Gaze detection and gaze cuing in Alzheimer's disease.

People with Alzheimer's disease (AD) show problems with social processing in tasks which require the understanding of others' mental states. However traditional social processing tasks are cognitively complex, which may influence the effects of AD. Less is known about how AD influences more basic aspects of social perception, such as the ability to decode eye gaze direction or follow the gaze of another. The current research assessed whether those with AD showed difficulty in both explicitly decoding subtle manipulations of gaze direction (Study 1), and reflexively following another's eye gaze (Study 2). Those with AD were more impaired than a matched control group when making explicit discrimination distinctions between direct and averted gaze. In contrast people with Alzheimer's disease performed comparably to a control group when following gaze. This pattern indicates that more automatic aspects of social perception such as gaze following are unaffected by AD. In contrast, more controlled processes such as deciding whether someone is looking towards you are impaired in AD. This has implications for socially engaging with other people and interpreting their focus of interest.

Specificity of Age-Related Differences in Eye-Gaze Following: Evidence From Social and Nonsocial Stimuli.

BACKGROUND: Eye-gaze following is a fundamental social skill, facilitating communication. The present series of studies explored adult age-related differences in this key social-cognitive ability. METHOD: In Study 1 younger and older adult participants completed a cueing task in which eye-gaze cues were predictive or non-predictive of target location. Another eye-gaze cueing task, assessing the influence of congruent and incongruent eye-gaze cues relative to trials which provided no cue to target location, was administered in Study 2. Finally, in Study 3 the eye-gaze cue was replaced by an arrow. RESULTS: In Study 1 older adults showed less evidence of gaze following than younger participants when required to strategically follow predictive eye-gaze cues and when making automatic shifts of attention to non-predictive eye-gaze cues. Findings from Study 2 suggested that, unlike younger adults, older participants showed no facilitation effect and thus did not follow congruent eye-gaze cues. They also had significantly weaker attentional costs than their younger counterparts. These age-related differences were not found in the non-social arrow cueing task. DISCUSSION: Taken together these findings suggest older adults do not use eye-gaze cues to engage in joint attention, and have specific social difficulties decoding critical information from the eye region.

Adult aging, processing style, and the perception of biological motion.

UNLABELLED: BACKGROUND/STUDY CONTEXT: Social perception may be influenced by the extent to which individuals focus on global, rather than local, detail-based, processing of information about others. Here the authors investigated whether global processing biases relate to successful detection of actions and emotions from point-light biological motion (BM) stimuli. Also explored is whether age differences in BM perception and global-local processing biases are related. METHODS: One hundred and twenty-seven participants (aged 18 to 86) completed tasks assessing BM perception and global-local processing. RESULTS: Successful decoding of actions and emotions from BM stimuli was correlated with global processing bias. Older adults performed more poorly on BM decoding and had a local processing bias. However, age differences in global-local processing could not fully explain differences in decoding actions or emotions from point-light displays. CONCLUSION: Therefore, although there was an association between age, perceptual processing bias, and detection of BM, other factors must be important in explaining age-related change in social perception.