[Human visual evoked potentials to bars and cross-like figures]

Temporal and amplitude characteristics of averaged visual evoked potentials to presentation of lines, corners and crosses with different orientation recorded in 19 adult healthy subjects were compared in 34 derivations. In all subjects, the latencies of P1, N2, and P3 were shorter while their amplitudes were higher for crosses than for lines. The effect of lengthening of P1 peak latency from occipital to temporal cortex was mostly pronounced for EPs to a bar, whereas as increase in the P1 amplitude was most evident for a cross-like figure. Correlation of these data with: i) greater magnitude and shorter latencies of responses to crosses vs. bars in a half of cat striate neurons, ii) sensitivity of cells in monkey inferior temporal cortex to star-like figures, and iii) relatively better human recognition of figures with comers than with lines, as well as significance of the effects obtained for detection of image features in different areas of the human visual cortex is discussed.