studied VIQ-PIQ discrepancies in PE in relation to lateralities of focal MRI lesions, P3 peaks, and EF. Methods: Thirteen patients showed VIQ-PIQ discrepancies significant at the p7lt;O.O5 level, represented by a>l2-point spread for the WAIS in adults, and a 15-point spread in the WISC in children. We evoked P3 potentials in the individuals with discrepant IQ differences by asking them to keep a mental count of rare tones, including introduction of oddbail tones. EEGs were recorded by the international 10,20 system and P3 peaks were shown in a topographical view by offline analysis. Patients were divided into normal and abnormal groups according to MRI findings, and were examined for the laterali- ties of the dominant side in subtest IQ (conventionally, we regarded higher VIQ as left hemisphere dominant and higher PIQ as right hemisphere dominant), P3 peaks, and EF. We did not correlate results with lert or right handedness. Results: Five patients (38.5%) were in the normal group and 8 patients (61.5%) were in the abnormal group. Concordance of the lateralities in P3 peaks and dominant side in subtest IQ was shown in 1 patient (20%) in the normal group and 5 patients (62.5%) in the abnormal group. In the normal group, all patients showed contralateral P3 peak shift to EF, and all except I patient showed contralateral P3 peak shift to the dominant side in subtest IQ. The other 3 patients in the abnormal group showed unilateral focal cortical dysplasias (FCD), ipsilateral P3 shift, and contralateral dominant side in subtest IQ to the focal MRI lesions. Conclusion: In our partial epilepsy series with VIQ-PIQ discrepancies, concordance of the lateralities in P3 peaks and dominant side in subtest IQ was shown in < half of the patients. Epileptogenic foci seem to have 3 different grades of influence on P3 peak shift and dominant side in subtest IQ according to the severities of accompanying focal MRI lesions: 1. Without MRI lesions, EF can make P3 peak shift contralaterally, but the dominant side in the subtest IQ shift ipsilaterally; 2. With less severe focal MRI lesions such as hippocampal atrophy etc., EF can make not only P3 peaks but also the dominant side in the subtest IQ shift contralaterally; 3. With severe focal MRI lesions such as FCD, EF can make the dominant side in the subtest IQ shift contralaterally, but the P3 peak may shift ipsilaterally. Epileptogenic foci without MRI lesions seem to control ipsilateral P3 potentials. MRI lesions render a hemisphere unlikely to become dominant, but epileptogenic foci can coexist with apparently normal neuropsychological function. [source] Lateralization of hand skill in bipolar affective disorderGENES, BRAIN AND BEHAVIOR, Issue 8 2007J. Savitz Diverse strands of evidence suggest that schizophrenia is associated with an excess of left and mixed handedness, reflecting anomalous cerebral lateralization. Genetic studies have indicated a degree of overlap between bipolar disorder (BPD) and schizophrenia. Nevertheless, pattern of handedness and degree of lateralization have not been explicitly tested in BPD. We measured handedness, footedness and relative manual dexterity in a sample of 47 families comprising BPD probands and their bipolar-spectrum and unaffected relatives (N = 240). The BPD I sample (N = 55) was significantly more lateralized on handedness, footedness and relative manual dexterity than their unaffected relatives (N = 66). They were also more lateralized than their relatives with other psychiatric diagnoses. No evidence of excess mixed handedness or footedness was observed in the BPD I sample. We raise the possibility that schizophrenia and BPD I differ in that disproportionate left-hemisphere dominance in BPD I is associated with right-hemisphere dysfunction leading to deficits in emotional regulation. Given our results, we hypothesized that degree of lateralization may be a phenotypic marker or endophenotype for BPD I. We therefore conducted a family-based genetic association analysis with this quantitative trait. Relative hand skill was significantly associated with a functional variant in the catechol- O -methyltransferase gene. We speculate that this polymorphism may influence brain lateralization. [source] Formation of Chiral Mesopores in Conducting Polymers by Chiral-Lipid-Ribbon Templating and "Seeding" Route,ADVANCED FUNCTIONAL MATERIALS, Issue 18 2008Chaxing Fan Abstract Conducting polymer nanofibers with controllable chiral mesopores in the size, the shape, and handedness have been synthesized by chiral lipid ribbon templating and "seeding" route. Chiral mesoporous conducting poly(pyrrole) (CMPP) synthesized with very small amount of chiral amphiphilic molecules (usually,<,3%) has helically twisted channels with well-defined controllable pore size of 5,20,nm in central axis of the twisted fibers. The structure and chirality of helical mesopores have been characterized by high-resolution transmission electron microscope (HRTEM), scanning electron microscope (SEM) and electron tomography. The average pore diameters of chiral mesopores were approximately estimated from the N2 adsorption,desorption data and calculated by the conversion calculation from helical ribbons to a rectangular straight tape. The pore size of CMPP has been controlled by choosing different alkyl chain lengths of chiral lipid molecules or precisely adjusting the H2O/EtOH volume ratio. [source] Greater leftward lateralization of the inferior frontal gyrus in second language learners with higher syntactic abilitiesHUMAN BRAIN MAPPING, Issue 11 2009Arihito Nauchi Abstract There is a great individual variability for acquiring syntactic knowledge in a second language (L2). Little is, however, known if there is any anatomical basis in the brain for individual differences in syntactic acquisition. Here we examined brain structures in 95 nonnative speakers of English, including 78 high-school students and 17 adult international students. We found a significant correlation between the performance of a syntactic task and leftward lateralization of a single region in the triangular part (F3t) of the inferior frontal gyrus, which has been proposed as the grammar center. Moreover, this correlation was independent of the performance of a spelling task, age, gender, and handedness. This striking result suggests that the neural basis for syntactic abilities in L2 is independent of that for lexical knowledge in L2, further indicating that the individual differences in syntactic acquisition are related to the lateralization of the grammar center. Hum Brain Mapp, 2009. © 2009 Wiley-Liss, Inc. [source] The mirror-neuron system and handedness: A "right" world?HUMAN BRAIN MAPPING, Issue 11 2008Maria A. Rocca Abstract To assess the relationship between the mirror-neuron system (MNS), an observation-execution matching system, and handedness, we acquired functional magnetic resonance imaging from 11 right-handed (RH) and eight left-handed (LH) subjects to identify regions involved in processing action (execution and observation) of the right and left upper limbs. During the execution tasks, LH subjects had a more bilateral pattern of activation than RH. An interaction between handedness and hand observed during the observation conditions was detected in several areas of the MNS and the motor system. The within- and between-groups analyses confirmed different lateralizations of the MNS and motor system activations in RH and LH subjects during the observation tasks of the dominant and nondominant limbs. The comparison of the execution vs. observation task demonstrated that during the execution task with their dominant limbs, RH subjects activated areas of the motor system in the left hemisphere, whereas LH subjects also activated areas of the MNS. During the execution task with the nondominant limbs, both groups activated regions of the MNS and motor system. Albeit this study is based on a small sample, the patterns of MNS activations observed in RH and LH subjects support the theory that suggests that this system is involved in brain functions lateralization. In LH people, this system might contribute to their adaptation to a world essentially built for right-handers through a mechanism of mirroring and imitation. Hum Brain Mapp, 2008. © 2007 Wiley-Liss, Inc. [source] fMRI study of language lateralization in children and adultsHUMAN BRAIN MAPPING, Issue 3 2006Jerzy P. Szaflarski Abstract Language lateralization in the brain is dependent on family history of handedness, personal handedness, pathology, and other factors. The influence of age on language lateralization is not completely understood. Increasing left lateralization of language with age has been observed in children, while the reverse has been noted in healthy young adults. It is not known whether the trend of decreasing language lateralization with age continues in the late decades of life and at what age the inflection in language lateralization trend as a function of age occurs. In this study, we examined the effect of age on language lateralization in 170 healthy right-handed children and adults ages 5,67 using functional MRI (fMRI) and a verb generation task. Our findings indicate that language lateralization to the dominant hemisphere increases between the ages 5 and 20 years, plateaus between 20 and 25 years, and slowly decreases between 25 and 70 years. Hum Brain Mapp, 2005. © 2005 Wiley-Liss, Inc. [source] Coronary heart disease is associated with regional grey matter volume loss: implications for cognitive function and behaviourINTERNAL MEDICINE JOURNAL, Issue 7 2008O. P. Almeida Abstract Coronary heart disease (CHD) has been associated with impaired cognition, but the mechanisms underlying these changes remain unclear. We designed this study to determine whether adults with CHD show regional brain losses of grey matter volume relative to controls. We used statistical parametric mapping (SPM5) to determine regional changes in grey matter volume of T1 -weighted magnetic resonance images of 11 adults with prior history of myocardial infarction relative to seven healthy controls. All analyses were adjusted for total grey and white matter volume, age, sex and handedness. CHD participants showed a loss of grey matter volume in the left medial frontal lobe (including the cingulate), precentral and postcentral cortex, right temporal lobe and left middle temporal gyrus, and left precuneus and posterior cingulate. CHD is associated with loss of grey matter in various brain regions, including some that play a significant role in cognitive function and behaviour. The underlying causes of these regional brain changes remain to be determined. [source] A neuropsychological dimension for anchoring effectsJOURNAL OF BEHAVIORAL DECISION MAKING, Issue 5 2005John D. Jasper Abstract Previous research has shown that strength of handedness predicts differences in sensory illusions, Stroop interference, episodic memory, and beliefs about body image and the origin of species. Recent evidence also suggests handedness differences in the susceptibility to information framing and persuasion. The present paper extends this line of work to decision anchoring effects. In Experiment 1, 131 introductory psychology students responded to 12 real-world knowledge questions after being given random, uninformative high or low anchors. Results indicated that "strong-handers" showed larger anchoring effects than "mixed-handers." In Experiment 2, 89 introductory psychology students responded to 6 real-world knowledge questions in a modified, two-step anchoring task in which participants were given a credible source for the anchored information and asked to give pre- and post-anchor estimates. In contrast to Experiment 1, results revealed that mixed- and strong-handers were affected similarly by anchoring. In Experiment 3, 158 students were asked to estimate the answer to one of two versions of 8! (8,×,7,×,6,×,5,×,4,×,3,×,2,×,1 or 1,×,2,×,3,×,4,×,5,×,6,×,7,×,8),a multiplication problem in which the high and low anchors are inherently informative. Here, mixed-handers showed larger anchoring effects than strong-handers. A theory centered around the notion of hemispheric specialization and the communication between the two halves of the brain as well as arguments about the informativeness of anchors, metacognition, and recent theorizing in the anchoring literature are used to account for these data. Copyright © 2005 John Wiley & Sons, Ltd. [source] Spontaneous segregation on a hybrid chiral surfaceJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 10 2008Szabelski Abstract Segregation of enantiomers in two-dimensional adsorbed layers is a process that is usually controlled by anisotropic directional interactions between adsorbed molecules. In this contribution, we propose a simple theoretical model in which the chiral segregation occurs even though the lateral interactions are neglected. In particular, we consider a solid surface composed of two domains with different patterns of active sites being mirror images of each other. The domains of opposite handedness represent crystal facets of a composite chiral material which are adjoined to form a heterochiral adsorbing surface. To explore equilibrium properties of the system, we use Canonical Ensemble Monte Carlo method for a square lattice. The influence of factors such as energetic properties of the surface and density of the adsorbed layer on the extent of separation is examined. The obtained results indicate that effective two-dimensional separation on the hybrid chiral surface assumed in our model can be achieved only at sufficiently low adsorbate densities. The results also suggest that the segregation on the hybrid surface would be a promising method of enantiodiscrimination for those chiral molecules which do not exhibit strong lateral interactions. © 2008 Wiley Periodicals, Inc. J Comput Chem 2008 [source] Knot-Tying Habits, Tier Handedness, and Experience,JOURNAL OF FORENSIC SCIENCES, Issue 5 2010Robert C. Chisnall M.Ed. Abstract:, Previous research concerning tier handedness, experience and the configuration of simple, habitual knots has been scant and conflicting. Survey data were collected from 21 disparate groups comprising 562 respondents in total. Regardless of experience, respondents tied both Granny and Reef Knots. Dextral tying was dominated by S knots. Left-handers tied Z knots more frequently than right-handers. However, the frequency of S and Z knots relative to tier hand dominance, which is not binary, occurred on a continuum. Averaging all survey tasks, more than 70% of knots tied by dextrals were S, whereas only 56% of those tied by sinistrals were S. These percentages varied somewhat according to specific tying tasks and the number of working ends. Furthermore, tiers' shoelace and parcel knots were not always identical, and a ranked pattern in parcel and shoelace knots was revealed. The examination of habitual knots could benefit criminal investigations. [source] An Evaluation of Determination of Handedness Using Standard Osteological Measurements,JOURNAL OF FORENSIC SCIENCES, Issue 4 2008Marie Elaine Danforth Ph.D. Abstract:, Numerous studies have assessed side dominance assuming arm bones on the side of handedness will be larger, but concerns over sample size or replicability of measurements usually emerged. Attempting to improve upon these limitations, this investigation analyzes patterns of side difference for standard length and transverse dimensions of the scapula, clavicle, humerus, ulna, and radius for 137 individuals of known handedness. The results showed that with few exceptions, the right side of the skeleton was consistently larger in most individuals regardless of side dominance. Combinations of other measurements previously suggested to be indicative of handedness as well as the use of discriminant analysis also failed to provide reliable estimators. These findings are likely related to the fact that activities of modern individuals are generally not sufficiently unilateral in their stresses to cause asymmetrical development in the arm bones. Therefore, it is recommended that other means be developed to assess side dominance. [source] Cerebral dominance and schizophrenia-spectrum disorders in adults with intellectual disabilityJOURNAL OF INTELLECTUAL DISABILITY RESEARCH, Issue 6 2000D. Rowe Abstract Studies of the general population without intellectual disability have suggested an association between atypical handedness and schizophrenia-spectrum disorders (SSDs). Mixed handedness is taken as an index of diminished cerebral dominance or laterality. The present study addressed the question of whether such findings extend to the neurodevelopmentally ,at risk' population of adults with intellectual disability and SSDs compared with appropriate controls. Fourteen patients with a dual diagnosis of intellectual disability and SSD were compared with 14 controls with intellectual disability alone. Assessments of self-reported hand preference and relative hand skill were completed. Self-report of hand preference revealed highly significantly greater mixed-handedness in the SSD group. Furthermore, relative hand skill performance was significantly diminished for the dominant hand. The discrepancy between dominant and non-dominant hand functioning was lower in the SSD group and this association was highly significant. The results of the present study support the usefulness of such detailed laterality assessment in this population. Mixed laterality, over and above that of the population with general intellectual disability and developmental disorder, was associated with SSD. These results are consistent with the neurodevelopmental hypothesis of schizophrenia and its cognitive neuropsychiatric/neuropsychological sequelae. [source] Chewing side preference as a type of hemispheric lateralityJOURNAL OF ORAL REHABILITATION, Issue 5 2004J. Nissan summary, Chewing side preference is a factor that could effect prosthodontic treatment. The purpose of this study was to determine whether chewing side was another type of hemispheric lateralization comparable with footedness, handedness, eyedness and earedness. Chewing side preference was tested in 189 subjects of whom 84 were partially edentulous, 98 had a full compliment of dental units (81 included implant-supported restoration restoring the missing teeth and 17 with fully intact dentitions), and seven were fully edentulous, restored with complete dentures. Laterality tests were carried out for the first cycle of mastication, handedness, footedness, earedness and eyedness and patient questionnaire. Most patients preferred chewing on the right side (78,3%) and were right sided. Chewing side preference correlated with other tested hemispherical lateralities. Missing teeth, occlusion type, lateral guidance, gender, implant-supported restorations and complete dentures do not affect the side preference for chewing. This presents a strong argument that chewing side preference is centrally controlled and provides food for thought regarding its significance in prosthodontics. [source] Mechanisms of Postural Control in Alcoholic Men and Women: Biomechanical Analysis of Musculoskeletal Coordination During Quiet StandingALCOHOLISM, Issue 3 2010Edith V. Sullivan Background:, Excessive sway during quiet standing is a common sequela of chronic alcoholism even with prolonged sobriety. Whether alcoholic men and women who have remained abstinent from alcohol for weeks to months differ from each other in the degree of residual postural instability and biomechanical control mechanisms has not been directly tested. Method:, We used a force platform to characterize center-of-pressure biomechanical features of postural sway, with and without stabilizing conditions from touch, vision, and stance, in 34 alcoholic men, 15 alcoholic women, 22 control men, and 29 control women. Groups were matched in age (49.4 years), general intelligence, socioeconomic status, and handedness. Each alcoholic group was sober for an average of 75 days. Results:, Analysis of postural sway when using all 3 stabilizing conditions versus none revealed diagnosis and sex differences in ability to balance. Alcoholics had significantly longer sway paths, especially in the anterior,posterior direction, than controls when maintaining erect posture without balance aids. With stabilizing conditions the sway paths of all groups shortened significantly, especially those of alcoholic men, who demonstrated a 3.1-fold improvement in sway path difference between the easiest and most challenging conditions; the remaining 3 groups, each showed a ,2.4-fold improvement. Application of a mechanical model to partition sway paths into open-loop and closed-loop postural control systems revealed that the sway paths of the alcoholic men but not alcoholic women were characterized by greater short-term (open-loop) diffusion coefficients without aids, often associated with muscle stiffening response. With stabilizing factors, all 4 groups showed similar long-term (closed loop) postural control. Correlations between cognitive abilities and closed-loop sway indices were more robust in alcoholic men than alcoholic women. Conclusions:, Reduction in sway and closed-loop activity during quiet standing with stabilizing factors shows some differential expression in men and women with histories of alcohol dependence. Nonetheless, enduring deficits in postural instability of both alcoholic men and alcoholic women suggest persisting liability for falling. [source] Side-chain supramolecular polymers with induced supramolecular chirality through H-bonding interactionsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 16 2008Francisco Vera Abstract Side-chain supramolecular polymers that show columnar mesomorphism have been prepared through H-bonding interactions between a polyvinylpyridine polymer as H-acceptor and different H-donors derived from benzoic acid. These compounds have been designed according to a promesogenic structure, that is, either disk-like or banana-like, to promote stacking and therefore the formation of columnar arrangements. IR studies confirmed the formation of H-bonds and demonstrated that the H-bond intensity decreases upon increasing temperature. The mesophase organizations were studied by polarized optical microscopy, differential scanning calorimetry, and X-ray diffraction. Associations containing poly-3-methyl-4-vinylpyridine showed supramolecular optical activity, as evidenced by circular dichroism studies on thin films. It is proposed that these supramolecular polymers adopt a helical structure that can be biased toward a given handedness by virtue of the configuration of the stereogenic centers in the peripheral tails of the acids. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5528,5541, 2008 [source] fMRI BOLD Response to the Eyes Task in Offspring From Multiplex Alcohol Dependence FamiliesALCOHOLISM, Issue 12 2007Shirley Y. Hill Background:, Increased susceptibility for developing alcohol dependence (AD) may be related to structural and functional differences in brain circuits that influence social cognition and more specifically, theory of mind (ToM). Alcohol dependent individuals have a greater likelihood of having deficits in social skills and greater social alienation. These characteristics may be related to inherited differences in the neuroanatomical network that comprises the social brain. Methods:, Adolescent/young adult participants from multiplex AD families and controls (n = 16) were matched for gender, age, IQ, education, and handedness and administered the Eyes Task of Baron-Cohen during functional magnetic resonance imaging (fMRI). Results:, High-risk (HR) subjects showed significantly diminished blood oxygen level dependent (BOLD) response in comparison with low-risk control young adults in the right middle temporal gyrus (RMTG) and the left inferior frontal gyrus (LIFG), areas that have previously been implicated in ToM tasks. Conclusions:, Offspring from multiplex families for AD may manifest one aspect of their genetic susceptibility by having a diminished BOLD response in brain regions associated with performance of ToM tasks. These results suggest that those at risk for developing AD may have reduced ability to empathize with others' state of mind, possibly resulting in diminished social skill. [source] A new approach to measuring high-resolution magnetic Compton profilesJOURNAL OF SYNCHROTRON RADIATION, Issue 2 2006H. Kawata It is demonstrated that long-term stability in the polarization of incident photons delivered from an insertion device makes it possible to measure magnetic Compton profiles with a momentum resolution of 0.15 atomic units or better, without employing a solid-state detector and the traditional method of reversing the external magnetic field or the handedness of the polarization of incident photons in an asynchronous cycle with a short period of tens to hundreds of seconds. [source] Three Conundrums of Language LateralizationLINGUISTICS & LANGUAGE COMPASS (ELECTRONIC), Issue 1-2 2007Kathleen Baynes The lateralization of language to the left hemisphere of the brain in most right-handed individuals is well established; however, this arrangement has no widely accepted theoretical explanation. The distribution of language across the cerebral hemispheres raises issues and contradictions that are difficult for any theory to accommodate. In this article, we review three puzzles about the lateralization of language: (1) the clinical literature reveals profound deficits in language only after left-hemisphere damage, but the brain imaging literature shows bilateral activation in most language tasks; (2) language is left-hemisphere dominant in most individuals yet deviation from this pattern does not result in language dysfunction; and (3) lateralization and handedness are related, but the factors that underlie this relation are unknown. We also briefly discuss evolutionary and genetic theories that have been advanced to explain lateralization. [source] Control of Induced Chirality in Optically Active Poly(N-propargylcarbamate) Films by Solvent VaporMACROMOLECULAR RAPID COMMUNICATIONS, Issue 15 2009Toshiyuki Fukushima Abstract Chiral polyethyne derivatives with lyotropic liquid-crystalline properties are found to be able to self-assemble, forming two chiral organizations with opposite handedness in solid thin films by selection of the casting solvent and its concentration. After the film preparation, chiral organization could also be induced by simple exposure to an appropriate organic solvent's vapor for several minutes without thermal treatment. Furthermore, irreversible inversion of the handedness of the chiral organization in the film could be achieved by exposure to solvent vapor. [source] Ventricular cerebrospinal fluid lactate is increased in chronic fatigue syndrome compared with generalized anxiety disorder: an in vivo 3.0 T 1H MRS imaging study,NMR IN BIOMEDICINE, Issue 3 2009Sanjay J. Mathew Abstract Chronic fatigue syndrome (CFS) is a controversial diagnosis because of the lack of biomarkers for the illness and its symptom overlap with neuropsychiatric, infectious, and rheumatological disorders. We compared lateral ventricular volumes derived from tissue-segmented T1 -weighted volumetric MRI data and cerebrospinal fluid (CSF) lactate concentrations measured by proton MRS imaging (1H MRSI) in 16 subjects with CFS (modified US Centers for Disease Control and Prevention criteria) with those in 14 patients with generalized anxiety disorder (GAD) and in 15 healthy volunteers, matched group-wise for age, sex, body mass index, handedness, and IQ. Mean lateral ventricular lactate concentrations measured by 1H MRSI in CFS were increased by 297% compared with those in GAD (P,<,0.001) and by 348% compared with those in healthy volunteers (P,<,0.001), even after controlling for ventricular volume, which did not differ significantly between the groups. Regression analysis revealed that diagnosis accounted for 43% of the variance in ventricular lactate. CFS is associated with significantly raised concentrations of ventricular lactate, potentially consistent with recent evidence of decreased cortical blood flow, secondary mitochondrial dysfunction, and/or oxidative stress abnormalities in the disorder. Copyright © 2008 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||