Search slope and movement speed.

<p><b>A. Search time as a linear function of number of objects searched</b>. Data of a typical observer, O7, in the free search task. Each grey dot is for one trial. The black line is the fitting line, whose slope corresponds to the time to identify one object, . <b>B. Average trajectories for different target positions</b>. Data of the same observer O7 in the training of reach. Red filled circle denotes the starting position. Grey filled circles denote positions of objects. In each trail, the observer moved the finger from the starting position to one designated position. Black lines denote trajectories of hand movement averaged across trials. The number above an object denotes the measured movement speed towards the object (<i>cm/s</i>). Note that the movement speeds differ little in different movement directions. The mean speed across all target positions is regarded as the observer's movement speed, .