Visual field processing in paranoid and non-paranoid schizophrenics

1993 ◽  
Vol 8 (6) ◽  
pp. 301-307 ◽  
Author(s):  
E Aharonovich ◽  
N Karny ◽  
I Nachson
Keyword(s):  
Visual Field ◽  
Left Hemisphere ◽  
Left Visual Field ◽  
Right Hemisphere ◽  
Paranoid Schizophrenia ◽  
Visual Fields ◽  
Auditory Modality ◽  
Right Hemisphere Dysfunction ◽  
The Right ◽  
Normal Controls

SummaryThe hypothesis that paranoid and non-paranoid schizophrenics are differentially associated with unilateral hemisphere dysfunction was tested on 12 paranoid and 12 non-paranoid schizophrenics, as well as on 24 affective patients and 24 normal controls. The subjects were presented for 150 ms with series of digit-pairs and open rings to the left or right visual fields. Overall recognition of digits and localization of gaps in the rings were better for the right than for the left visual field. However, performance of the paranoid and non-paranoid schizophrenics was relatively poorer in response to the right and left visual field stimuli, respectively. Since these data do not correspond to the findings obtained in the auditory modality, they were interpreted as indicating modality-specific associations of paranoid schizophrenia with left hemisphere dysfunction, and of non-paranoid schizophrenia with right hemisphere dysfunction.

Right Hemisphere Memory Bias Does Not Extend to Involuntary Memories for Negative Scenes

Perception ◽  
2021 ◽  
Vol 50 (1) ◽  
pp. 27-38
Author(s):  
Ella K. Moeck ◽  
Nicole A. Thomas ◽  
Melanie K. T. Takarangi
Keyword(s):  
Visual Field ◽  
Left Hemisphere ◽  
Right Hemisphere ◽  
Visual Fields ◽  
Memory Bias ◽  
Right Visual Field ◽  
Hemispheric Differences ◽  
Involuntary Memory ◽  
Involuntary Memories ◽  
The Right

Attention is unequally distributed across the visual field. Due to greater right than left hemisphere activation for visuospatial attention, people attend slightly more to the left than the right side. As a result, people voluntarily remember visual stimuli better when it first appears in the left than the right visual field. But does this effect—termed a right hemisphere memory bias—also enhance involuntary memory? We manipulated the presentation location of 100 highly negative images (chosen to increase the likelihood that participants would experience any involuntary memories) in three conditions: predominantly leftward (right hemisphere bias), predominantly rightward (left hemisphere bias), or equally in both visual fields (bilateral). We measured subsequent involuntary memories immediately and for 3 days after encoding. Contrary to predictions, biased hemispheric processing did not affect short- or long-term involuntary memory frequency or duration. Future research should measure hemispheric differences at retrieval, rather than just encoding.

Differential Visual Field-Interhemispheric Transfer: Can it Explain Sex and Handedness Differences in Lateralization?

1987 ◽  
Vol 65 (2) ◽  
pp. 423-429 ◽  
Author(s):  
Richard H. Haude ◽  
Mary Morrow-Tlucak ◽  
Diane M. Fox ◽  
Kevin B. Pickard
Keyword(s):  
Visual Field ◽  
Left Hemisphere ◽  
Left Visual Field ◽  
Spatial Information ◽  
Right Hemisphere ◽  
Right Visual Field ◽  
Localization Task ◽  
Left Handed ◽  
Functional Lateralization ◽  
The Right

104 men and women were tested for visual field-hemispheric transfer of spatial information on a dot-localization task. Right-handed subjects showed significant improvement when stimuli were presented to the left visual field of the right hemisphere (LVF-RH) after practice on the same task presented to the right visual field of the left hemisphere (RVF-LH) first. No improvement was found when the task was presented in the reverse order (LVF-RH first followed by RVF-LH). It was concluded that, for right-handers, transfer of spatial information to the right hemisphere is facilitated while transfer to the left hemisphere is inhibited. Left-handed subjects demonstrated no significant improvement in either condition, suggesting inhibition or lack of transfer of spatial information in either direction. No sex differences were found in either right-handed or left-handed subjects. The findings suggest that there may be different mechanisms underlying the similarities in functional lateralization of women and left-handers.

scholarly journals Low-frequency electroencephalogram oscillations govern left-eye lateralization during anti-predatory responses in the music frog

2020 ◽  
Vol 223 (21) ◽  
pp. jeb232637
Author(s):  
Jiangyan Shen ◽  
Ke Fang ◽  
Ping Liu ◽  
Yanzhu Fan ◽  
Jing Yang ◽  
...  
Keyword(s):  
Visual Field ◽  
Left Visual Field ◽  
Right Hemisphere ◽  
Brain Area ◽  
Power Spectra ◽  
Low Frequency ◽  
The Right ◽  
Electroencephalogram Eeg ◽  
The Brain ◽  
Steady Velocity

ABSTRACTVisual lateralization is widespread for prey and anti-predation in numerous taxa. However, it is still unknown how the brain governs this asymmetry. In this study, we conducted behavioral and electrophysiological experiments to evaluate anti-predatory behaviors and dynamic brain activities in Emei music frogs (Nidirana daunchina), to explore the potential eye bias for anti-predation and the underlying neural mechanisms. To do this, predator stimuli (a model snake head and a leaf as a control) were moved around the subjects in clockwise and anti-clockwise directions at steady velocity. We counted the number of anti-predatory responses and measured electroencephalogram (EEG) power spectra for each band and brain area (telencephalon, diencephalon and mesencephalon). Our results showed that (1) no significant eye preferences could be found for the control (leaf); however, the laterality index was significantly lower than zero when the predator stimulus was moved anti-clockwise, suggesting that left-eye advantage exists in this species for anti-predation; (2) compared with no stimulus in the visual field, the power spectra of delta and alpha bands were significantly greater when the predator stimulus was moved into the left visual field anti-clockwise; and, (3) generally, the power spectra of each band in the right-hemisphere for the left visual field were higher than those in the left counterpart. These results support that the left eye mediates the monitoring of a predator in music frogs and lower-frequency EEG oscillations govern this visual lateralization.

scholarly journals Visuospatial Attention and the Split Brain

Physiology ◽  
1997 ◽  
Vol 12 (5) ◽  
pp. 226-231
Author(s):  
G Berlucchi ◽  
GR Mangun ◽  
MS Gazzaniga
Keyword(s):  
Visual Field ◽  
Left Hemisphere ◽  
Right Hemisphere ◽  
Visuospatial Attention ◽  
Attentional Biases ◽  
Split Brain ◽  
Right Hemisphere Damage ◽  
Entire Visual Field ◽  
The Right

In callosotomy patients, the right hemisphere attends to the entire visual field, whereas the left hemisphere attends to the right field only. The occurence of rightward attentional biases, simulating a hemineglect from right hemisphere damage, suggests that in these patients visuospatial attention tends to be controlled by the left hemisphere.

Vocal Reaction Times to Tachistoscopically Presented High- and Low-Frequency Verbs: Some Evidence for Selective Minor Hemisphere Linguistic Analysis

1988 ◽  
Vol 66 (3) ◽  
pp. 803-810 ◽  
Author(s):  
Michael P. Rastatter ◽  
Catherine Loren
Keyword(s):  
Visual Field ◽  
High Frequency ◽  
Right Hemisphere ◽  
Visual Fields ◽  
Reaction Times ◽  
Low Frequency ◽  
Normal Subjects ◽  
Right Visual Field ◽  
Intact Brain ◽  
The Right

The current study investigated the capacity of the right hemisphere to process verbs using a paradigm proven reliable for predicting differential, minor hemisphere lexical analysis in the normal, intact brain. Vocal reaction times of normal subjects were measured to unilaterally presented verbs of high and of low frequency. A significant interaction was noted between the stimulus items and visual fields. Post hoc tests showed that vocal reaction times to verbs of high frequency were significantly faster following right visual-field presentations (right hemisphere). No significant differences in vocal reaction time occurred between the two visual fields for the verbs of low frequency. Also, significant differences were observed between the two types of verbs following left visual-field presentation but not the right. These results were interpreted to suggest that right-hemispheric analysis was restricted to the verbs of high frequency in the presence of a dominant left hemisphere.

Visual Field Sensitivity on a Two-Choice Discrimination Task

1981 ◽  
Vol 53 (1) ◽  
pp. 91-100 ◽  
Author(s):  
Paul Salmon ◽  
Albert Rodwan
Keyword(s):  
Visual Field ◽  
Signal Detection ◽  
Left Visual Field ◽  
Discrimination Task ◽  
Visual Fields ◽  
Detection Analysis ◽  
Field Sensitivity ◽  
Signal Detection Analysis ◽  
The Right ◽  
Stimulation Of

A signal-detection analysis was used to evaluate visual-field sensitivity on a two-choice (same/different) discrimination task. Pairs of unfamiliar geometrical forms were presented tachistoscopically to the right or left visual fields of 12 subjects. Of 12 subjects 11 obtained left visual-field values which exceeded those of the right. The data suggested that the superiority of stimulation of the left visual field resulted from greater sensitivity to “same” figure pairs.

Effect of Learning on Hemispheric Dominance and Free Recall in a Single Subject

1972 ◽  
Vol 31 (1) ◽  
pp. 227-230 ◽  
Author(s):  
Lester C. Shine ◽  
Joseph Wiant ◽  
Frank Da Polito
Keyword(s):  
Free Recall ◽  
Visual Field ◽  
Analysis Of Variance ◽  
Field Condition ◽  
Left Visual Field ◽  
Visual Fields ◽  
Hemispheric Dominance ◽  
Right Visual Field ◽  
Single Subject ◽  
The Right

This experiment was designed to investigate the effect of learning on the free recall of letters presented tachistoscopically either to the left visual field, the right visual field, or identically and simultaneously to both visual fields. A modified Shine-Bower analysis of variance was used to analyze S's performance. The results indicate that initially, in accord with previous research, the right visual field is superior to the left visual field in performance, but that this superiority tends to reduce across trials and practically disappears in the later trials. Also, the right visual field condition is not appreciably better in performance than the condition with both visual fields.

scholarly journals Single-Case Neuropsychological Assessment of a Patient with a Posterior Parietal Lesion Using Behavioral Testing and Resting-State fMRI

2021 ◽  
Vol 05 (03) ◽  
pp. 1-1
Author(s):  
Elisa Martín-Arévalo ◽  
◽  
Carole Guedj ◽  
François Cotton ◽  
Gilles Rode ◽  
...  
Keyword(s):  
Visual Field ◽  
Functional Connectivity ◽  
Resting State ◽  
Left Visual Field ◽  
Single Case ◽  
Visual Fields ◽  
Resting State Fmri ◽  
Occipital Area ◽  
Posterior Parietal ◽  
The Right

This study integrated functional connectivity measures using resting-state fMRI and behavioral data from a single-case observation of patient (PER) one year after right-hemispheric hemorrhage in the intraparietal sulcus and superior parietal lobule (IPS/SPL). PER showed no sign of clinical neglect. Her behavioral performance in the visuo-manual pointing task and in the letter discrimination task under conditions of endogenous and exogenous attentional cueing was compared between the left (affected) and right (unaffected/control) peripheral visual fields. The resting-state fMRI demonstrated an imbalance between the right and left hemispheric frontoparietal functional connectivity within the dorsal attentional and motor networks. Although the frontal and occipital cortices were not structurally damaged, specific fronto-occipital functional connectivity was imbalanced, which was strongly associated with the behavioral changes. First, the activity in the right frontal eye field showed weaker correlations with the activity in the right inferior occipital area compared to the correlation with the activity in the left inferior occipital area. This imbalanced fronto-occipital functional connectivity was accompanied by a specific impairment in endogenous covert attention in the left visual field. Second, the activity within M1 in both hemispheres showed weaker correlations with the activity of the right cuneus compared to the correlation with the activity in the left cuneus. The imbalanced fronto-occipital functional connectivity was associated with the impairment of the reaching movement of the left and right hands towards the left visual field (optic ataxia). Altogether, our results showed that a lesion to the posterior parietal cortex affects the relationship between distal regions underlying the sensorimotor and attentional abilities

Cerebral Lateralization of Global-Local Processing in Left- and Right-Handed People

2005 ◽  
Vol 100 (3) ◽  
pp. 734-742 ◽  
Author(s):  
Mohammad Ali Goodarzi ◽  
Mohammad Reza Taghavi ◽  
Mohammad Reza Zoughi
Keyword(s):  
Visual Field ◽  
Left Visual Field ◽  
Right Hemisphere ◽  
Local Processing ◽  
Cerebral Lateralization ◽  
Left Handed ◽  
Left And Right ◽  
The Right ◽  
Paradigm Analysis ◽  
Local Superiority

Cerebral lateralization of global-local processing of 70 left-handed and 70 right-handed students was compared using a computerized global-local task in a half-visual field paradigm. Analysis showed that left-handed individuals were slower than right-handed individuals in processing Globally Directed stimuli presented to the left visual field (right hemisphere). In addition, left-handed individuals showed smaller local superiority in the left hemisphere to the right-handed individuals. These findings are more consistent with Levy's prediction of spatial inferiority of left-handed individuals than Geschwind and Galaburda's or Annett's hypotheses.

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