Disorders of emotional processing in amyotrophic lateral sclerosis

PURPOSE OF REVIEW: Amyotrophic lateral sclerosis (ALS) is a degenerative brain disease characterized by motor, behavioural and cognitive deficits. Only recently, emotional processing disorders have been shown in this disease. The interest in affective processing in ALS is growing given that basic emotion impairments could impact copying strategies and mood.

RECENT FINDINGS: Studies explore both basic emotion recognition and social cognition. Results are congruent on arousal and valence detection impairments, independently from the stimulus modality (verbal or visual). Further, recognition of facial expressions of anger, sadness and disgust is impaired in ALS, even when cognition is preserved. Clinical features such as type of onset and severity of the disease could be the cause of the heterogeneity in emotional deficits profiles between patients. Finally, a study employing diffusion tensor imaging showed that emotional dysfunctions in ALS are related to right hemispheric connective bundles impairments, involving the inferior longitudinal fasciculus and the inferior frontal occipital fasciculus.

SUMMARY: Research on emotional processing in ALS is still in its infancy and results are mixed. Future research including more detailed clinical profiles of patients and measures of brain connectivity will provide useful information to understand heterogeneity of results in ALS.