Asymmetrical activity over the frontal cortex has been implicated in the experience and expression of emotions and motivations. Explanations of the research have suggested that relatively greater left frontal activity is associated with positive affect and/or approach motivation, and that relatively greater right frontal activity is associated with negative affect and/or withdrawal motivation. ...

The mechanism of differentiation with asymmetrical and symmetrical reinforcement was analysed on the basis of different impairments after medial and lateral prefrontal lesions. The medial prefrontal lesions impaired the retention of asymmetrical differentiation whereas the symmetrical differentiation was slightly or not impaired at all. The lateral prefrontal lesions impaired moderately the asy...

Evidence is reported indicating that the perception of apparent motion is better predicted by the multiplicative combination of luminance changes at two element locations than by the sum or squared-sum of the luminance changes, or by the motion energy in the stimulus. Because the results were obtained with a stimulus for which motion was specified by simultaneous luminance changes, they support...