A Review of Divided Attention Dysfunction in Alzheimer’s Disease

Divided attention is impaired in the early stages of Alzheimer’s disease (AD). The influence of divided attention on people with AD has been considered from different perspectives, such as motor ability, cortical responses, performance in divided attention evaluation tasks, and comparison of divided attention and directed and focused attention. The purpose of the current study was to investigate divided attention in AD patients from these different perspectives.

 An electronic search was performed in January and February 2016 in PubMed, Science Direct, Medline, Scopus, Google Scholar, and Ovid databases to obtain relevant articles published from 1980 to 2015. The keywords used included “Alzheimer’s disease”, “attention”, and “divided attention”. The articles obtained were studied using the following standard protocol for inclusion criteria written in the English language, the focus of studies was on divided attention in AD, and no other types of cognitive ability. From the 60 articles found, 10 articles that were adhered to the inclusion criteria were selected for consideration.

The 10 studies reviewed considered divided attention in AD from different domains. These domains showed that AD patients had impaired performance in tasks that required divided attention and showed deficits in motor tasks stemming from the negative effects of impaired divided attention on motor ability. Different types of brain deficits have been observed in neuroimaging techniques in individuals with AD during divided attention tasks. Those with AD showed greater impairment for divided attention than for directed and focused attention.

Divided attention influences the lives of those with AD from several perspectives. These include the inability to focus on two or several relevant stimuli simultaneously that require divided attention rather than directed and focused attention and a deficit in the performance of motor tasks such as gait and other problems in daily life, such as falling. In addition, depression also had a negative effect on divided attention. Depressed AD patients had more difficulty in daily activities than AD patients without depression. The areas of the brain involved in divided attention in individuals with AD differ from those involved in unaffected people.