The Ability to Visually Recognize Facial Emotions during the Initial Stages of Alzheimer’s

Abstract

Background: Alzheimer’s sufferers (AS) are unable to visually recognize facial emotions (VRFE). However, we do not know the kind of emotions involved, the timeline for the onset of this loss of ability to recognize facial emotional expressions during the natural course of this disease and the existence of any correlation with other comorbid cognitive disorders. For that reason, the authors aimed to determine whether a deficit in facial emotion recognition is present at the onset of Alzheimer disease, distinctly and concurrently with the onset of cognitive impairment or is it a prodromal syndrome of Alzheimer’s Disease before the onset of cognitive decline and what emotions are involved. A secondary aim was to investigate relationships between facial emotion recognition and cognitive performance on various parameters. Method: Single Blind Case-control study. Setting in Memory clinic. Participants: 12 patients, (AS) and 12 control subjects (CS) were enrolled. Measurements: Quantitative information about the ability for facial emotion recognition was obtained from Method of Analysis and Research on the Integration of Emotions (MARIE). The Mini Mental Status Examination (MMSE), the Picture Naming, the Mattis Dementia Rating Scale (DRS), and the Grober & Buschke Free and Cued Selective Reminding Test (FCSRT) tests were used to measure cognitive impairment. Results: We note that the AS have a problem with the visual recognition of facial emotions with existence of a higher threshold for visual recognition. The AS is less sensitive to the visual recognition cues of facial emotions. AS is unable to distinguish anger from fear. It would be a possible explanation for some acts of aggressiveness seen in the clinical and home setting demonstrated by “AS with behavioral disturbance”. The anger-fear series was found to be the first affected in the course of Alzheimer’s. The appearance of the curve is sigmoid for the control group and linear for the Alzheimer’s patients with a cognitive distortion when the VRFE is represented graphically with percentage of correct recognition plotted on the “y” axis and the selected images presented as stimulus with measures of density of emotion plotted on the “x” axis. In both groups, it is intuitively and theoretically expected that correct recognition will be directly proportional to the density of represented emotion in the stimulus image. This hypothesis is true for CS but not so for AS. The MARIE (see below) processing of emotions seems to be strengthened by the optimal cognitive functions showing the hypothesis applies to CS but not uniformly in AS. This anomaly in the AS is evidenced by the decline of the cognitive functions contributing to abovementioned “linearization” in the graphic representation. There is a direct positive correlation between the results of MARIE and the performance on cognitive tests. Conclusion: The administration of a combination of DRS, FCSRT, and MARIE to patients screened for possibly emerging Alzheimer’s could provide a more detailed and specific approach to make a definitive early diagnosis of Alzheimer’s. The Alzheimer’s patients found it difficult to distinguish between anger and fear.