Neural Markers Associated with the Temporal Deployment of Attention: A Systematic Review of Non-motor Psychophysical Measures Post-stroke

The focus of this research was not to come up with a solution to this problem but to describe the problem of attention. Thus this is totally useless for survivors.
This is where a great stroke association president would keep the research focus on solving all the problems in stroke, not just describing them.
http://journal.frontiersin.org/article/10.3389/fnhum.2017.00031/full?

Essie Low, Robin Laycock^† and Sheila Crewther^*

• Department of Psychology and Counselling, La Trobe University, Melbourne, VIC, Australia

In recent years, evidence has emerged to suggest abnormal temporal dynamics of attentional processing in stroke patients, especially those presenting with neglect symptoms. However, there has been little profiling of the nature and extent of such temporal anomalies. In addition, many paradigms currently used to measure the time required to deploy visual attention in stroke require a psychomotor response, and may therefore confound performance outcomes. Thus, the aim of this systematic review was to identify and evaluate studies that have employed non-motor psychophysical paradigms to characterize the temporal deployment of visual attention in space. A total of 13 non-motor psychophysical studies were identified, in which stimulus exposure times were manipulated to measure the time course of attentional deployment. Findings suggest that prolonged attentional deployment thresholds are more likely to occur with lesions within more ventral areas of the fronto-parietal network, irrespective of whether patients presented with neglect. Furthermore, this deficit was greater following right-hemispheric lesions, suggesting a dominant role for the right-hemisphere in facilitating efficient deployment of attention. These findings indicate that area and hemisphere of lesion may serve as putative markers of attentional deployment efficiency. In addition, findings also provide support for using non-motor psychophysical paradigms as a more rigorous approach to measuring and understanding the temporal dynamics of attention.

Study Aims

The focus of this systematic review was two-fold. Firstly, this review was aimed at investigating the degree to which temporal deployment of visual attention (i.e., the time course of attentional deployment) may be compromised post-stroke, and the neural markers associated with it. This aim would be addressed by exploring how performance on tasks were differentially affected by the following factors: (1) between patients with and without neglect; (2) between patients with lesions to different cerebral regions; and (3) between patients with lesions to different hemispheres, i.e., right-hemisphere damage (RHD) and left-hemisphere damage (LHD) patients.

In addition, this review aimed to identify studies that have employed non-motor psychophysical paradigms to characterize temporal deployment of attention following stroke. Identification of these studies was expected to provide knowledge of the extent to which non-motor contributions to performance are important in explaining temporal processing impairments. A list of common non-motor psychophysical paradigms and their associated methodologies is summarized in Table 1.