Rate Of Visual Processing Research Articles

Visual Information Processing in Young and Older Adults.

Decline in information processing with age is well-documented in the scientific literature. However, some discrepancy remains in relation to which cognitive domains are most susceptible to the aging process and which may remain intact. Furthermore, information processing has not been investigated nor considered as a function of affect, familiarity and complexity of tasks in a single experimental study. Thus, the current study investigated rate of visual information processing in 67 young university students (M age = 19.64 years) and 33 educated healthy older adults (M age = 70.33 years), while accounting for depression, anxiety and stress symptoms using the DASS. Rates of visual processing were measured as minimum time of stimulus exposure duration required for correct object recognition on a simple visual task [Inspection Time (IT)], and on a more complex visual cognitive task known as Change Detection (CD)] as well as words per minute on a text reading task (FastaReada). The results demonstrated significantly slower performance by older adults on the IT and CD, but comparable rates of text reading on a semantically more complex, but ecologically valid and familiar visual task that requires organized sequential shifts in attention via eye movements, continuous visual processing, access to working memory and semantic comprehension. The results also demonstrated that affective influences did not play a role in the older adults task performance, and that changes in cognitive domains may begin with older adults being slower to attend to and identify newly appearing familiar objects, as well as slower to encode and embed new information in memory during tasks that require a less practiced/familiar task strategy.

The visual attentional blink reflects constraints on temporal visual processing, not just a lapse of visual memory

Background: Most theories related to the attentional blink (AB), defined as the refractory period of 300 to 500-msecs following a conscious visual identification, during which a second detection task is impaired, argue that limitations of ‘visual working memory’ (VWM) underlie the phenomenon rather than suppression of attention. The current study examined the relationship between performance on an AB task and classical measures of visual and auditory memory and executive function (EF).Methods: Fifty‐one adult volunteers completed the AB task but only 27 of these also completed an extensive battery of traditional measures of short‐term and working memory, processing speed and EF. Correlation and regression methods were used to analyse the data.Results: Bivariate correlation showed a significant relationship between AB duration and non‐verbal intelligence and processing speed. Multiple regression analysis demonstrated that four factors (non‐verbal intelligence, letter‐number sequencing, visual search and visuo‐spatial recognition memory) explained 40 per cent of the variance, with better reasoning skills and letter‐number sequencing associated with a shorter AB, and better visuo‐spatial recognition memory associated with a longer AB.Conclusion: The positive beta weight in the model for visuo‐spatial recognition memory may reflect that the ability to later recall a target depends on its depth of encoding. On the other hand, the negative betas in the regression model for verbal intelligence and processing speed indicate that AB duration may be a potentially useful measure of temporal rate of visual processing. Finally, the lack of any relationship between the AB and executive function performance measures used suggests that the mechanism of the AB is primarily confined to early sensory processing and lower level working memory.

Backward Pattern Masking of Familiar and Unfamiliar Materials in Disabled and Normal Readers

A discrimination task involving backward pattern masking was designed to investigate differences between disabled and normal readers in text perception. Masking was observed for both groups with unfamiliar Japanese materials, but disabled readers were less sensitive in discriminating than were normal readers. The same result was obtained with Roman letters, despite the high familiarity of materials to both groups, and with nonwords and words. A significant interaction between group and stimulus onset asynchrony, indicating that disabled readers recovered from masking at a slower rate than normal readers, was found only with nonwords. Visual factors alone could not have mediated group differences. A subgroup of disabled readers, formed on the basis of susceptiblity to masking, showed evidence of a deficit in rate of visual processing. The results are likely due to differences in the quality of representations of visual information used in discrimination and in word recognition.