Authors:

Kipps, C.M., Duggins, A.J., McCusker, E.A. & CALDER, A.J.

Reference:

Year of publication:

2007

CBU number:

6433

Abstract:

Patients with Huntington's disease, can show disproportionate impairments in recognising facial signals of disgust, but the neural basis of this deficit remains unclear. Functional imaging studies have implicated the anterior insula in the ability to recognise disgust, but have identified other structures as well, including the basal ganglia. We used voxel-based morphometry (VBM) to map regional variations in grey matter volume in participants carrying the mutation for Huntington's disease, and correlated this with their performance on a test of facial emotion recognition for six basic emotions (disgust, fear, anger, happiness, sadness, surprise). The volume of the anteroventral insula was strongly correlated with performance on the disgust recognition task. The amygdala volume (bilaterally) correlated with the ability to recognise happy facial expressions. There was marked specificity of the regional correlations for the emotion involved. Recognition of other emotion expressions, or more general cognitive or motor performance as measured by a standardised rating scale (UHDRS), did not correlate with regional brain volume in this group. Control participants showed no effect for any measure. The strong linear correlations for disgust and happiness recognition imply direct involvement of the anterior insula in disgust appreciation in Huntington's disease, and a similar role for the amygdala in recognising happy facial expressions. The absence of a correlation with the basal ganglia suggests a less critical role for these structures in disgust recognition than has previously been suggested. The findings also highlight the role of neurodegenerative diseases combined with statistical imaging techniques in elucidating the brain basis of behaviour and cognition.