Categorical and coordinate visuospatial processing in younger and older adults

In this thesis, four experiments were conducted in which participants made a categorical or coordinate spatial relation judgement concerning the location of a dot in relation to a bar. The main aim was to investigate how, if at all, categorical and coordinate VS processes changed with older age. In addition, the importance of task demand and the underlying cognitive processes involved in categorical and coordinate VS judgements were also examined. In every experiment participants were faster and more accurate to make categorical visuospatial judgements than coordinate visuospatial judgements. This was taken to suggest that categorical visuospatial judgements are less demanding than coordinate visuospatial judgements. Younger adults were also found to process visuospatial information more quickly than older adults; however, accuracy rates and discrimination ability were similar. Furthermore, in contrast to expectation, coordinate visuospatial processes were not disproportionately affected by age-related decline. Processing of categorical and coordinate visuospatial judgements was found to be affected by the distance of the dot from the bar and by the visual field in which stimuli were presented. However, the inconsistent effects of visual field across experiments made interpretation of these findings difficult. Experiment 4 examined patterns of eye movements associated with categorical and coordinate visuospatial processes to gain insight into the underlying cognitive processes. The results indicated that visuospatial cognitive processing that occurs for above/below and near/far judgements is often qualitatively different from that which occurs when the task required precise distance estimation. In conclusion, the experiments presented in this thesis provide significant insight into the cognitive processes associated with categorical and coordinate visuospatial judgements.

Name dc:type.qualificationname

Ph.D.

Level dc:type.qualificationlevel

doctoral

Grantor dc:publisher.institution

University of Southampton

Year dc:date.issued

2009

Author dc:creator

• Meadmore, Katie

Advisor dc:contributor.advisor

• Liversedge, Simon P.