scholarly journals Hemispheric Asymmetries in Deaf and Hearing During Sustained Peripheral Selective Attention

2019 ◽  
Vol 25 (1) ◽  
pp. 1-9
Author(s):  
O Scott Gwinn ◽  
Fang Jiang

Abstract Previous studies have shown that compared to hearing individuals, early deaf individuals allocate relatively more attention to the periphery than central visual field. However, it is not clear whether these two groups also differ in their ability to selectively attend to specific peripheral locations. We examined deaf and hearing participants’ selective attention using electroencephalography (EEG) and a frequency tagging paradigm, in which participants attended to one of two peripheral displays of moving dots that changed directions at different rates. Both participant groups showed similar amplifications and reductions in the EEG signal at the attended and unattended frequencies, indicating similar control over their peripheral attention for motion stimuli. However, for deaf participants these effects were larger in a right hemispheric region of interest (ROI), while for hearing participants these effects were larger in a left ROI. These results contribute to a growing body of evidence for a right hemispheric processing advantage in deaf populations when attending to motion.

GeroPsych ◽  
2016 ◽  
Vol 29 (1) ◽  
pp. 29-36 ◽  
Author(s):  
Véronique Cornu ◽  
Jean-Paul Steinmetz ◽  
Carine Federspiel

Abstract. A growing body of research demonstrates an association between gait disorders, falls, and attentional capacities in older adults. The present work empirically analyzes differences in gait parameters in frail institutionalized older adults as a function of selective attention. Gait analysis under single- and dual-task conditions as well as selective attention measures were collected from a total of 33 nursing-home residents. We found that differences in selective attention performances were related to the investigated gait parameters. Poorer selective attention performances were associated with higher stride-to-stride variabilities and a slowing of gait speed under dual-task conditions. The present findings suggest a contribution of selective attention to a safe gait. Implications for gait rehabilitation programs are discussed.


2021 ◽  
Vol 223 ◽  
pp. 229-240
Author(s):  
Eren Ekici ◽  
Sasan Moghimi ◽  
Huiyuan Hou ◽  
James Proudfoot ◽  
Linda M. Zangwill ◽  
...  

1993 ◽  
Vol 10 (1) ◽  
pp. 159-171 ◽  
Author(s):  
Robert Desimone ◽  
Jeffrey Moran ◽  
Stanley J. Schein ◽  
Mortimer Mishkin

AbstractThe classically defined receptive fields of V4 cells are confined almost entirely to the contralateral visual field. However, these receptive fields are often surrounded by large, silent suppressive regions, and stimulating the surrounds can cause a complete suppression of response to a simultaneously presented stimulus within the receptive field. We investigated whether the suppressive surrounds might extend across the midline into the ipsilateral visual field and, if so, whether the surrounds were dependent on the corpus callosum, which has a widespread distribution in V4. We found that the surrounds of more than half of the cells tested in the central visual field representation of V4 crossed into the ipsilateral visual field, with some extending up to at least 16 deg from the vertical meridian. Much of this suppression from the ipsilateral field was mediated by the corpus callosum, as section of the callosum dramatically reduced both the strength and extent of the surrounds. There remained, however, some residual suppression that was not further reduced by addition of an anterior commissure lesion. Because the residual ipsilateral suppression was similar in magnitude and extent to that found following section of the optic tract contralateral to the V4 recording, we concluded that it was retinal in origin. Using the same techniques employed in V4, we also mapped the ipsilateral extent of surrounds in the foveal representation of VI in an intact monkey. Results were very similar to those in V4 following commissural or contralateral tract sections. The findings suggest that V4 is a central site for long-range interactions both within and across the two visual hemifields. Taken with previous work, the results are consistent with the notion that the large suppressive surrounds of V4 neurons contribute to the neural mechanisms of color constancy and figure-ground separation.


2007 ◽  
Vol 17 (4) ◽  
pp. 534-537 ◽  
Author(s):  
A. Perdicchi ◽  
M. Iester ◽  
G. Scuderi ◽  
S. Amodeo ◽  
E.M. Medori ◽  
...  

Purpose To make a visual field retrospective analysis on a group of patients with primary open angle glaucoma (POAG) and to evaluate whether different refractive errors could have different progression of the 30° central sensitivity. Methods A total of 110 patients with POAG (52 men and 58 women) were included in the study. All the patients were divided into four subgroups based on the refractive error. The visual field of all the included patients was assessed by an Octopus 30° central visual field every 6 months, for a total of 837 visual fields examined. The resulting data were analyzed by PERIDATA for Windows 1.7 TREND function. Mean defect (MD) and loss variance (LV) were considered for the analysis. Results At the first examination, 82% of eyes showed a global decrease of differential light sensitivity (MD >2 dB) and in 67% the distribution of the defect was nonhomogeneous (LV >6 dB). The analysis of variance for subgroups showed a more significant decrease of MD in highly myopic patients. A linear regression analysis highlighted a statistically significant change in time of MD in 36% and of LV in 34% of the eyes studied. Highly myopic patients had the highest (p<0.01) percentage of change of MD and LV (46% and 42%, respectively). Among the four subgroups, there was no difference in progression of MD decrease in time. Conclusions These results showed that after 5 years of glaucoma, the visual field was altered in most of the eyes examined (82%) and that in 67% of cases, its defect was nonhomogeneous and worsened with the increase of myopia. The regression linear analysis of visual field changes in time showed a progressive increase of MD and LV in approximately one third of all the eyes examined.


Author(s):  
Nevin W. El-Nimri ◽  
Rafaella C. Penteado ◽  
Christopher Bowd ◽  
James A. Proudfoot ◽  
Huiyuan Hou ◽  
...  

Author(s):  
Chaabane Djeraba ◽  
Adel Lablack ◽  
Yassine Benabbas

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