Hemispheric asymmetry in the processing of high and low spatial frequencies: a facial recognition task

The research investigated the relationship between spatial frequency and visual field in a facial recognition task. Faces of neutral affect (Ekman, 1979) were tachistoscopically presented to the right or left visual field. The faces were presented alone, or masked with square wave gratings of 1, 24, or 48 cycles/degree, for a duration of 10 msec. Accuracy in recognizing each target face from a group of five served as the dependent measure. Subjects were 15 males and 15 females. ANOVA results included a frequency x visual field interaction effect (p less than .001). As was hypothesized, LVF errors were highest in the absence of low spatial frequencies, while RVF errors were highest when a higher range of spatial frequencies was removed. These results confirm that the hemispheres show a differential efficiency in processing high and low spatial frequency information in faces. They also offer empirical evidence to support the clinical findings that both hemispheres contribute to facial recognition.