Modeling unipolar depression as a chaotic process.
This study inspected the deterministic structure of unipolar depression. Two women self-monitored sadness hourly 10 times a day for 6 months. One woman had a recurrent history of unipolar depression, and the other did not. Data were analyzed by visual inspection, examination of the Fourier transforms of the time plots, and the correlation dimension. Results suggested that in addition to a strong periodic component that existed only within the depressed subject's mood time series, a low-dimensional chaotic process might have been operating. In the nondepressed control subject, no such periodicity or process could be identified. The findings support maladaptive deterministic theories of mood disorders and have implications for the assessment of unipolar depression.
Department of Psychology, University of Hawaii at Manoa, Gartley Hall, 2430 Campus Road, Honolulu, Hawaii 96822. heiby@hawaii.edu
Elaine M
EM
Heiby
Ian S
IS
Pagano
Daniel D
DD
Blaine
Karl
K
Nelson
Rachel A
RA
Heath
D000328:Adult; D000339:Affect / Q000502:physiology; D003866:Depressive Disorder / Q000175:diagnosis* / Q000523:psychology*; D005260:Female; D005583:Fourier Analysis; D006801:Humans; D008960:Models, Psychological; D017711:Nonlinear Dynamics; D010507:Periodicity; D011569:Psychiatric Status Rating Scales; D012044:Regression Analysis; D012647:Self-Assessment; D013997:Time Factors