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Observations were made of the personal space behaviors of same-sex pairs of children, aged 6–16. Results indicated that children used more space as they grew older and that adult proxemic behaviors were acquired by age 12. While in the younger children no sex differences were present for the proxemic behaviors of distance and body orientation, males were found by early adolescence to stand farther apart and at greater angles than females. The development of personal space and of sex differences in these behaviors is discussed in the context of social learning.

Human performance during a low-frequency vibratory environment was investigated. The performance measures of interest were the accuracy and total time of a whole-body orientation task. A zero vibration condition as well as frequencies of 2, 5, and 8 Hz. were studied. Amplitude was held constant at 0.09 in., resulting in acceleration intensities from 0.04 to 0.58 g. Performance was studied before, during, and after exposure to the vibration environment. Twenty male subjects participated in the investigation in both sitting and standing body positions. Vibration exposure times were 20 min. for all sessions. The task used in this investigation was a body orientation task that required subjects to orient their bodies as quickly and as accurately as possible toward one of a series of colored lights located at angles of 15, 30, and 60° on either side of a zero reference plane. The results indicated that the shortest travel time was obtained under zero vibration conditions but that most accurate performance was obtained under vibrations of 2 Hz. Differences in performance were also found between the two body positions and direction of orientation.

(1971). Body Orientation: A Workable Technique for Self-Discovery. Journal of Health, Physical Education, Recreation: Vol. 42, No. 1, pp. 44-57.

The constancy of object orientation was investigated by tilting S backwards at angles of 0°, 25°, 50°, or 75° in the median plane in order to match a line target, previously presented with S upright. The orientation of the target was either 0° (vertical), 30° or 60° (top toward S). The task entailed the perception of target orientation relative to the direction of gravity, hence S's body tilt had to be taken into account. Ss showed nearly perfect constancy in all conditions, however line tilt was a significant factor. Errors in matching the target orientation did not vary with body tilt although errors in apparent body orientation yielded a negatively accelerated function of body tilt. Several paradigms representing orientation constancy were discussed.

1. With suitable arthropods, such as the diplopods, it can be shown that body orientation following passive unilateral tension involves the homostrophic reflex. The phenomenon is exhibited when the animal is quiescent and during forward locomotion, but nothing of the sort appears in backward locomotion. 2. Receptors for the homostrophic reflex are in the body wall and are distributed throughout the length of the animal. 3. The effector nerves take their origin from the ganglia of the head alone. 4. The diplopods are stereotropic, the head turning toward the side in contact with a solid surface only as long as some part of the body maintains contact. Under suitable conditions stereotropism may mask the homostrophic reflex. 5. When a diplopod is in contact with two lateral surfaces of equal extent the path upon emergence is a straight one, conforming to the law of the parallelogram of forces.

Sr~mmary.-Field independence, as measured by the magnitude of error in judging true vertical on the Rod and Frame test, has been considered to be related to the utilization of body cues by Witkin, er al. (1954). Benfari and Vitale (1965) have used one portion of the Rod and Frame test, analyzed in terms of direction of error from the vertical, to determine if Ss were "body-oriented." If field-independence and body-orientation measures tap the same attribute, then they should be highly correlated. Body orientation was not significantly related to field independence when data from 46 adult males were analyzed using both procedures. Witkin, Lewis, Hertzman, Machover, Meissner, and Wapner ( 1954) defined the concept of perceptual style in terms of a field-dependent-field-independent continuum. Field-independent Ss mere considered to be more sensitive to body cues than those classified as field dependent. Witkin, et al. (1954) used the mean error in degrees (without regard to direction of error) on the Rod and Frame Test (RFT) to differenciate individuals along the perceptual style continuiun.

Intraventricular injection into rats of antiserum to rat synaptic membrane fraction (Anti-SMF) produced recurrent epileptiform activity bilaterally in the caudate nuclei, as well as behavioral alterations, on two caudate-mediated tasks involving body orientation. No change was seen on a control task previously reported to be unaltered by caudate lesions. Rats either injected with antiserum to erythrocytes or uninjected had normal EEGs and behavioral responses. It is concluded that antibodies directed against the synaptosome membrane fraction are capable of producing behavioral alterations as well as relatively long-lasting epileptiform activity in rats.

The structure of the large vestibular apparatus of the harp seal (Pagophilus groenlandicus) is similar to that of other mammals. However, the posterior semicircular canal is the smallest of the three canals and the plane of the lateral is below that of the posterior semicircular canal. An additional sensory end organ (crista neglecta) is present about 0.75 mm from the posterior crista. The neuroepithelium of the crista neglecta is similar to that of the crista of the semicircular canals and consists of large supporting and sensory cells, the sensory hairs of which project into the cupula. No otoconia were seen on the crista neglecta as were present on the otolithic membrane of the maculae utriculi and sacculi. A large macula utriculi and crista neglecta may be necessary for body orientation during diving.

Perceptual differences were investigated at the first grade level among Negro and white lower class children and middle class white children; and nursery, kindergarten, and first grade middle class white children. Half of the nursery school children had been given special exercises to enhance bodily awareness. A rod-and-frame test, the Frostig test, and the Metropolitan Achievement test were the criterion measures. Lower class children were less effective; race was not a significant factor; special exercises were beneficial; and perceptual performance was more highly correlated with predicted academic success for girls.

THERE is, I think, a fallacy which is frequently made in many of the problems dealing with the body orientation of Crustacea. I believe that practically all biologists dealing with this subject have accepted the idea that the position of the centre of gravity is a matter of great importance. Thus, to quote just one of the many statements which have been made along these lines: S. R. Williams1 says, “A sinking animal, like a lifeless body, always falls with the heavy end downwards.” Lifeless bodies do not sink with the heavy end downwards unless their specific gravity is considerably greater than the liquid in which they are sinking. Not only can this be demonstrated by experiment but also it is in agreement with standard text-book hydrodynamics.

Between 2 sources of light, free-swimmingArtemia salina turn their ventral side towards the brighter one. The ratio of the 2 light intensities at the threshold for this reaction is independent of the direction of gravity. This shows, together with other observations, that the body orientation is exclusively controlled by the direction of the impinging light.

Data are presented on the drag and lift coefficients of prismatic bodies with an aspect ratio of λ=0.15–1.0 near a screen. The bodies were placed in the low velocity stream so that the planes of the square bases of the bodies were parallel to the screen plane. Body orientation in the scream corresponded to the minimum projected frontal area. The experiments were conducted in the Reynolds number range from 2·105 to 9·105 (the characteristic linear dimension is the side of the base). It is shown that approach of the prismatic models to the screen, simulating the ground, leads to some change of the drag coefficient and the appearance of a significant lift force tending to separate the model from the screen.

Previous experiments (Grant & Kaestner, 1955; Miles & Lewis, 1956; Provins, 1956) have shown no consistent differences attributable to handedness in performance on perceptual motor tasks. Grant and Kaestner (1955) found interaction between handedness and difficulty of task. The purpose of this experiment was to examine left- and right-handed performance on a complex motor task (Humphries & Shephard, 1955). On the basis of Humphries' model (1958) for predicting performance on the Toronto Complex Coordinator (TCC) for various control-display-subject relations, the predicted performance in each of three subject orientations was examined using left and right handed Ss. METHOD The task was 'out of phase' (CD-3) on the Toronto Complex Coordinator (Shephard, 1955). Ss practiced in Positions B-3, B-6, or B-9. The control stick projected toward S and was parallel to the floor. Ss were 15 left-handed and 15 right-handed randomly selected male university students. An S was considered left-handed if he did any two tasks (eating, writing, or throwing a ball) with his left hand (Miles & Lewis, 1956). The experimental design was a 2 X 3 factorial one (two preferred hands, three body orientations) with 6 independent cells, each one consisting of 5 independent observations. Each S was given standard instructions and demonstration and then performed for one period of 5 min. Ss were run randomly as to both position and handedness. Measures were total number of matches, error-match ratio, and error persistencetotal error ratio. These measures are described elsewhere (Shephard, 1955).

The egocentric upright was separated from the spatial vertical by rotating the O 90 deg to the right and left. The primary direction of autokinesis shifted in accord with the changes in body tilt. Therefore, it was concluded that the direction of apparent motion is egocentrically determined.

The decrease in apparent tilt of a physically tilted line has been ascribed by Gibson to a change in the visual modality ( 1 ) . Here such effects are ascribed to change in a reference system for pc thus, changes will occur in both perceived orientation of the tilted visual object and of the longitudinal body axis. Accordingly, the main experimental variable here was exposure of S in a dark room to a luminous line tilted 20" right. S was seated in a chair with head immobilized in the median plane. Two dependent variables were used: perceived visual object orienration, as measured by adjustment of a luminous line so that it appeared verrical; and perceived longitudinal body axis orientation, as measured by adjustment of a luminous line so that it appeared parallel to S's longitudinal body axis. Both tasks were performed before and after exposure to the tilted line. Three independent groups, 16 Ss in each, were used for 2-, 5-, and 10-min. exposure periods. Within each group, half the Ss were tested on body orientation first and the remainder were tested on object orienration first. Before exposure, a line and the body axis, both physically verrical, were perceived as verrical. During exposure Ss reported they saw the tilted line "straighten;" and eirher they "felt" their bodies tilted or "wanted to" tilt their bodies in the direction of the tilted line. Compared to before, following exposure to the line tilted right there were significanr changes. A physically vertical line was perceived as tilted left (mean adjusrmenr for line to be seen as verrical, pooled exposure groups, was 0.83" right of physical verrical) and the physically vertical body axis was perceived as tilted righr (mean adjustment for line to be seen parallel to longitudinal body axis, pooled exposure groups, was 1.98" right of physical body axis). The findings show that, while S is vertical, during exposure to a visual object tilted righr, there are changes toward alignment in perceived orientation of the visual object tilted right and the verrical body axis, viz., they appear rotated toward each other. The findings su-eest that the tendency toward movemenr, occurring during exposure to the tilted visual object, plays a role in the observed perceptual changes.