Observers judged whether 2 successive computer-displayed rotations of a cube were the same or different. With respect to the observers, each rotation was about a vertical axis (Y), a horizontal (line-of-sight) axis (Z), an axis tilted just 10 degrees from vertical or horizontal, or a maximally oblique axis. Independently, with respect to the cube, each rotation was about a symmetry axis through...

Electrophysiological studies of symmetry have found a difference wave termed the Sustained Posterior Negativity (SPN) related to the presence of symmetry. Yet the extent to which the SPN is modulated by luminance-polarity and colour content is unknown. Here we examine how luminance-polarity distribution across the symmetry axis, grouping by luminance polarity, and the number of colours in the s...

Symmetry is a biologically relevant, mathematically involving, and aesthetically compelling visual phenomenon. Mirror symmetry detection is considered particularly rapid and efficient, based on experiments with random noise. Symmetry detection in natural settings, however, is often accomplished against structured backgrounds. To measure salience of symmetry in diverse contexts, we assembled mir...

In this paper, we propose a symmetry axis detection network that can correct asymmetric parts by itself. Our network compares directional blurring of omnidirectional image edges, which plays a significant role in asymmetry detection and correction. The output layer consists of oscillatory neurons, which activates symmetry axes one by one. Given activated symmetry axis, network estimates the dif...

It is a well known fact that a symmetric spacecraft with two control torques supplied by gas jet actuators is not controllable, if the two control torques are along axes that span the two-dimensional plane orthogonal to the axis of symmetry. However, feedback control laws can be derived for a restricted problem corresponding to attitude stabilization about the symmetry axis. In this connguratio...

It is a well known fact that a symmetric spacecraft with two control torques supplied by gas jet actuators is not controllable if the two control torques are along axes that span the two dimensional plane orthogonal to the axis of symmetry However feedback control laws can be derived for a restricted problem corresponding to attitude stabilization about the symmetry axis In this con guration th...

Four experiments investigated the roles of layout geometry in the selection of intrinsic frames of reference in spatial memory. Participants learned the locations of objects in a room from 2 or 3 viewing perspectives. One view corresponded to the axis of bilateral symmetry of the layout, and the other view(s) was (were) nonorthogonal to the axis of bilateral symmetry. Judgments of relative dire...

Can subjects voluntarily set an internal coordinate frame in such a way as to facilitate the detection of symmetry about an arbitrary axis? If so, is this internal coordinate frame the same as that involved in determining perceived top and bottom in object recognition and shape perception? Subjects were required to determine whether dot patterns were symmetric. Cuing the subjects in advance abo...