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ANIMAL BEHAVIOUR, XIII, 4

SOME APPLICATIONS OF CLOSED CIRCUIT TELEVISION TO THE STUDY OF ANIMAL BEHAVIOUR,By BETTY DAWSON, B. M. FOSS & C. C. KIERNAN, Birkbeck College, Institute of Education and Birkbeck College,

University ofLondon.

Relatively inexpensive closed circuit tele-vision (CCTV) units are now available . It wassuggested that the use of such units increasesexperimental control in general, and also re-duces the possibility of experimenter-subjectinteraction effects (Rosenthal, 1963) . Secondly,it was argued that the use of CCTV facilitatesthe recording of the general behaviour of theorganism, and therefore allows data which maybe of importance in the evaluation of experi-mental results to be gathered . Three experi-ments were discussed in which use was made ofCCTV. (1) An experiment on observationallearning in budgerigars (B.D.), in which tame-ness was used as a variable, and in which a fullrecord of the occurrence and form of goal-directed behaviour was required. (2) An experi-ment on the acquisition of learning sets byIndian Hill Myanhs (B.D.), in which again a fullbehavioural record was required. In both experi-ments there was danger of distortion of resultsby experimenter-subject interaction ; in the firston the basis of differential effects of the presenceof the experimenter on tamed and untamed birds,and in the second on the basis of the subjectsutilizing cues unintentionally provided by theexperimenter (the Clever Hans phenomenon) .In both cases the use of CCTV eliminated theseproblems, and also allowed a full record of thegeneral behaviour of the organism to be kept .The results of the first experiment showed that`tameness' affected speed of acquisition of goal-directed behaviour, but did not affect imitationof the methods used to reach the goal, whichwere copied by `observers' in both groups . (3)Comparative data on the general behaviour ofhooded rats under conditions of direct obser-vation and camera observation, over six 5-

minute trials, was presented (C.C.K.) . It wasshown that the groups differed significantly overtrials on measures of sniffing, grooming, freez-ing and rearing (p<0 .01 in each case), but noton amount of walking . Secondly, it was shownthat the direct observation group was sig-nificantly more variable within days than thecamera observation group, on the rearing,grooming and freezing measures (p<0 .05 ineach case). It was concluded that method ofobservation modified behaviour, and that of thetwo methods the camera observation techniquewas superior, greater experimental control beingillustrated by reduced within-groups variances.Further aspects of this experiment were de-scribed in order to illustrate the value of therecording technique (Bindra & Blond, 1958) .The camera observation group was split, 6animals being given a subcutaneous injection ofdl amphetamine sulphate, and 6 saline . Theresults of a 10-minute observation period showedthat drugged animals spent more time walkingand sniffing, and less time grooming and freezingthan did saline treated animals (p<0 .01 ineach case). Finally, the effects of stimulation(70 db white noise, 0.5 seconds, every 5 seconds)on general behaviour were illustrated, and anattempt to integrate the results of maze studies(Steinberg, Rushton & Tinson, 1961) and Skin-ner box studies (Kiernan, 1965) on the responseto novelty under amphetamine sulphate wasmade in consideration of these results .'Thornvision' cameras, and 16 mm . 1 inch

or wide angle lenses with a sensitivity to sceneillumination of 5 ft. lamberts, a resolution greaterthan 450 lines, and depth of focus dependent onF value, were used in all experiments reported .