Dimensional information-theoretic measurement of facial emotion expressions in schizophrenia.
Altered facial expressions of emotions are characteristic impairments in schizophrenia. Ratings of affect have traditionally been limited to clinical rating scales and facial muscle movement analysis, which require extensive training and have limitations based on methodology and ecological validity. To improve reliable assessment of dynamic facial expression changes, we have developed automated measurements of facial emotion expressions based on information-theoretic measures of expressivity of ambiguity and distinctiveness of facial expressions. These measures were examined in matched groups of persons with schizophrenia (n = 28) and healthy controls (n = 26) who underwent video acquisition to assess expressivity of basic emotions (happiness, sadness, anger, fear, and disgust) in evoked conditions. Persons with schizophrenia scored higher on ambiguity, the measure of conditional entropy within the expression of a single emotion, and they scored lower on distinctiveness, the measure of mutual information across expressions of different emotions. The automated measures compared favorably with observer-based ratings. This method can be applied for delineating dynamic emotional expressivity in healthy and clinical populations.
Department of Computer Science and Engineering, The Ohio State University, Columbus, OH 43210, USA.
Jihun
0000-0002-0680-0901
J
Hamm
Southern Methodist University, Dallas, TX 75205, USA.
Amy
0000-0003-2803-4520
A
Pinkham
Department of Psychiatry, Neuropsychiatry Section, University of Pennsylvania, Philadelphia, PA 19104, USA ; Philadelphia Veterans Administration Medical Center, Philadelphia, PA 19104, USA.
Ruben C
RC
Gur
Department of Radiology, Section of Biomedical Image Analysis, University of Pennsylvania, Philadelphia, PA 19104, USA.
Ragini
R
Verma
Department of Psychiatry, Neuropsychiatry Section, University of Pennsylvania, Philadelphia, PA 19104, USA.
Christian G
CG
Kohler