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M B Bulman-Fleming

Publications and source records attributed to M B Bulman-Fleming.

15 recordsLinked to original sources
PubMed2001

Concurrent verbal and emotion laterality effects exhibited by normally achieving and learning disabled children.

This study assessed both left- and right-hemisphere functions simultaneously when two-syllable words differing only in the initial stop consonant and spoken in different emotional tones were paired dichotically. Seventy-two right-handed normally achieving children, 12 boys and 12 girls at each of grades 1, 3, and 5, were instructed to detect either the presence of a specific word or of a specific emotion. In addition, 30 right-handed learning disabled (LD) children (age-matched to the normal controls) were assessed to determine whether LD children distribute verbal and nonverbal functions to different hemispheres. Results indicated that although both control and LD children demonstrated an overall REA for word stimuli and an LEA for emotional stimuli, and that emotional stimuli were easier to process than word stimuli, LD children were less accurate in processing both types of stimuli than their control counterparts. 'Complementary specialization,' as assessed through distribution of laterality effects, was found to be greater for control children than for LD children. However, the lack of consistency in complementary specialization found among the three developmental grade levels may be indicative that independent brain mechanisms underlying verbal and emotional processing have yet to be fully established in children. Further, in contrast to adult findings, a larger LEA was obtained for the emotion 'happy' than for the emotion 'sad.' It was concluded that whereas independent hemisphere processing for words and emotions is somewhat prevalent for control children, LD children might not be as strongly lateralized for opposite hemisphere processing of these functions.

Analysis of Variance↗
PubMed1999

Visual temporal asymmetries are related to asymmetries in linguistic perception.

There are numerous recent reports of low-level temporal asymmetries favouring the left hemisphere, and increasing speculation that the left hemisphere's relative superiority at linguistic processing may be related to these asymmetries. The present study sought to test this claim by assessing linguistic lateralization with the Fused Dichotic Words Test and visual temporal asymmetries with a lateralized version of an inspection-time test in a sample of 40 participants balanced for sex and handedness. We found evidence for a significant right-visual-field (left-hemisphere) advantage for accuracy on the inspection-time task, F(1,36)=4.38, P = 0.043, and this asymmetry was significantly correlated with laterality scores on the linguistic dichotic-listening task, r = 0.306, P < 0.028 before disattenuation, and r = 0.486 after disattenuation. This result supports the position that low-level temporal asymmetries are related to asymmetries in linguistic processing.

Adult↗
PubMed1998

Footedness is a better predictor than is handedness of emotional lateralization.

A tremendous amount of experimental work has attempted to identify reliable behavioural predictors of cerebral lateralization. Preferred handedness has been the most popular predictor, but some recent reports suggest that preferred footedness may serve as a more accurate predictor of functional laterality, especially in the left-handed population. The present study sought to test this claim by selectively recruiting individuals with either 'crossed' lateral preferences (right-handed and left-footed or left-handed and right-footed) or 'uncrossed' lateral preferences (right-handed and right-footed or left-handed and left-footed). Lateralization of emotional perception was assessed with two blocks of the dichotic Emotional Words Test (EWT), and lateral preference for both handedness and footedness was assessed using self-report questionnaires. Ear advantage on the dichotic task varied significantly with preferred foot (P=0.003), but not with preferred hand. Cerebral lateralization may be more related to footedness than to other lateral preferences.

Adult↗
PubMed1998

Arousal mediates relations among medial paw preference, lateral paw preference, and spatial preference in the mouse.

Rodents exhibit two well-documented behavioural lateralities: spatial preference and paw preference. Waters and Denenberg [36] have identified two seemingly independent factors of paw preference: medial and lateral paw preference. In the present work, the relations among spatial preference (SP), medial paw preference (MPP), and lateral paw preference (LPP) during states of high and low arousal were examined. These preferences were measured in terms of direction, which describes the side of the preference regardless of strength, and degree, which describes the strength of the preference regardless of direction. A strong positive correlation between LPP and SP was found during periods of high, but not low, arousal. A negative correlation between the degree components of LPP and MPP was found during the low, but not high, arousal periods.

Animals↗
PubMed1997

Mouse paw preference: effects of variations in testing protocol.

Two experiments using two inbred strains of mice were conducted to study mouse paw preference. In the first study, 250 (50 x 5) paw reaches from each of 12 male and 12 female C57BL/6J mice were observed over an 8-week period using the Collins paw preference apparatus to investigate questions relating to the independence of reaches, the size of the tube into which the animals reach for flakes of food, and practise effects. Animals appeared to be much more highly lateralized when two independent reaches per day for 25 days (I protocol) were observed than when 50 reaches were observed in a single session (S protocol). Paradoxically, however, we found no evidence for the lack of independence of reaches when we examined the sequences of reaches performed by animals under the S protocol conditions. With practise, animals became slightly more lateralized, but there were no effects of sex, and approximately equal numbers of mice were left-pawed as were right-pawed. The size of the tube had no effect. The second study used 30 BALB mice, each of which was tested with both the I and S protocols, with order of testing counterbalanced. There was a significant protocol x order interaction such that those doing S first were more highly lateralized on the I task, but those doing I first were highly lateralized on both tasks.

Animals↗
PubMed1996

Associations among familial sinistrality, allergies, and developmental language disorders.

Here we report the results of a study that tested what has become known as the Geschwind hypothesis (Geschwind & Galaburda, 1987). This study involved 526 people who were tested by an allergist for IgE-mediated allergies and who filled out a 12-item handedness questionnaire that also included questions about eyedness, prevalence of left-handedness in the immediate family, and familial developmental language problems. A series of log-linear analyses revealed that if the definition of "anomalous" included left-handedness and having a first-order left-handed relative, one was indeed more likely to be allergic than were those not so classified. When the definition of anomalous simply included those classified as left-handed, the results were not significant. Parallel findings resulted when the criterion variable was the presence of developmental language disorders. No evidence was found for relations between allergies and developmental language problems.

Adolescent↗
PubMed1994

Laterality effects in normal subjects: evidence for interhemispheric interactions.

In this review we describe three methods of research that have been used to study relationships between the cerebral hemispheres in normal human subjects. We briefly mention reaction-time studies, which have been used to measure interhemispheric transmission time; more pertinent to laterality effects, however, are lateralized visual field studies, in which stimuli can be presented either unilaterally or to both visual fields simultaneously, and dichotic listening studies, wherein different stimuli are presented to the two ears simultaneously. Recent examples from the literature of experiments employing these techniques are discussed as they pertain to an understanding of interhemispheric interaction. Some suggestions are offered concerning appropriate procedures for studying interhemispheric interactions in normal human subjects.

Attention↗
PubMed1994

Evaluating the empirical support for the Geschwind-Behan-Galaburda model of cerebral lateralization.

The Geschwind-Behan-Galaburda (GBG) model of cerebral lateralization provides a complex but testable theory of the origins and associates of cerebral lateralization. An overall evaluation of the model suggest that it is not well supported by empirical evidence and that in the case of several key theoretical areas, the evidence that does exist is inconsistent with the theory. In particular: the concept of "anomalous dominance" is shown to be theoretically and methodologically flawed; a meta-analysis of the relationship between handedness and immune disorders finds a marginal overall association, and while three conditions (allergies, asthma, and ulcerative colitis) do show significant associations with left-handedness, two other conditions (myasthenia gravis and arthritis) show significant negative associations with left-handedness. Finally, a review of the origins of the neural crest, and its associations, suggests there is almost no empirical support for the GBG theoretical model in this area.

Autistic Disorder↗
PubMed1994

Simultaneous verbal and affective laterality effects.

By analyzing the error scores of normal participants asked to identify a specific word spoken in a specific tone of voice (for example, the word "tower" spoken in a happy tone of voice), we have been able to demonstrate concurrent verbal and affective cerebral laterality effects in a dichotic listening task. The targets comprised the 16 possible combinations of four two-syllable words spoken in four different tones of voice. There were 128 participants equally divided between left- and right-handers, with equal numbers of each sex within each handedness group. Each participant responded to 144 trials on the dichotic task, and filled in the 32-item Waterloo Handedness Questionnaire. Analysis of false positive responses on the dichotic task (responding "yes" when only the verbal or only the affective component of the target was present, or when both components were present but were at opposite ears) indicated that significantly more errors were made when the verbal aspect of the target appeared at the right ear (left hemisphere) and the emotional aspect was at the left ear (right hemisphere) than when the reverse was the case. A single task has generated both effects, so that differences in participants' strategies or the way in which attention is biased cannot account for the results. While the majority of participants showed a right-ear advantage for verbal material and a left-ear advantage for nonverbal material, these two effects were not correlated, suggesting that independent mechanisms probably underly the establishment of verbal and affective processing. We found no significant sex or handedness effects, though left-handers were much more variable than were right-handers. There were no significant correlations between degree of handedness as measured on the handedness questionnaire and extent of lateralization of verbal or affective processing on the dichotic task. We believe that this general technique may be able to provide information as to the nature and extent of interhemispheric integration of information, and is easily adaptable to other modalities, thus holds great promise for future research.

Adult↗
PubMedDate not supplied

Linguistic lateralization and asymmetries in interhemispheric transmission time.

The Interhemispheric Conduction Delay (ICD) theory of cerebral lateralization claims that longer interhemispheric transfer times (IHTT's) should result in greater functional lateralization for time-critical tasks. IHTT was estimated in 40 normal participants using both a visual and an auditory version of the Poffenberger (1912) paradigm. There was a significant response-hand by side-of-presentation interaction, and the length of IHTT for auditory information being transferred from the right to left hemisphere was significantly related to linguistic lateralization as assessed with a dichotic-listening task. These results support the ICD theory of cerebral lateralization.

Brain↗
PubMedDate not supplied

Tactile gap detection and language lateralization.

Recent work suggests that hemispheric language lateralization might be related to the fine-grained temporal discriminations that are required for linguistic processing (Nicholls, 1996). Studies concerning tactile processing have also shown a significant left-hemisphere (L-H) advantage for tactile gap detection (Nicholls & Whelan, 1997). We hypothesized that language and tactile processing are both preferentially processed by the left hemisphere because it is specialized for tasks requiring fine-grained temporal resolution. Thirty-two participants (16 right and 16 left handers) were tested for both linguistic processing (using the Fused Dichotic Words Test (FDWT)) and tactile gap detection. Both right and left handers showed a significant L-H advantage for both language processing and tactile gap detection. The present study supports recent claims that language lateralization is attributable to the left hemisphere's better suitability to process tasks that require fine-grained temporal resolution.

Female↗