Lei Yang, Abstract Co-Author: Nothing to Disclose

Jie Tian PhD, Presenter: Nothing to Disclose

Xiaoxiang Wang, Abstract Co-Author: Nothing to Disclose

To identify gender differences in brain activation during the visual stimuli generated by the pictures from IAPS (International Affective Picture System).

Eight male (mean age 24.36years, SD 3.56) and eight female (mean age 24.55 years, SD 4.32), all right-handed, were selected in this study. The usual exclusion criteria for MRI were applied. SAM ratings and skin conduct response were used to confirm that these pictures elicit the correct emotional experience. The stimuli were presented in an event-related design for 500ms and were arranged in a fixed randomized order which counterbalanced across subjects. The interval between each stimulus was randomly varied between 7.5s-10.5s to ensure that event onsets were evenly distributed in time across image slices. A fixation cross was presented during the intertribal interval. Images were acquired with a 3.0 T Magnetom whole-body MRI scanner (Siemens, Germany). 24 slices T2* weighted images were obtained every 3s (TR) using EPI sequence (TE=30ms, Fov=192mm, flip angle = 900, matrix 64*64, thickness = 5mm, no gap).The anatomical MRI was acquired using a T1-weighted, three-dimensional gradient-echo pulse-sequence. The fMRI data were analyzed using statistical parametric mapping with SPM2b.

Repeated-measures analysis ANOVA with task (positive, negative, neutral), gender (male, female) to compare the extent and magnitude upon activation in different brain regions. Although no significant gender difference in valence and arousal was obtained, male displayed stronger brain activity to positive stimuli in the inferior and medial frontal gyrus, whilst female displayed stronger brain activity to negative visual stimuli in the anterior and medial cingulated gyrus. Amygdala activation was found in the pleasant condition for male only. In female, significantly increased activity was found in the medial prefrontal and thalamic regions by both positive and negative stimuli.

The result confirms that different activation exists in variable brain regions for genders during emotion processing. The result also indicates that gender differences may response more to negative stimuli than positive.

Yang, L, Tian, J, Wang, X, Gender Differences in the Processing of Standard Emotional Visual Stimuli: An Event-related fMRI Study.  Radiological Society of North America 2004 Scientific Assembly and Annual Meeting, November 28 - December 3, 2004 ,Chicago IL. http://archive.rsna.org/2004/4410209.html