Stereoscopic Vision Deficiency in Auditory-Deprived Children

Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 158-158
Author(s):  
M G Golubkov ◽  
N A Krasnoperova
Keyword(s):  
Spatial Vision ◽  
Stereoscopic Vision ◽  
Brightness Contrast ◽  
Contrast Threshold ◽  
Control Group ◽  
Visual Spatial ◽  
Spatial Mechanisms ◽  
Random Dot Stereograms ◽  
Auditory Systems ◽  
Deaf Persons

There is a widespread opinion that in deaf persons, on average, the visual system should be more highly developed than in people with normal hearing. However, one could also argue that normally the auditory system promotes the development and refinement of visual spatial mechanisms since localisation of many objects in the environment can be accomplished by visual and auditory systems simultaneously and, hence, can be done faster and more reliably. Because such supporting interactions in auditory-deprived children are absent or are weaker, one could expect slower or imperfect development of their spatial vision. We tried to test this hypothesis with the aid of a special test software (CLASS) allowing generation of random-dot stereograms (RDSs) in anaglyphic form (red - blue images). The varying parameters of RDSs were dot sizes (1 – 8 pixels) and brightness contrast of the blue image. The judgement about a subject's stereo vision was based on the presence of a stereo effect per se and on the brightness contrast threshold for the recognition of 3-D objects. The group of auditory-deprived children consisted of 70 subjects aged 3 – 9 years, the whole control group included 131 schoolchildren aged 7 – 9 years, but 87 subjects were only tested for the presence of a stereo-effect. The monocular visual acuity of all children was normal or corrected-to-normal. The results of testing by CLASS revealed significant visual deficiencies in auditory-deprived children: 10 (14%) were found to be stereo-blind, and 5 (7%) had markedly increased thresholds. In the control group, the percentage of stereo anomalies corresponded to the typical value of 2% – 4%: stereo-blindness was found in only 2 of all 131 children (the cases of strabismus and ptosis) and elevated thresholds were found in 2 children (out of 44).

Cognitive impairment in long-term benzodiazepine users

1988 ◽  
Vol 18 (2) ◽  
pp. 365-374 ◽  
Author(s):  
Susan Golombok ◽  
Parimala Moodley ◽  
Malcolm Lader
Keyword(s):  
Neuropsychological Tests ◽  
Matched Control ◽  
Control Group ◽  
Therapeutic Practice ◽  
The Past ◽  
Visual Spatial ◽  
Wide Range ◽  
High Doses ◽  
One Year

SynopsisIn view of the very extensive and often prolonged use of benzodiazepines in therapeutic practice, this study was designed to investigate whether or not cognitive ability is impaired in longterm benzodiazepine users, and to determine the nature and extent of any deficit. Fifty patients currently taking benzodiazepines for at least one year, thirty-four who had stopped taking benzodiazepines, and a matched control group of subjects who had never taken benzodiazepines or who had taken benzodiazepines in the past for less than one year were administered a battery of neuropsychological tests designed to measure a wide range of cognitive functions. It was found that patients taking high doses of benzodiazepines for long periods of time perform poorly on tasks involving visual-spatial ability and sustained attention. This is consistent with deficits in posterior cortical cognitive function.

scholarly journals Visual and previsual MRI-criteria for early diagnosis of cerebral small vessels disease in middle-aged patients: clinical and neuroimaging correlations

2021 ◽  
Vol 29 (3) ◽  
pp. 89-100
Author(s):  
О.V. Semonova ◽  
L.А. Myronyak ◽  
І.І. Glazovska ◽  
M.F. Ivanova ◽  
О.А. Krasyuk
Keyword(s):  
Early Diagnosis ◽  
Cerebrovascular Disorders ◽  
Total Duration ◽  
Multiparametric Mri ◽  
Control Group ◽  
Perivascular Spaces ◽  
Middle Aged ◽  
Aged Patients ◽  
Small Vessels ◽  
Visual Spatial

Background. The urgency of cerebral small vessel disease (cSVD) in modern neurology is considered mainly in terms of the development of vascular dementia and early diagnosis of Alzheimer’s disease. Minimal changes in MRI images and indistinct cognitive disorders in SNAMA-type cSVD (sporadic non-amyloid microangiopathy) last for a long time until they manifest as acute cerebrovascular disorders and/or significant mental deficits. However, clinical and neuroimaging criteria for early diagnosis of the disease have not been established yet, and the nature of the correlations between the indicators of neuropsychological and multiparametric MRI studies has not been clarified. Purpose – to develop criteria for early diagnosis of SNAMA cerebrovascular disease in middle-aged patients using neuropsychological studies and high-field multiparametric MRI. Materials and methods. The study enrolled 34 middle-aged patients (52.5 ± 10.8) with hypertension of stage 1–2, stage I–II and cSVD (women – 11 (32.4%), men – 23 (67.6%)). The control group (19 healthy individuals) was identical in age, gender and total duration of education. MRI (3T) was performed in the following modes: T1-2WI, DWI, 3D Brain FLAIR SHC, 3D tra, VEN BOLD, DTI medium iso SENSE. Neuropsychological studies were performed using the MoSA questionnaire evaluating the EIS, VIS, AIS, LIS, MIS, OIS domains. Results and discussion. We developed and introduced a modified scoring system for determining the severity of the burden of cerebral small vessels disease (BcSVDearly) in clinical practice. Among the early visual MRI markers, the expansion of the perivascular spaces was dominated in 27 (79.4%) of participants. A minor increase in Σ BcSVDearly to 6–7 points was found in 10 (29.4%) patients. The age norm (0–4 points) corresponded to the indicators of Σ BcSVDearly 23 out of 34 (67.6%) in the main group. Additional evidence of the disease was obtained by DTI MRI. The most significant decrease in FA was recorded in belt fibers (Δ: up to – 31.4%) and semioval centers (Δ: up to – 33.6%), the largest increase in MD was recorded in hooked bundles (Δ: up to 24.4%); right prefrontal, orbitofrontal and parietal areas (Δ up to 28.0%). According to the MoSA scale, moderate cognitive impairment was detected in 29 of 34 (85.3%) patients with a significant decrease in scores in the domains of EIS, VIS, LIS and AIS (p <0.001). The severity of early clinical manifestations of cSVD (non-amnestic polydomain moderate disorders of attention, speech, visual-spatial and executive cognitive functions) has been found to be moderately / markedly correlated with THMS, MD (positive) and FA (negative).Conclusions. We determined early visual signs of cSVD associated with arterial hypertension: dilated perivascular spaces, hyperintensity of the periventricular deep white matter of the brain, decrease by 9–33.6% of FA coefficient and increase by 20.8% – 28.0% MD. Moderate correlations between neuropsychological and neuroimaging studies have been demonstrated.

Altered Brain Activation in Military Personnel with One or More Traumatic Brain Injuries Following Blast

2011 ◽  
Vol 18 (1) ◽  
pp. 89-100 ◽  
Author(s):  
Randall S. Scheibel ◽  
Mary R. Newsome ◽  
Maya Troyanskaya ◽  
Xiaodi Lin ◽  
Joel L. Steinberg ◽  
...  
Keyword(s):  
Brain Injuries ◽  
Group Analysis ◽  
Negative Relationship ◽  
Brain Regions ◽  
Anterior Cingulate ◽  
Control Group ◽  
Post Traumatic Stress ◽  
Emotional Symptoms ◽  
Stimulus Response ◽  
Visual Spatial

AbstractExplosive blast is a frequent cause of traumatic brain injury (TBI) among personnel deployed to Afghanistan and Iraq. Functional magnetic resonance imaging (fMRI) with an event-related stimulus-response compatibility task was used to compare 15 subjects with mild, chronic blast-related TBI with 15 subjects who had not experienced a TBI or blast exposure during deployment. Six TBI subjects reported multiple injuries. Relative to the control group, TBI subjects had slightly slower responses during fMRI and increased somatic complaints and symptoms of post-traumatic stress disorder (PTSD) and depression. A between-group analysis indicated greater activation during stimulus-response incompatibility in TBI subjects within the anterior cingulate gyrus, medial frontal cortex, and posterior cerebral areas involved in visual and visual-spatial functions. This activation pattern was more extensive after statistically controlling for reaction time and symptoms of PTSD and depression. There was also a negative relationship between symptoms of PTSD and activation within posterior brain regions. These results provide evidence for increased task-related activation following mild, blast-related TBI and additional changes associated with emotional symptoms. Limitations of this study include no matching for combat exposure and different recruitment strategies so that the control group was largely a community-based sample, while many TBI subjects were seeking services. (JINS, 2012, 18, 89–100)

Neurophysiological Contributions to Luminance and Chromatic Mechanisms in a Hyperacuity Task

Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 339-339
Author(s):  
L Rüttiger ◽  
B B Lee
Keyword(s):  
Detection Threshold ◽  
Luminance Contrast ◽  
Contrast Threshold ◽  
Psychophysical Data ◽  
Spatial Mechanisms ◽  
Cone Cells

We recently reported (paper presented at ARVO 1997) psychophysical evidence as to contributions of luminance and chromatic mechanism in a hyperacuity task, namely detection of small displacements. Achromatic or chromatic (430, 550, 690 nm) edges were presented on white or chromatic (550 nm) backgrounds, and displacement thresholds measured as a function of luminance contrast. Above 3% (achromatic detection threshold), all conditions yielded nearly identical contrast/threshold curves; we believe a luminance mechanism to be responsible. In chromatic conditions, below 3% contrast, large (>100 s arc) displacements were detectable; presumably chromatic mechanisms are responsible. We have now carried out equivalent physiological experiments. Data were consistent with cells of the magnocellular (MC) pathway underlying the luminance mechanism. Opponent S-cone or parvocellular (PC) cells became responsive to displacements in the chromatic conditions. S-cone cells were very responsive to the 430 nm edge, and responded at low contrasts matching the psychophysical thresholds. L, M-cone opponent cells were responsive to the 690 nm edge, but less so than was expected from the psychophysical data. Our data suggest MC-cells underlie a luminance hyperacuity mechanism. Additional factors (eg cell numerosity) may have to be considered for chromatic spatial mechanisms.

Light-adaptation properties of the ultraviolet-sensitive cone mechanism in comparison to the other receptor mechanisms of goldfish

1991 ◽  
Vol 6 (4) ◽  
pp. 293-301 ◽  
Author(s):  
Craig W. Hawryshyn
Keyword(s):  
Heart Rate ◽  
Light Adaptation ◽  
Weber Fraction ◽  
Luminance Contrast ◽  
The Other ◽  
Brightness Contrast ◽  
Background Intensity ◽  
Contrast Threshold ◽  
Functional Differences ◽  
Threshold Technique

AbstractThe light-adaptation properties of goldfish photoreceptor mechanisms were examined using Stiles' two-color threshold technique. Threshold vs. background intensity (TVI) curves were determined for isolated cone and rod mechanisms using the heart-rate conditioning technique. The principal aim of this study was to compare the light-adaptation properties of the ultraviolet (UV)-sensitive cone mechanism to the other receptor mechanisms of goldfish. This examination revealed several striking functional differences: (1) The UV-sensitive cone mechanism threshold vs. background intensity (TVI) exhibited a slope of 0.65 (compared to the approximate 1.0 for the other cone mechanisms on a log/log plot) and thus was not in accordance with Weber's law. This may in part be related to the intrusion of the blue-sensitive mechanism at the upper radiance range. (2) The operation of the UV-sensitive cone mechanism was limited to intermediate intensities (i.e. not very dim or bright). (3) The UV-sensitive cone mechanism exhibited a Weber fraction or luminance contrast threshold of 0.316 that was approximately six times larger than the other cone mechanisms but comparable to the rod mechanism. This indicates that the UV-sensitive cone mechanism performs relatively poorly in terms of brightness contrast detection.

scholarly journals Foveal visual acuity is worse and shows stronger contour interaction effects for contrast-modulated than luminance-modulated Cs

2013 ◽  
Vol 30 (3) ◽  
pp. 105-120 ◽  
Author(s):  
MOHD IZZUDDIN HAIROL ◽  
MONIKA A. FORMANKIEWICZ ◽  
SARAH J. WAUGH
Keyword(s):  
Visual Acuity ◽  
Spatial Scales ◽  
Receptive Fields ◽  
Spatial Vision ◽  
Interaction Effects ◽  
Foveal Vision ◽  
Spatial Mechanisms ◽  
Visual Acuity Testing ◽  
Contour Interaction ◽  
Gap Width

AbstractContrast-modulated (CM) stimuli are processed by spatial mechanisms that operate at larger spatial scales than those processing luminance-modulated (LM) stimuli and may be more prone to deficits in developing, amblyopic, and aging visual systems. Understanding neural mechanisms of contour interaction or crowding will help in detecting disorders of spatial vision. In this study, contour interaction effects on visual acuity for LM and CM C and bar stimuli are assessed in normal foveal vision. In Experiment 1, visual acuity is measured for all-LM and all-CM stimuli, at ∼3.5× above their respective modulation thresholds. In Experiment 2, visual acuity is measured for Cs and bars of different type (LM C with CM bars and vice versa). Visual acuity is degraded for CM compared with LM Cs (0.46 ± 0.04 logMAR vs. 0.18 ± 0.04 logMAR). With nearby bars, CM acuity is degraded further (0.23 ± 0.01 logMAR or ∼2 lines on an acuity chart), significantly more than LM acuity (0.11 ± 0.01 logMAR, ∼1 line). Contour interaction for CM stimuli extends over greater distances (arcmin) than it does for LM stimuli, but extents are similar with respect to acuities (∼3.5× the C gap width). Contour interaction is evident when the Cs and bars are defined differently: it is stronger when an LM C is flanked by CM bars (0.17 ± 0.03 logMAR) than when a CM C is flanked by LM bars (0.08 ± 0.02 logMAR). Our results suggest that contour interaction for foveally viewed acuity stimuli involves feature integration, such that the outputs of receptive fields representing Cs and bars are combined. Contour interaction operates at LM and CM representational stages, it can occur across stage, and it is enhanced at the CM stage. Greater contour interaction for CM Cs and bars could hold value for visual acuity testing and earlier diagnosis of conditions for which crowding is important, such as in amblyopia.

Practice Variability and Longer and Short Retention Intervals

1982 ◽  
Vol 54 (1) ◽  
pp. 243-250 ◽  
Author(s):  
Robert Kerr
Keyword(s):  
Movement Control ◽  
Control Group ◽  
Practice Session ◽  
Knowledge Of Results ◽  
Practice Schedules ◽  
Visual Spatial ◽  
Single Target ◽  
Practice Variability ◽  
Distance Data ◽  
Retention Intervals

This experiment compared the effect of different practice schedules on distance and direction errors in a blindfolded two-dimensional movement. The three experimental groups, (a) criterion target only, (b) varied targets (not criterion), (c) single target (not criterion) and one control group (rested), were tested immediately after the “practice” session without knowledge of results and were tested again after a 1-wk. retention interval. The distance data demonstrated little difference among the three experimental groups, but all three groups were significantly better than the control group. However, there was little difference in errors of direction among the groups. While the data for distance support a schema interpretation of movement control, the data for direction appear to reflect the concept of a visual-spatial map being used to guide movements.

Hypnosis and learning: Pilot study on a group of students

2019 ◽  
Vol 17 (2) ◽  
Author(s):  
Coco Marinella ◽  
Ramaci Tiziana ◽  
Viola Giuseppe ◽  
Guglielmino Antonino ◽  
Giulia Di Gregorio ◽  
...  
Keyword(s):  
Spatial Memory ◽  
Control Group ◽  
Visual Spatial ◽  
Post War ◽  
The University ◽  
And Control ◽  
E Mail ◽  
Experimental Group ◽  
Corsi Test ◽  
Visual Spatial Memory

AbstractBackgroundMilton Erickson was the first to introduce hypnosis as a form of therapy during the post-war period. Numerous studies have evaluated the effects of hypnosis on memory, focusing principally on post-hypnotic amnesia, post-hypnotic hypermnesia, faux memories and learning growth.The aim of the present study was to determine if hypnosis can influence visual-spatial memory by increasing its performance and learning; to do this, we chose to utilise the Corsi Test (backward and forward).MethodsThree hundred second-year students enrolled in the psychology faculty at the University of Catania were informed of the research and its modalities, and an e-mail was sent to inquire if they wanted to participate in the experiment.Seventy female students took part in the research; 10 were excluded because they presented a high risk of being influenced under hypnosis.The 60 subjects in the research sample were randomly divided into two groups: the Experimental Group and Control Group.The protocol prescribed administration of the Corsi Test at Time 0 (start) followed by a resting phase of 30 min. The hypnotic state was subsequently introduced, and the Corsi Test was administered again.ResultsThe results of the Corsi Test for the Experimental Group showed statistically significant results (p<0.0004 and p<0.0001), while the results obtained in the Control Group did not show any significance.ConclusionsThese results led us to believe that hypnosis has the capacity to induce a nervous plasticity that supports learning of visual-spatial memory.

The Impact of Working Memory Training on Cognitive Abilities in Older Adults: The Role of Cognitive Reserve

2020 ◽  
Vol 13 (1) ◽  
pp. 52-61
Author(s):  
Sara Mičič ◽  
Marina Horvat ◽  
Karin Bakracevic
Keyword(s):  
Older Adults ◽  
Working Memory ◽  
Executive Functioning ◽  
Cognitive Abilities ◽  
Cognitive Reserve ◽  
Control Group ◽  
Visual Spatial ◽  
The Impact ◽  
Experimental Group

Objectives: The aims of this study were to determine whether Working Memory (WM) training improves the cognitive functioning of older adults and to determine the role of cognitive reserve in WM training. Method: Twenty-one older adults, aged between 65 and 91 years were included in the study. Ten of them were in the experimental group and 11 in the passive control group. The experimental group underwent 15 training sessions of n-back training over a period of five weeks, whereas the control group remained passive. All participants (from the experimental and control group) were tested before the training, one week after the training, and three months after the training with Rey– Osterrieth/Taylor Complex Figure test (ROCF), Digit span, and TMT (part A and part B). Results and Conclusion: Results of our study suggest that although the experimental group slightly improved their performance on the trained task, the progress was not statistically significant. There was also no statistically significant transfer of training effects onto tasks of visual-spatial and verbal memory, as well as those related to executive functioning. However, the study did identify a statistically significant correlation between cognitive reserve and certain tests performed at the final testing: tasks measuring executive functioning and spatial ability. Results also revealed that the group that showed improvement in the training task was significantly better in the ROCF test in comparison with the group that had not improved their performance on the N-back task. Thus, visual-spatial abilities (visual perception, construction, and memory) were more connected with success in WM training, than other measured cognitive abilities (e.g. verbal and numerical memory).

Early effect of thalamotomy on cognitive function in patients with Parkinson’s disease

2018 ◽  
Vol 14 (1) ◽  
Author(s):  
Edward J. Gorzelańczyk ◽  
Dorota Ackermann-Szulgit ◽  
Marek Kunc ◽  
Marek Harat ◽  
Piotr Walecki
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Cognitive Function ◽  
Verbal Memory ◽  
Spatial Working Memory ◽  
Verbal Learning ◽  
Control Group ◽  
Healthy Individuals ◽  
Early Effect ◽  
Visual Spatial

Abstract Thalamotomy is a neurosurgical procedure used in the treatment of advanced Parkinson’s disease (PD). The aim of our research is to evaluate the early impact of a lesion in the ventrointermedial nucleus (VIM) of the thalamus on cognitive and motor function in people with PD. Sixty patients who qualified for right- or left-sided VIM thalamotomy were involved in the study. The cognitive and motor functions of each patient were assessed both prior to and following the surgical procedure. Twenty-nine PD patients without ablative treatment were qualified for the comparison group, and 57 neurologically healthy individuals were assigned to the control group. The following tests were carried out: Mini Mental State Examination, Benton Visual Retention Test, Stroop Color and Word Test, Trail Making Test A&B, and Rey Auditory Verbal Learning Test. Statistically significant differences were found in reaction time, visual-spatial working memory, auditory-verbal memory, and overall level of cognitive function when comparing the results of tests carried out before and after thalamotomy and when comparing patients who had undergone surgery with untreated or healthy individuals. In patients with right-sided and left-sided thalamotomy differences were also found in the mean number of perseverative errors and recalled words.

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