Worm Breeder's Gazette 8(1): 53

These abstracts should not be cited in bibliographies. Material contained herein should be treated as personal communication and should be cited as such only with the consent of the author.

Videocamera-Microcomputer System for Studying Nematode Behaviour

D.B. Dusenbery

A project is underway to evaluate the potential of using a video 
camera interfaced to a microcomputer for studying the behavior of 
small animals such as the nematode Caenorhabditis 
m has been assembled consisting of an 
inexpensive CCTV camera, a commercial computer using a 6809 
microprocessor, and a specially built interface for the SS-50 bus.  
The interface stores one bit of intensity information for each point 
in a 256 x 240 array.  The full frame can be stored in 7680 bytes of 
memory during a single scan of the camera.  Darkfield illumination of 
the animals is used to provide high contrast.  Software has been 
written to track individual nematodes and record changes in their 
direction of movement.  Twenty-five worms can be tracked 
simultaneously with a one second interval between sequential 
determinations of the position of each animal.  Chemical stimuli are 
carried in a flow of gas over the nematodes.  Initial experiments have 
used CO2 or O2 as stimuli.  Changes in both the rate of movement and 
the frequency of change of direction are readily observed.  Indeed the 
response to oxygen, a relatively weak stimulus by other methods, can 
be detected in one two minute stimulus cycle.  This observation 
suggests that this technique may be a major improvement in assaying 
for chemical stimuli, at least for volatile chemicals.