Human performance with a seventeen-arm radial maze analog.

Results using radial mazes suggest rats may have a greater short-term memory (STM) capacity than the human "magical number seven." We examined spatial STM in humans using a radial maze analog drawn on paper. Subjects were instructed to lift, in "random" order, each of 17 cardboard flaps arranged radially around a center point. Fifteen undergraduate subjects, tested seven trials a day on 2 consecutive days, averaged 15.4 correct choices per trial. Thus, humans perform equally well on a 17-arm radial maze analog as rats do on a 17-arm radial maze, suggesting comparable spatial STM capacities, and perhaps homologous brain substrates for these tasks, in these two species.