scholarly journals A Brief Exposure to Leftward Prismatic Adaptation Enhances the Representation of the Ipsilateral, Right Visual Field in the Right Inferior Parietal Lobule

eNeuro ◽  
2017 ◽  
Vol 4 (5) ◽  
pp. ENEURO.0310-17.2017 ◽  
Author(s):  
Sonia Crottaz-Herbette ◽  
Eleonora Fornari ◽  
Isabel Tissieres ◽  
Stephanie Clarke
Keyword(s):  
Visual Field ◽  
Right Visual Field ◽  
Inferior Parietal Lobule ◽  
Parietal Lobule ◽  
The Right ◽  
Prismatic Adaptation

scholarly journals Lateralization of attention in adults with ADHD: Evidence of pseudoneglect

2020 ◽  
Vol 63 (1) ◽  
Author(s):  
Bartosz Helfer ◽  
Stefanos Maltezos ◽  
Elizabeth Liddle ◽  
Jonna Kuntsi ◽  
Philip Asherson
Keyword(s):  
Reaction Time ◽  
Visual Field ◽  
Reaction Times ◽  
Study Participant ◽  
Reaction Time Task ◽  
Right Visual Field ◽  
Time Variability ◽  
Incentive Condition ◽  
Reaction Time Variability ◽  
The Right

Abstract Background. We investigated whether adults with attention-deficit/hyperactivity disorder (ADHD) show pseudoneglect—preferential allocation of attention to the left visual field (LVF) and a resulting slowing of mean reaction times (MRTs) in the right visual field (RVF), characteristic of neurotypical (NT) individuals —and whether lateralization of attention is modulated by presentation speed and incentives. Method. Fast Task, a four-choice reaction-time task where stimuli were presented in LVF or RVF, was used to investigate differences in MRT and reaction time variability (RTV) in adults with ADHD (n = 43) and NT adults (n = 46) between a slow/no-incentive and fast/incentive condition. In the lateralization analyses, pseudoneglect was assessed based on MRT, which was calculated separately for the LVF and RVF for each condition and each study participant. Results. Adults with ADHD had overall slower MRT and increased RTV relative to NT. MRT and RTV improved under the fast/incentive condition. Both groups showed RVF-slowing with no between-group or between-conditions differences in RVF-slowing. Conclusion. Adults with ADHD exhibited pseudoneglect, a NT pattern of lateralization of attention, which was not attenuated by presentation speed and incentives.

On the Relation between Visual Spatial Attention and Visual Field Asymmetries

1992 ◽  
Vol 44 (3) ◽  
pp. 529-555 ◽  
Author(s):  
T. A Mondor ◽  
M.P. Bryden
Keyword(s):  
Visual Field ◽  
Visual Attention ◽  
Visual Fields ◽  
Stimulus Onset ◽  
Right Visual Field ◽  
Structural Factors ◽  
Letter Identification ◽  
Functional Capabilities ◽  
Visual Spatial ◽  
The Right

In the typical visual laterality experiment, words and letters are more rapidly and accurately identified in the right visual field than in the left. However, while such studies usually control fixation, the deployment of visual attention is rarely restricted. The present studies investigated the influence of visual attention on the visual field asymmetries normally observed in single-letter identification and lexical decision tasks. Attention was controlled using a peripheral cue that provided advance knowledge of the location of the forthcoming stimulus. The time period between the onset of the cue and the onset of the stimulus (Stimulus Onset Asynchrony—SOA) was varied, such that the time available for attention to focus upon the location was controlled. At short SO As a right visual field advantage for identifying single letters and for making lexical decisions was apparent. However, at longer SOAs letters and words presented in the two visual fields were identified equally well. It is concluded that visual field advantages arise from an interaction of attentional and structural factors and that the attentional component in visual field asymmetries must be controlled in order to approximate more closely a true assessment of the relative functional capabilities of the right and left cerebral hemispheres.

scholarly journals Chronic (Rasmussen’s) Encephalitis in an Adult

2003 ◽  
Vol 30 (3) ◽  
pp. 263-265 ◽  
Author(s):  
Richard Wennberg ◽  
Sukriti Nag ◽  
Mary-Pat McAndrews ◽  
Andres M. Lozano ◽  
Richard Farb ◽  
...  
Keyword(s):  
Visual Field ◽  
Right Visual Field ◽  
Loss Of Consciousness ◽  
Mild Head Injury ◽  
Partial Seizures ◽  
Complex Partial Seizures ◽  
The Past ◽  
Rasmussen’S Encephalitis ◽  
The Face ◽  
The Right

A 24-year-old woman was referred because of incompletely-controlled complex partial seizures. Her seizures had started at age 21, after a mild head injury with brief loss of consciousness incurred in a biking accident, and were characterized by a sensation of bright flashing lights in the right visual field, followed by numbness and tingling in the right foot, spreading up the leg and to the arm, ultimately involving the entire right side, including the face. Occasionally they spread further to involve right facial twitching with jerking of the right arm and leg, loss of awareness and, at the onset of her epilepsy, rare secondarily generalized convulsions. Seizure frequency averaged three to four per month. She was initially treated with phenytoin and clobazam and subsequently changed to carbamazepine 800 milligrams per day. She also complained that her right side was no longer as strong as her left and that it was also numb, especially the leg, but felt that this weakness had stabilized or improved slightly over the past two years.

Lateral Onset Asynchrony in Left-Handers

1976 ◽  
Vol 43 (1) ◽  
pp. 255-259 ◽  
Author(s):  
Takeshi Hatta
Keyword(s):  
Visual Field ◽  
Standard Stimulus ◽  
The Other ◽  
Right Visual Field ◽  
Left Handed ◽  
The Right ◽  
Onset Asynchrony

Study of matching judgment was designed to demonstrate an effect of lateral onset asynchrony in left-handed subjects, 7 males and 8 females. Japanese Hirakana letters or random forms were presented to one visual field first and to the other visual field second. 15 left-handers were requested to judge whether the successively presented stimuli were “same” or “different.” The results showed that for both types of stimuli there are no differences in accuracy of matching judgment whether the standard stimulus was presented to the right visual field first or to the left. These results indicate that the left-handed subjects may have a tendency toward hemispheric equi-potentiality for recognition of both verbal and non-verbal materials.

scholarly journals Effect of tDCS over the Right Inferior Parietal Lobule on Mind-Wandering Propensity

2020 ◽  
Author(s):  
Sean Coulborn ◽  
Howard Bowman ◽  
Chris Miall ◽  
Davinia Fernández-Espejo
Keyword(s):  
Mind Wandering ◽  
Inferior Parietal Lobule ◽  
Double Blind ◽  
Default Mode ◽  
Dorsolateral Prefrontal ◽  
Parietal Lobule ◽  
Response Task ◽  
Thought Probes ◽  
The Right ◽  
Subjective Reports

Mind-wandering is associated with switching our attention to internally directed thoughts and is by definition an intrinsic, self-generated cognitive function. Interestingly, previous research showed that it may be possible to modulate its propensity externally, with transcranial direct current stimulation (tDCS) targeting different regions in the default mode and executive control networks. However, these studies used highly heterogeneous montages (targeting the dorsolateral prefrontal cortex (DLPFC), the right inferior parietal lobule (IPL), or both concurrently), often showed contradicting results, and in many cases failed to replicate. Our study aimed to establish whether tDCS of the default mode network, via targeting the right IPL alone, could modulate mind-wandering propensity using a within-subjects double-blind, counterbalanced design. Participants completed a sustained attention to response task (SART) interspersed with thought-probes to capture their subjective reports of mind-wandering before and after receiving anodal, cathodal, or sham tDCS over the right IPL (with the reference over the left cheek). We found evidence for the lack of an effect of stimulation on subjective reports of mind-wandering (JZS-BF01 = 5.19), as well as on performance on the SART task (errors (JZS-BF01 = 6.79) and reaction time (JZS-BF01 = 5.94). Overall, we failed to replicate previous reports of successful modulations of mind-wandering propensity with tDCS over the IPL, instead providing evidence in support of the lack of an effect. This, and other recent unsuccessful replications call into question whether it is indeed possible to externally modulate spontaneous or self-generated cognitive processes.

Lateral Asymmetry in Visual Detection under Hypnosis

1987 ◽  
Vol 65 (3) ◽  
pp. 899-906 ◽  
Author(s):  
Edward J. Hass ◽  
Christopher W. Holden
Keyword(s):  
Visual Field ◽  
Response Time ◽  
Left Visual Field ◽  
Priming Effect ◽  
Visual Detection ◽  
Dependent Measure ◽  
Right Visual Field ◽  
Lateral Asymmetry ◽  
Control Subjects ◽  
The Right

It has been suggested that the hypnotic state results in a greater relative activation or priming of the right cerebral hemisphere than of the left hemisphere. The experiment reported here employed hypnosis to produce such a priming effect in a visual-detection task. Subjects were required to detect the presence or absence of a gap in outline squares presented either to the left visual field or right visual field, with response time as the primary dependent measure. Those subjects who were hypnotized produced a 50-msec. response time difference favoring squares presented to the left visual field whereas control subjects and simulator-control subjects showed no lateral asymmetries. The result is classified as a material-nonspecific priming effect and discussed with regard to the nature of processing resources.

Interocular torsional disparity and visual cortical development in the cat

1990 ◽  
Vol 64 (4) ◽  
pp. 1352-1360 ◽  
Author(s):  
M. R. Isley ◽  
D. C. Rogers-Ramachandran ◽  
P. G. Shinkman
Keyword(s):  
Visual Cortex ◽  
Visual Field ◽  
Ocular Dominance ◽  
Visual Fields ◽  
Receptive Fields ◽  
Right Visual Field ◽  
Orientation Columns ◽  
Areas 17 And 18 ◽  
The Right ◽  
Visual Cortical

1. The present experiments were designed to assess the effects of relatively large optically induced interocular torsional disparities on the developing kitten visual cortex. Kittens were reared with restricted visual experience. Three groups viewed a normal visual environment through goggles fitted with small prisms that introduced torsional disparities between the left and right eyes' visual fields, equal but opposite in the two eyes. Kittens in the +32 degrees goggle rearing condition experienced a 16 degrees counterclockwise rotation of the left visual field and a 16 degrees clockwise rotation of the right visual field; in the -32 degrees goggle condition the rotations were clockwise in the left eye and counterclockwise in the right. In the control (0 degree) goggle condition, the prisms did not rotate the visual fields. Three additional groups viewed high-contrast square-wave gratings through Polaroid filters arranged to provide a constant 32 degrees of interocular orientation disparity. 2. Recordings were made from neurons in visual cortex around the border of areas 17 and 18 in all kittens. Development of cortical ocular dominance columns was severely disrupted in all the experimental (rotated) rearing conditions. Most cells were classified in the extreme ocular dominance categories 1, 2, 6, and 7. Development of the system of orientation columns was also affected: among the relatively few cells with oriented receptive fields in both eyes, the distributions of interocular disparities in preferred stimulus orientation were centered near 0 degree but showed significantly larger variances than in the control condition.(ABSTRACT TRUNCATED AT 250 WORDS)

Visual Masking, Handedness, and Laterality

1974 ◽  
Vol 38 (3) ◽  
pp. 803-811 ◽  
Author(s):  
S. M. Luria
Keyword(s):  
Visual Field ◽  
Left Visual Field ◽  
Visual Masking ◽  
Right Visual Field ◽  
Black Disk ◽  
Left Handed ◽  
Masking Stimulus ◽  
The Right

Monocular thresholds for a black disk and for single letters, presented either alone or followed by a masking stimulus, were obtained for both eyes of 16 left-handed Ss and 16 right-handed Ss. Thresholds for the disk tended to be lower when it was presented to the right visual field, particularly for the left eye and for right-handers. Thresholds for the letters tended to be lower when presented to the right visual field of right-handers and to the left visual field of left-handers. The masking stimulus enhanced these differences for the disk but not for the letters.

Sign in / Sign up

Export Citation Format

Share Document