1. Motor versus Psychomotor? Deciphering the Neural Source of Psychomotor Retardation in Depression
- Author
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Xue Mei Song, Dong‐Yu Liu, Dusan Hirjak, Xi‐Wen Hu, Jin‐Fang Han, Anna Wang Roe, De‐Zhong Yao, Zhong‐Lin Tan, and Georg Northoff
- Subjects
major depressive disorder ,middle temporal visual complex ,motion perception ,primary motor cortex ,psychomotor retardation ,Science - Abstract
Abstract Major depressive disorder (MDD) is characterized by psychomotor retardation whose underlying neural source remains unclear. Psychomotor retardation may either be related to a motor source like the motor cortex or, alternatively, to a psychomotor source with neural changes outside motor regions, like input regions such as visual cortex. These two alternative hypotheses in main (n = 41) and replication (n = 18) MDD samples using 7 Tesla MRI are investigated. Analyzing both global and local connectivity in primary motor cortex (BA4), motor network and middle temporal visual cortex complex (MT+), the main findings in MDD are: 1) Reduced local and global synchronization and increased local‐to‐global output in motor regions, which do not correlate with psychomotor retardation, though. 2) Reduced local‐to‐local BA4 – MT+ functional connectivity (FC) which correlates with psychomotor retardation. 3) Reduced global synchronization and increased local‐to‐global output in MT+ which relate to psychomotor retardation. 4) Reduced variability in the psychophysical measures of MT+ based motion perception which relates to psychomotor retardation. Together, it is shown that visual cortex MT+ and its relation to motor cortex play a key role in mediating psychomotor retardation. This supports psychomotor over motor hypothesis about the neural source of psychomotor retardation in MDD.
- Published
- 2024
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