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The dificulty of testing the skill of visual recognition, in the absence of faceto-face contact between examiner and candidate, has stimulated the development of visual material for inclusion in multiple choice question (MCP) papers set in postgraduate examinations conducted three times a year in multiple centres. Having considered various modes for the presentation of such visual material, the use of multiple prints was chosen. This paper describes the techniques that have been used for the production of multiple prints of radiographs, CT scans, sugace anatomy photographs, and hiswlogical and histopathological material. Guidelines for the production of high quality p'nts, with indicators, and with suficient clarity and definition to maximise fairness to the candidates answering the questions, are given. Particular emphasis is paid to the need for the content expert to work in close liaison with the photographer in the production of such material.Med Teach Downloaded from informahealthcare.com by UB Heidelberg on 11/16/14For personal use only.

A passive operant-avoidance procedure was employed to condition 12 bullfrogs and 6 grass frogs to inhibit the righting-reflex. To avoid an electric shock of .8 mA, both species, when flipped, remained frozen rather than showing the short-latency righting-reflex; 6 toads failed to show passive-avoidance learning. The data are considered within the context of species-specific behavior and tonic immobility.

Three common bullfrogs of the Rana catesbiana strain were conditioned, employing an operant-avoidance procedure, to inhibit the high-priority, biologically adaptive righting reflex. To avoid an electric shock of _6, .8, or 1.0 rnA, bullfrogs, when flipped, remained passively on their backs rather than exhibiting the normal short-latency righting response. The data are discussed in the context of the species-specific aspects of avoidance behavior.Considerable data on geotropic behavior in the common bullfrog (Rana catesbiana) suggest that position and attitude adjustments are both precise and adaptive in that they facilitate the bullfrog's survival in its natural habitat. Such behaviors were first described systematically by Dickerson (1906), who asserted that a frog is "not at ease" unless its head is uppermost. That a bullfrog can right itself with its forebrain not intact is evidence that the "righting-retlex" is. indeed, a reflex.Researching with leopard frogs, McGill (1960) has shown that these frogs find it adaptive in escape or avoidance paradigms not to make the shuttle response but, rather, to spread out their bodies, remain passive. and take the shock. Although spreading seemed to reduce the discomfort of shock, it was maladaptive in that it led to the death of the frogs. Boice (1968) demonstrated that escape and avoidance responses are incompatible with behavioral passivity. In both researches. the shock level was extreme.The present research attempts to answer two important questions:(a) can a high-priority biologically adaptive response. specifically the righting reflex in the common bullfrog, be brought under stimulus control and inhibited; and (b) can the bullfrog learn an operant-avoidance response? METHOD SubjectsThe subjects were four adult male frogs of the Rana catesbiana (common bullfrog) variety captured in the wild. The frogs were housed in a metal tub which was half filled with water; laboratory temperature was maintained at 20 o e. The frogs were fed live grasshoppers and crickets for the fust 3 weeks; and as live food became unavailable, they were force-fed meal worms for thenext weeks of experimentation.Requests for reprints should be sent to C. Brian Harvey. Department of Psychology. University of Missouri-Rolla. Rolla. Missouri 65401. Dr. C. T. Morgan sponsors this paper and takes full editorial responsibility for its content. ApparatusShock was delivered by a Grason-Stadler No_ 700 shock generator and a Hewlett-Packard supply set at 28 V. Probes were attached to the frogs via a wire harness wrapped around the pelvic girdle below the erostyle.