Biomedical subjects

W S Goldman

Publications and source records attributed to W S Goldman.

4 recordsLinked to original sources

PubMed1986

Motion-induced sickness following bilateral ablation of area postrema in squirrel monkeys.

Using squirrel monkeys as experimental subjects, we reexamined the disputed role of the area postrema (AP) in motion-induced vomiting. After anesthetization, the obex and rhomboid fossa were exposed surgically, and the AP was ablated by thermal coagulation using either a battery cautery or a CO2 microsurgical laser. Sham operations were performed on another sample of monkeys. Two or more weeks after surgery, all animals were given 10 daily 2-hour horizontal rotations at 30 rpm. Every monkey in both the lesions and sham samples vomited on two or more test days. While the vomiting characteristics were modified following ablation of AP, its function is not indispensible for the development of motion sickness in horizontally-rotated squirrel monkeys.

Animals↗

PubMed1985

Effects of head and body restraint on experimental motion-induced sickness in squirrel monkeys.

Each of 16 Bolivian-phenotype squirrel monkeys of mixed sex had a machine bolt mounted on the skull with acrylic cement; 13 were provided with temporary plaster body casts allowing free movement. With eyes open, all were rotated in the horizontal plane at 30 rpm every other day until vomiting occurred or for a maximum duration of 120 min/spin. Latencies for motion-sickness signs were recorded under three experimental conditions: free movement, torso fixed to an aluminum frame and both torso and head restrained by bolting to the frame. Subsequently, 10 monkeys from this sample were rotated while blindfolded with head and torso immobilized. Results partially confirmed human and animal findings reported by others: reduced mobility was accompanied by a reduction in the incidence and an increase in the latency of motion sickness. The importance of optokinetic input for the generation of motion sickness in this species was clear.

Animals↗

PubMedDate not supplied

Experimental motion sickness induced in squirrel monkeys by continuous off-axis horizontal rotation.

Under a variety of experimental conditions, nonrestrained adult male squirrel monkeys were subjected to continuous rotation in the horizontal plane at 33 rpm. Severity of motion-induced sickness was quantified by measuring latencies of three responses associated with sickness. Per- and postrotational nystagmus was recorded from a subsample of monkeys with permanent recording electrodes implanted in the bony orbits. Incidence of sickness depended on the time limits of stimulation imposed, and it occurred in a maximum of about 90 per cent of test sessions if rotation was continued for two hours. When subjected to ten once-per-day rotation sessions, only a few monkeys showed evidence of developing transient habituation of onset of motion sickness. Mean frequency of emetic episodes, however, declined over the latter half of the rotation series. Restricting visual cues by blindfolding the monkeys prevented most subjects from vomiting.

Animals↗

PubMedDate not supplied

Behavioral conditioning and experimental motion-induced sickness.

Adult male squirrel monkeys were the subjects of experiments conducted to determine whether or not repeated exposures to sickness-inducing horizontal rotation would result in behavioral conditioning of emetic responses. The development of conditioned food aversion and feeding suppression as a consequence of pre- and postrotation eating was quantified. It was concluded that neither instrumental conditioning nor classical conditioning were valid alternative hypotheses for the occurrence of repeated vomiting episodes over a period of ten daily exposures to motion. Conditioned aversion to fresh banana and feeding suppression developed gradually if rotation, which induced multiple bouts of vomiting, was sustained for 1- or 2-hour sessions. If spinning was terminated immediately after the first emetic response, no aversion or suppression emerged. The occurrence of food aversion, by itself, is questioned as a valid index of the presence of subjective concomitants of motion sickness in animals.

Animals↗