Developmental Changes in Visual Information Processing and Short-Term Visual Memory

Background:Cognitive impairments are considered a component of the extended clinical syndrome of schizophrenia. the aim of the current project was to investigate putative cognitive deficits in individuals with Early Onset Schizophrenia (EOS; defined herein as onset before the age of 18) and their relatives.Methods:53 EOS probands and 117 unaffected first-degree-relatives were examined on memory (Wechsler Memory Scale-Revised), verbal learning and recognition (California Verbal Learning Test), and attention (SPAN of apprehension test and degraded-stimulus continuous performance test (DS-CPT)). the Structured Clinical Interview for DSM-IV yielded four diagnostic groups: EOS probands; relatives with Mood Disorders; other Axis I diagnoses; and no diagnosis (healthy). Analysis of co-variance was performed with diagnosis as fixed factor and age as covariate.Results:EOS probands under performed on General Memory, Verbal Memory and Delayed Recall indices (WMS-R) compared to their relatives. both EOS and relatives with a mood disorder performed less well on Visual memory and Attention/Concentration indices [p< 0.001]. Relatives without Axis I diagnosis differentiated from EOS on all indices [p< 0.01]. Verbal learning and recognition impairments segregated in EOS and differentiated patients from their relatives. EOS probands and relatives with an Axis I diagnoses showed rapid visual information processing impairments (SPAN) compared to healthy relatives, while sustained attention (DS-CPT) remained relatively preserved in EOS and relatives.Conclusions:Genetic predisposition to schizophrenia may be mediated by visual information processing impairments, which differentiates healthy relatives from relatives with an Axis I diagnosis. Sustained attention seems to be a selective strength in EOS and relatives.

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Cognition, Object Formation, Speech Perception, Time Perception, Visual Attention, Visual Information Processing, Visual Memory

Perception & Psychophysics ◽

10.3758/app.71.1.3 ◽

2009 ◽

Vol 71 (1) ◽

pp. 3-4

Keyword(s):

Information Processing ◽

Speech Perception ◽

Visual Attention ◽

Time Perception ◽

Visual Information ◽

Visual Memory ◽

Visual Information Processing ◽

Perception Time

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Brief Visual Memory Processes in Reading-Disabled Children

South African Journal of Psychology ◽

10.1177/008124638201200102 ◽

1982 ◽

Vol 12 (1) ◽

pp. 7-18 ◽

Cited By ~ 1

Author(s):

Noleen Loubser ◽

Pamela Sharratt

Keyword(s):

Information Processing ◽

Visual Memory ◽

Backward Masking ◽

Disabled Children ◽

Short Term ◽

Memory Processes ◽

Memory Store ◽

Short Term Visual Memory ◽

Information Processing Approach ◽

Reading Disabled

The information processing approach was used as a basis for studying some brief visual memory processes in reading-disabled children. Three aspects of processing were examined, viz., (i) duration of icon persistence; (ii) performance under different backward masking conditions; and (iii) processing of information into a more durable short-term visual memory store. It was found that there were no differences in the duration of icon persistence in reading-disabled children, but that these children exhibited marked impairment in performance in the tasks used in the latter two experiments. The reasons for the reading-disabled children's poorer performance in these tasks were not apparent. Speculations about the strategies used by these children in approaching the tasks are made. Possible implications are discussed.

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Effects of Stimulus Duration, Temporal Delay, and Complexity on the Judgments of Dot Location

Perceptual and Motor Skills ◽

10.2466/pms.1996.82.2.459 ◽

1996 ◽

Vol 82 (2) ◽

pp. 459-466 ◽

Cited By ~ 1

Author(s):

Takashi Hanari

Keyword(s):

Information Processing ◽

Time Delay ◽

Visual Stimulus ◽

Delay Interval ◽

Visual Memory ◽

Early Stage ◽

Temporal Delay ◽

Short Term ◽

Short Term Visual Memory ◽

Masking Stimulus

The present study investigated how information on location was processed at an early stage of information processing by the task of recognizing dots presented briefly and followed by a masking stimulus. 8 subjects were asked on 1528 trials to recognize the positions of dots presented on a circumference. Effects of number of dots (1, 2, and 3), duration of presentation (36, 56, 200, and 500 msec.), and time delay (interval between the offset of display and the onset of recognition stimulus, 100 and 500 msec.) were examined. Analyses showed that the percentage of correct recognition increased with the duration of presentation and that the effect of duration decreased with the number of dots. Meanwhile, no significant effect was found for time delay. Consequently, with increased duration, the information on location is transferred to short-term visual memory. However, the ratio of transfer from iconic storage to short-term visual memory with duration varied with the complexity of visual stimulus.

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