Theta oscillations during the processing of monetary loss and gain: a perspective on gender and impulsivity.
Event-related oscillations (EROs) have proved to be very useful in the understanding of a variety of neurocognitive processes including reward/outcome processing. In the present study, theta power (4.0-7.0 Hz) following outcome stimuli in the time window of the N2-P3 complex (200-500 ms) was analyzed in healthy normals (20 males and 20 females) while performing a gambling task that involved monetary loss and gain. The main aim was to analyze outcome processing in terms of event-related theta power in the context of valence, amount, gender, and impulsivity. The S-transform was used for the signal processing of the ERO data in terms of time-frequency-power. Results from filtered waveforms showed a partially consistent phase-alignment of the increased theta activity corresponding to N2 and P3 components following the outcome stimuli. Gain conditions produced more theta power than loss conditions. While there was anterior involvement in both gain and loss, posterior activation was stronger during gain conditions than during loss conditions. Females exhibited posterior maxima during gain conditions while males had an anterior maxima during both loss and gain conditions. The current source density of theta activity in females involved larger areas with a bilateral frontal activity while males predominantly had a frontal midline activity. Theta power was significantly higher in females than males across all conditions. Low theta (4.0-5.5 Hz) predominantly contributed to the posterior activity during gain conditions. High theta (5.5-7.0 Hz) was more associated with impulsivity measures than low theta activity. These findings may offer valuable clues to understand outcome processing, impulsivity, and gender differences.
Kamarajan
Chella
C
Henri Begleiter Neurodynamics Laboratory, Department of Psychiatry, Box 1203, SUNY Downstate Medical Center, 450 Clarkson Avenue Brooklyn, NY 11203, USA. kam@cns.hscbklyn.edu
Rangaswamy
Madhavi
M
Chorlian
David B
DB
Manz
Niklas
N
Tang
Yongqiang
Y
Pandey
Ashwini K
AK
Roopesh
Bangalore N
BN
Stimus
Arthur T
AT
Porjesz
Bernice
B
D000293:Adolescent; D000328:Adult; D001683:Biological Clocks / Q000502:physiology*; D001921:Brain / Q000033:anatomy & histology / Q000502:physiology*; D001931:Brain Mapping / Q000379:methods; D004569:Electroencephalography / Q000379:methods; D005071:Evoked Potentials / Q000502:physiology; D005260:Female; D005625:Frontal Lobe / Q000033:anatomy & histology / Q000502:physiology; D005715:Gambling / Q000523:psychology; D006801:Humans; D007175:Impulsive Behavior / Q000503:physiopathology*; D008297:Male; D008606:Mental Processes / Q000502:physiology*; D009483:Neuropsychological Tests; D012201:Reward; D012727:Sex Characteristics; D012815:Signal Processing, Computer-Assisted; D013826:Theta Rhythm; D055815:Young Adult