scholarly journals Behavioural laterality in foraging bottlenose dolphins ( Tursiops truncatus )

2019 ◽  
Vol 6 (11) ◽  
pp. 190929 ◽  
Author(s):  
J. Daisy Kaplan ◽  
Samantha Y. Goodrich ◽  
Kelly Melillo-Sweeting ◽  
Diana Reiss
Keyword(s):  
Hemispheric Specialization ◽  
Bottlenose Dolphins ◽  
Population Level ◽  
The Bahamas ◽  
Left Turn ◽  
Sharp Turn ◽  
Visuospatial Processing ◽  
The Right ◽  
Production Mechanisms ◽  
Side Bias

Lateralized behaviour is found in humans and a wide variety of other species. At a population level, lateralization of behaviour suggests hemispheric specialization may underlie this behaviour. As in other cetaceans, dolphins exhibit a strong right-side bias in foraging behaviour. Common bottlenose dolphins in The Bahamas use a foraging technique termed ‘crater feeding’, in which they swim slowly along the ocean floor, scanning the substrate using echolocation, and then bury their rostrums into the sand to obtain prey. The bottlenose dolphins off Bimini, The Bahamas, frequently execute a sharp turn before burying their rostrums in the sand. Based on data collected from 2012 to 2018, we report a significant right-side (left turn) bias in these dolphins. Out of 709 turns recorded from at least 27 different individuals, 99.44% ( n = 705) were to the left (right side and right eye down) [ z = 3.275, p = 0.001]. Only one individual turned right (left side and left eye down, 4/4 turns). We hypothesize that this right-side bias may be due in part to the possible laterization of echolocation production mechanisms, the dolphins' use of the right set of phonic lips to produce echolocation clicks, and a right eye (left hemisphere) advantage in visual discrimination and visuospatial processing.

Hemispheric Asymmetry in Categorical Versus Coordinate Visuospatial Processing Revealed by Temporary Cortical Deactivation

2001 ◽  
Vol 13 (8) ◽  
pp. 1088-1096 ◽  
Author(s):  
Scott D. Slotnick ◽  
Lauren R. Moo ◽  
Mark A. Tesoro ◽  
John Hart
Keyword(s):  
Left Hemisphere ◽  
Task Difficulty ◽  
Right Hemisphere ◽  
Hemispheric Specialization ◽  
Cognitive Test ◽  
Hemispheric Processing ◽  
Visuospatial Processing ◽  
Sodium Amobarbital ◽  
The Right ◽  
Better Than

Kosslyn (1987) proposed that the left hemisphere is better than the right hemisphere at categorical visuospatial processing while the right hemisphere is better than the left hemisphere at coordinate visuospatial processing. In 134 patients, one hemisphere (and then usually the other) was temporarily deactivated by intracarotid injection of sodium amobarbital. After a hemisphere was deactivated, a cognitive test battery was conducted, which included categorical and coordinate visuospatial tasks. Using this technique, the processing capabilities of the intact hemisphere could be determined, thus directly testing Kosslyn's hypothesis regarding hemispheric specialization. Specifically, if the left hemisphere does preferentially process categorical visuospatial relationships, then its deactivation should result in more errors during categorical tasks than right hemisphere deactivation and vise versa for the right hemisphere regarding coordinate tasks. The pattern of results obtained in both categorical and coordinate tasks was consistent with Kosslyn's hypothesis when task difficulty was sufficiently high. However, when task difficulty was low, a left hemispheric processing advantage was found for both types of tasks indicating that: (1) the left hemisphere may be better at “easy” tasks regardless of the type of task and (2) the proposed hemispheric processing asymmetry may only become apparent during sufficiently demanding task conditions. These results may explain why some investigators have failed to find a significant hemispheric processing asymmetry in visuospatial categorical and coordinate tasks.

Cranial crassicaudiasis in two coastal dolphin species from South Africa is predominantly a disease of immature individuals

2020 ◽  
Vol 139 ◽  
pp. 93-102 ◽  
Author(s):  
MF Van Bressem ◽  
P Duignan ◽  
JA Raga ◽  
K Van Waerebeek ◽  
N Fraijia-Fernández ◽  
...  
Keyword(s):  
South Africa ◽  
Bone Development ◽  
Bottlenose Dolphins ◽  
Fatal Outcome ◽  
Population Level ◽  
Cape Coast ◽  
Osteolytic Lesions ◽  
Immune Mediated ◽  
Significant Difference ◽  
The Difference

Crassicauda spp. (Nematoda) infest the cranial sinuses of several odontocetes, causing diagnostic trabecular osteolytic lesions. We examined skulls of 77 Indian Ocean humpback dolphins Sousa plumbea and 69 Indo-Pacific bottlenose dolphins Tursiops aduncus, caught in bather-protecting nets off KwaZulu-Natal (KZN) from 1970-2017, and skulls of 6 S. plumbea stranded along the southern Cape coast in South Africa from 1963-2002. Prevalence of cranial crassicaudiasis was evaluated according to sex and cranial maturity. Overall, prevalence in S. plumbea and T. aduncus taken off KZN was 13 and 31.9%, respectively. Parasitosis variably affected 1 or more cranial bones (frontal, pterygoid, maxillary and sphenoid). No significant difference was found by gender for either species, allowing sexes to be pooled. However, there was a significant difference in lesion prevalence by age, with immature T. aduncus 4.6 times more likely affected than adults, while for S. plumbea, the difference was 6.5-fold. As severe osteolytic lesions are unlikely to heal without trace, we propose that infection is more likely to have a fatal outcome for immature dolphins, possibly because of incomplete bone development, lower immune competence in clearing parasites or an over-exuberant inflammatory response in concert with parasitic enzymatic erosion. Cranial osteolysis was not observed in mature males (18 S. plumbea, 21 T. aduncus), suggesting potential cohort-linked immune-mediated resistance to infestation. Crassicauda spp. may play a role in the natural mortality of S. plumbea and T. aduncus, but the pathogenesis and population level impact remain unknown.

scholarly journals Behavioral Triggers of Skin Conductance Responses and Their Neural Correlates in the Primate Amygdala

2009 ◽  
Vol 101 (4) ◽  
pp. 1749-1754 ◽  
Author(s):  
Christopher M. Laine ◽  
Kevin M. Spitler ◽  
Clayton P. Mosher ◽  
Katalin M. Gothard
Keyword(s):  
Skin Conductance ◽  
Single Unit ◽  
Population Level ◽  
Emotional Reaction ◽  
Neural Population ◽  
Experimental Conditions ◽  
Indirect Measure ◽  
Skin Conductance Responses ◽  
The Right ◽  
Sympathetic Arousal

The amygdala plays a crucial role in evaluating the emotional significance of stimuli and in transforming the results of this evaluation into appropriate autonomic responses. Lesion and stimulation studies suggest involvement of the amygdala in the generation of the skin conductance response (SCR), which is an indirect measure of autonomic activity that has been associated with both emotion and attention. It is unclear if this involvement marks an emotional reaction to an external stimulus or sympathetic arousal regardless of its origin. We recorded skin conductance in parallel with single-unit activity from the right amygdala of two rhesus monkeys during a rewarded image viewing task and while the monkeys sat alone in a dimly lit room, drifting in and out of sleep. In both experimental conditions, we found similar SCR-related modulation of activity at the single-unit and neural population level. This suggests that the amygdala contributes to the production or modulation of SCRs regardless of the source of sympathetic arousal.

Asymmetric superior oblique split Z-tendon lengthening for face turn in bilateral asymmetric superior oblique overaction and exotropia

2020 ◽  
pp. 112067211989798
Author(s):  
Massimiliano Serafino ◽  
Matteo Scaramuzzi ◽  
Claudia Specchia ◽  
Francesco Bonsignore ◽  
Paolo Nucci
Keyword(s):  
Oblique Muscle ◽  
Intermittent Exotropia ◽  
Left Turn ◽  
Vertical Deviation ◽  
Tendon Lengthening ◽  
The Face ◽  
The Right ◽  
Clinical Records ◽  
Superior Oblique Muscle ◽  
Superior Oblique

Introduction: The aim was to evaluate the effectiveness of the procedure of the superior oblique split Z-tendon lengthening to collapse A pattern and treat face turn in a cohort of patients with both incomitant intermittent exotropia and a vertical deviation associated with a bilateral asymmetric superior oblique overaction. Methods: We retrospectively reviewed the clinical records of patients with facial turn associated with intermittent exotropia and bilateral asymmetric superior oblique overaction, who underwent superior oblique muscle split tendon lengthening and concurrent horizontal surgery between 2009 and 2017. Results: A total of eight patients met the inclusion criteria. The preoperative average face turn was 26.8° (range, 20°–5°), and it significantly improved to 5.4° (range, 2°–8°) ( p < 0.05). All the patients showed an improvement in the face turn with neutralization of the vertical deviation. The vertical deviation in the right gaze for the patient with a right turn and the left gaze in patients with left turn improved significantly (values of p < 0.05). Conclusion: The superior oblique split Z-tendon lengthening was an effective procedure to collapse the A pattern and the treatment of the face turn in a cohort of patients with both incomitant intermittent exotropia and a vertical deviation associated with a bilateral asymmetric superior oblique muscle overaction with less complications, and less varying results.

scholarly journals Pubertal Testosterone Tracks the Developmental Trajectory of Neural Oscillatory Activity Serving Visuospatial Processing

2020 ◽  
Vol 30 (11) ◽  
pp. 5960-5971 ◽  
Author(s):  
Madison H Fung ◽  
Brittany K Taylor ◽  
Michaela R Frenzel ◽  
Jacob A Eastman ◽  
Yu-Ping Wang ◽  
...  
Keyword(s):  
Developmental Trajectory ◽  
Gamma Activity ◽  
Oscillatory Activity ◽  
Childhood And Adolescence ◽  
Oscillatory Dynamics ◽  
Gamma Range ◽  
Visuospatial Perception ◽  
Hormonal Fluctuations ◽  
Visuospatial Processing ◽  
The Right

Abstract Puberty is a period of substantial hormonal fluctuations that induce dramatic physical, neurological, and behavioral changes. Previous research has demonstrated that pubertal hormones modulate cortical development, as well as sex- and age-specific patterns of cognitive development during childhood and adolescence. However, the influence of pubertal hormones on the brain’s functional development, specifically neural oscillatory dynamics, has yet to be fully examined. Thus, in the current study, we used magnetoencephalography to investigate the oscillatory dynamics serving visuospatial perception and attention, and testosterone levels and chronological age as measures of development. Within a sample of typically developing youth, age was associated with changes in alpha, theta, and gamma oscillatory activity. Novel testosterone-by-sex interactions in the gamma range were identified in critical areas of the visual and attention networks. Females had increased gamma activity with increasing testosterone in the right temporal-parietal junction and occipital cortices, while males showed increased gamma activity in the right insula with increasing testosterone. These findings reveal robust developmental alterations in the oscillatory dynamics serving visuospatial processing during childhood and adolescence and provide novel insight into the hormonal basis of sexually dimorphic patterns of functional brain development during the pubertal transition that is at least partially mediated by endogenous testosterone.

Relation between Hemispheric Specialization and Gross Motor Control in Normal Right-Handed Children

1986 ◽  
Vol 63 (3) ◽  
pp. 1227-1231 ◽  
Author(s):  
Harriet Williams ◽  
Peter Werner ◽  
George Purgavie
Keyword(s):  
Cerebral Hemisphere ◽  
Hemispheric Specialization ◽  
Gross Motor ◽  
Projection System ◽  
Control Center ◽  
Left Cerebral Hemisphere ◽  
Processing Information ◽  
Hand Coordination ◽  
The Right ◽  
Abstract Shapes

The purpose of the present study was to investigate the nature of the relationship between gross-motor, eye-hand coordination and hemispheric specialization in normal right-handed children. Participants were 30 children, 75–99 mo. 15 boys and 15 girls performed a gross-motor eye-hand coordination task (a controlled, continuous one-handed ball bounce) and a test of hemispheric specialization. A backscreen tachistoscopic projection system was used to present letters and abstract shapes to left and right visual hemifields. A multivariate analysis of variance yielded a significant main effect for eye-hand coordination but not for sex. Follow-up analyses indicated that speed and accuracy of responses to verbal and spatial stimuli presented to the left cerebral hemisphere were significantly related to proficiency of eye-hand coordination. Data suggest that certain aspects of hemispheric specialization may be important to gross-motor eye-hand coordination in young children. Since the left cerebral hemisphere is the major control center for movements of the right side, the hemisphere which controls movements of a particular side may also assume the major responsibility for processing information needed to regulate those movements.

scholarly journals Smart wheelchair using android smartphone for physically disabled people

2018 ◽  
Vol 7 (2) ◽  
pp. 453 ◽  
Author(s):  
Siti Nur Suhaila Mirin ◽  
Khalil Azha Mohd Annuar ◽  
Chai Pui Yook
Keyword(s):  
Embedded System ◽  
Voice Recognition ◽  
Disabled People ◽  
Voice Input ◽  
Left Turn ◽  
Physically Disabled ◽  
The Right ◽  
Physically Disabled People ◽  
The Voice ◽  
Smart Wheelchair

This paper describes the development of a smart wheelchair system with voice recognition and touch controlled using an embedded system. An android application is developed and installed on the android smartphone. The system is divided into two main modes: voice recognition mode and touch mode. For the voice recognition mode, elderlies or physically disabled people (users) can provide the voice input, for example, “go”, “reverse”, “turn to the left”, “turn to the right” and “stop”. The wheelchair will move according to the command given. For the touch mode, the user can select the specified direction displayed within the four quadrants on the screen of the android smartphone to control the wheelchair. An Arduino Uno is used to execute all commands. The MD30C motor driver and HC05 Bluetooth module are used in this system. This system is designed to save time and energy of the user.

Hemispheric Specialization and Cognitive Development: Implications for Mathematics Education

1978 ◽  
Vol 9 (1) ◽  
pp. 20-32
Author(s):  
Grayson H. Wheatley ◽  
Robert Mitchell ◽  
Robert L. Frankland ◽  
Rosemarie Kraft
Keyword(s):  
Left Hemisphere ◽  
Hemispheric Asymmetry ◽  
Right Hemisphere ◽  
Mathematics Curriculum ◽  
Hemispheric Specialization ◽  
Brain Hemispheres ◽  
Spatial Tasks ◽  
Concrete Operational ◽  
The Right ◽  
Hemisphere Specialization

Evidence is presented for hemisphere specialization of the two brain hemispheres: the left hemisphere specialized for logico-analytic tasks and the right hemisphere, visuo-spatial tasks. A hypothesis is put forth for the emergence of the specialization that suggests a shift from predominant right hemisphere processing in infancy to predominant left hemisphere processing in adulthood. Results of the studies reviewed suggest the emergence of concrete-operational thought as the left hemisphere becomes capable of processing logical tasks. Electroencephalography seems particularly useful in determining specialization and mapping changes in hemispheric asymmetry. Implications for school mathematics curriculum are presented.

Hemispheric laterality and an evolutionary perspective

1981 ◽  
Vol 4 (1) ◽  
pp. 21-22 ◽  
Author(s):  
John L. Bradshaw
Keyword(s):  
Cognitive Deficit ◽  
Hemispheric Specialization ◽  
Physical Property ◽  
Population Level ◽  
Evolutionary Perspective ◽  
Specific Behavior ◽  
Evolutionary Advantage ◽  
The Individual ◽  
Species Specific ◽  
Prior State

Denenberg rightly stresses the importance of studying ethologically meaningful species-specific behavior in animals, and makes the interesting distinction between lateralization at an individual and at a population level. However, in the case of man, I believe Denenberg is wrong in arguing that lateralization in the individual increases with maturation. The overall evidence nowadays tends very much to the contrary. Moreover, with respect to a population, why should it become lateralized? If there is indeed an advantage for the individual in hemispheric specialization, why should the direction of such specialization be so consistent across a majority of individuals, whether human or, as Denenberg points out, other members of the phylum? Is there an evolutionary advantage in most animals' sharing the same direction, or is it a necessary consequence of some other preexisting, more fundamental anatomical, biochemical, or physical property of the organism and its constituents? If the former, why are not all members of the species, rather than just a majority, lateralized in the same direction? (Or, to put it another way, what is the evolutionary advantage to the species or individual of dimorphism, of retaining a minority who polarize in the opposite direction?) If the latter - i.e., if lateralization is a necessary consequence of some prior state - then there should not be any dimorphism, exceptions, or minority members, unless they are somehow disadvantaged in consequence. Indeed, there is some evidence of a cognitive deficit in sinistrals, though it is disputed (see Bradshaw 1980 for review), and others have even suggested that the species as a whole may benefit in some way from such an uneven dimorphism (Levy 1974), but what evidence is there for such propositions with respect to rats, apes, monkeys, or chicks? This is an issue that should be addressed in any general model that includes laterality in animals. [See Corhallis & Morgan: “On the Biological Basis of Human Laterality” BBS 1(2) 1978.]

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