TY - JOUR
T1 - Delay discounting and frontostriatal fiber tracts
T2 - A combined DTI and MTR study on impulsive choices in healthy young adults
AU - Peper, Jiska S.
AU - Mandl, René C.W.
AU - Braams, Barbara R.
AU - De Water, Erik
AU - Heijboer, Annemieke C.
AU - Koolschijn, P. Cédric M.P.
AU - Crone, Eveline A.
PY - 2013/7/1
Y1 - 2013/7/1
N2 - Delay discounting, a measure of impulsive choice, has been associated with decreased control of the prefrontal cortex over striatum responses. The anatomical connectivity between both brain regions in delaying gratification remains unknown. Here, we investigate whether the quality of frontostriatal (FS) white matter tracts can predict individual differences in delay-discounting behavior. We use tract-based diffusion tensor imaging and magnetization transfer imaging to measure the microstructural properties of FS fiber tracts in 40 healthy young adults (from 18 to 25 years). We additionally explored whether internal sex hormone levels affect the integrity of FS tracts, based on the hypothesis that sex hormones modulate axonal density within prefrontal dopaminergic circuits. We calculated fractional anisotropy (FA), mean diffusivity (MD), longitudinal diffusivity, radial diffusivity (RD), and magnetization transfer ratio (MTR), a putative measure of myelination, for the FS tract. Results showed that lower integrity within the FS tract (higher MD and RD and lower FA), predicts faster discounting in both sexes. MTR was unrelated to delay-discounting performance. In addition, testosterone levels in males were associated with a lower integrity (higher RD) within the FS tract. Our study provides support for the hypothesis that enhanced structural integrity of white matter fiber bundles between prefrontal and striatal brain areas is associated with better impulse control.
AB - Delay discounting, a measure of impulsive choice, has been associated with decreased control of the prefrontal cortex over striatum responses. The anatomical connectivity between both brain regions in delaying gratification remains unknown. Here, we investigate whether the quality of frontostriatal (FS) white matter tracts can predict individual differences in delay-discounting behavior. We use tract-based diffusion tensor imaging and magnetization transfer imaging to measure the microstructural properties of FS fiber tracts in 40 healthy young adults (from 18 to 25 years). We additionally explored whether internal sex hormone levels affect the integrity of FS tracts, based on the hypothesis that sex hormones modulate axonal density within prefrontal dopaminergic circuits. We calculated fractional anisotropy (FA), mean diffusivity (MD), longitudinal diffusivity, radial diffusivity (RD), and magnetization transfer ratio (MTR), a putative measure of myelination, for the FS tract. Results showed that lower integrity within the FS tract (higher MD and RD and lower FA), predicts faster discounting in both sexes. MTR was unrelated to delay-discounting performance. In addition, testosterone levels in males were associated with a lower integrity (higher RD) within the FS tract. Our study provides support for the hypothesis that enhanced structural integrity of white matter fiber bundles between prefrontal and striatal brain areas is associated with better impulse control.
KW - DTI
KW - delay discounting
KW - frontostriatal tracts
KW - impulsivity
KW - testosterone
UR - http://www.scopus.com/inward/record.url?scp=84878868969&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84878868969&partnerID=8YFLogxK
U2 - https://doi.org/10.1093/cercor/bhs163
DO - https://doi.org/10.1093/cercor/bhs163
M3 - Article
C2 - 22693341
SN - 1047-3211
VL - 23
SP - 1695
EP - 1702
JO - Cerebral cortex
JF - Cerebral cortex
IS - 7
ER -