Perception of Geometrical Figures in Persons with Damaged Temporal Lobes

Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 244-244
Author(s):  
R Lukauskiene ◽  
A Bertulis ◽  
I Busauskiene ◽  
B Mickiene
Keyword(s):  
Visual Field ◽  
Temporal Lobe ◽  
Spatial Neglect ◽  
Right Visual Field ◽  
Size Discrimination ◽  
Left Temporal Lobe ◽  
Form Discrimination ◽  
Temporal Lobes ◽  
The Right ◽  
Better Than

Persons with damaged temporal lobes were tested with computerised tests for size and form discrimination developed by A Bulatov and A Bertulis (1994 Perception23 Supplement, 25). 48 persons with damaged right and 54 persons with damaged left temporal lobe were tested. 8 persons showed hemineglect of the right visual field and 10 persons hemineglect of the left visual field. Posner (1987 Neuropsychologia25 135) stated that persons with unilateral spatial neglect had a specific inability to disengage their attention from a given object in order to reallocate it to another object positioned to its left or right. In our studies we determined whether size discrimination abnormalities also occur in the neglected side, opposite to the damaged temporal lobe. We estimated the accuracy with which subjects judged the height of two squares of different colours. Two squares with sizes varying from 0.2 to 3.0 deg were generated on the right and left side of the monitor. Subjects viewed the patterns binocularly at a distance of 1 m and adjusted the size of the square on the left to make its height equal to that on the right. The error of the setting was recorded. Persons with hemineglect of the visual field were unable to concentrate their attention at two figures located on both sides of the monitor so they were unable to make the comparison. Persons with right and left temporal lobe damage without hemineglect of the visual field judged the geometrical figures better than those with hemineglect but worse than controls. Persons with damaged left temporal lobe judged figures less well than persons with damaged right temporal lobe.

scholarly journals Exploring the Roles of Spectral Detail and Intonation Contour in Speech Intelligibility: An fMRI Study

2014 ◽  
Vol 26 (8) ◽  
pp. 1748-1763 ◽  
Author(s):  
Jeong S. Kyong ◽  
Sophie K. Scott ◽  
Stuart Rosen ◽  
Timothy B. Howe ◽  
Zarinah K. Agnew ◽  
...  
Keyword(s):  
Temporal Lobe ◽  
Speech Intelligibility ◽  
Pitch Contour ◽  
Speech Comprehension ◽  
Left Temporal Lobe ◽  
Temporal Lobes ◽  
Spectral Inversion ◽  
Pitch Information ◽  
Intelligible Speech ◽  
The Right

The melodic contour of speech forms an important perceptual aspect of tonal and nontonal languages and an important limiting factor on the intelligibility of speech heard through a cochlear implant. Previous work exploring the neural correlates of speech comprehension identified a left-dominant pathway in the temporal lobes supporting the extraction of an intelligible linguistic message, whereas the right anterior temporal lobe showed an overall preference for signals clearly conveying dynamic pitch information [Johnsrude, I. S., Penhune, V. B., & Zatorre, R. J. Functional specificity in the right human auditory cortex for perceiving pitch direction. Brain, 123, 155–163, 2000; Scott, S. K., Blank, C. C., Rosen, S., & Wise, R. J. Identification of a pathway for intelligible speech in the left temporal lobe. Brain, 123, 2400–2406, 2000]. The current study combined modulations of overall intelligibility (through vocoding and spectral inversion) with a manipulation of pitch contour (normal vs. falling) to investigate the processing of spoken sentences in functional MRI. Our overall findings replicate and extend those of Scott et al. [Scott, S. K., Blank, C. C., Rosen, S., & Wise, R. J. Identification of a pathway for intelligible speech in the left temporal lobe. Brain, 123, 2400–2406, 2000], where greater sentence intelligibility was predominately associated with increased activity in the left STS, and the greatest response to normal sentence melody was found in right superior temporal gyrus. These data suggest a spatial distinction between brain areas associated with intelligibility and those involved in the processing of dynamic pitch information in speech. By including a set of complexity-matched unintelligible conditions created by spectral inversion, this is additionally the first study reporting a fully factorial exploration of spectrotemporal complexity and spectral inversion as they relate to the neural processing of speech intelligibility. Perhaps surprisingly, there was little evidence for an interaction between the two factors—we discuss the implications for the processing of sound and speech in the dorsolateral temporal lobes.

scholarly journals Culture and Memory: Features of Recalling in Different Cultural Contexts

2017 ◽  
Vol 13 (4) ◽  
pp. 49-55
Author(s):  
V.N. Pavlenko
Keyword(s):  
Visual Field ◽  
Right Visual Field ◽  
Cross Cultural Study ◽  
Graphic Representations ◽  
Exposure Interval ◽  
Arab Students ◽  
The Difference ◽  
The Right ◽  
Different Cultures ◽  
Better Than

The paper presents outcomes of a cross-cultural study on the process of recalling in Arab (Moroccan) and Ukrainian students. The study aimed to explore the relation between recall and the place of the recalled material in the row (in particular, left or right visual field), the type of the stimuli (numbers, pictures, graphic representations, colours, images of people), and the time of exposition. The study revealed both similarities and differences in recalling in the students of different cultures. For instance, Moroccan students were generally better at recalling the material that was presented to them, and this was especially the case for the material that was placed in the right part of the visual field. Arab students were also far better than Ukrainian students at memorising most of the types of the stimuli (the difference was most obvious in recalling graphic material). However, this was not true for recalling people’s images: Ukrainian students were more successful with this task. The study also revealed that the exposure interval has a different impact on the effectiveness of recalling in representatives of the Arab (Moroccan) and Ukrainian cultures, which is especially striking in memorising numbers.

Object-Centered Attentional Biases in the Intact Brain

1996 ◽  
Vol 8 (6) ◽  
pp. 540-550 ◽  
Author(s):  
Patricia A. Reuter-Lorenz ◽  
Maxwell Drain ◽  
Corinne Hardy-Morais
Keyword(s):  
Visual Field ◽  
Right Visual Field ◽  
Normal Brain ◽  
Opposite Pattern ◽  
Intact Brain ◽  
Left And Right ◽  
The Right ◽  
Neurologically Intact ◽  
Patient Studies ◽  
Better Than

By simulating neglect-like effects in neurologically intact observers, we evaluated whether normal attentional allocation can be object centered. In a series of three experiments, observers detected a small gap on the left or right side of a configuration presented in either the left of right visual field. The figures were positioned so that on different trials, the left and right sides would fall in the same retinotopic, hemispatial, and environmental location. Thus, only the location with respect to an object-centered frame varied. We found opposite patterns of bias within each visual field: For figures in the left visual field, left gaps were detected better than right gaps, whereas in the right visual field the opposite pattern was evident. Control conditions indicate that these biases are not due to masking from eccentric contours and depend on the left and right segments being united into a single form. These results indicate that opposing orientational biases of the left and right hemispheres can operate within an object-centered frame in the normal brain. This evidence converges with patient studies and single-unit electrophysiology to reveal the importance of a relatively late, abstract locus for visual selection.

scholarly journals Orthographic neighbourhood effects during lateralised lexical decision are abolished with bilateral presentation

2021 ◽  
Author(s):  
Regan Mills ◽  
Zoe Victoria Joan Woodhead ◽  
Adam James Parker
Keyword(s):  
Visual Field ◽  
Visual Stimulation ◽  
Hemispheric Dominance ◽  
Right Visual Field ◽  
Neighbourhood Effects ◽  
Bilateral Presentation ◽  
Large N ◽  
The Right ◽  
A Minor ◽  
Better Than

Words presented to the right visual field (RVF) are processed more rapidly than those in the left visual field (LVF), presumably because of more direct links to the language dominant left cerebral hemisphere. This effect is moderated by a word’s orthographic neighbourhood size (N), with LVF facilitation and RVF inhibition for words with large N. Across two experiments, we sought to further examine lateralised N effects. Experiment 1 examined how hemispheric dominance for language influenced lateralised N effects, in 140 left-handers using a visual half-field task with bilateral presentation. Neither typically nor atypically lateralized participants showed the expected N effect, making the results ambiguous: it could be that left-handers fail to show N effects, or the effect could be abolished by some procedural aspect. Experiment 2 looked to test these options by testing 56 right-handers who responded to the same stimulus set under the original bilateral presentation condition and under unilateral presentation. N effects were found under unilateral but not bilateral presentation. We had adopted bilateral presentation because it had been recommended as better than unilateral presentation for controlling fixation and visual stimulation; our results indicate that this is not a minor methodological modification: it can dramatically affect lateralized effects.

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.

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