Higher-Order Conditioning and Sensory Preconditioning of a Taste Aversion with an Exteroceptive CS1

An exteroceptive stimulus compound (context) was employed as CS1 in higherorder conditioning (H-OC, Experiments I and II), and sensory preconditioning (SPC, Experiment III) of a saccharin (CS2) aversion in rats. The results indicated that aversions were established with the H-OC as well as with the SPC procedures. Stimulus generalization and first-order conditioning explanations were ruled out by appropriate controls. A CS1-extinction period, performed prior to testing, did not affect the H-OC aversion, whereas it reduced the SPC aversion at least partially. These findings imply that interoceptive (taste, nausea) and exteroceptive stimuli (context) are readily associable in rats. Implications of the resemblance between the SPC procedure and long-delay taste-aversion learning are discussed.

Maintained Generalization Gradients with Contingent and Non-Contingent Reinforcement

Contingent or non-contingent schedules of reinforcement were used in a maintained-generalization testing procedure. Four adult male white Carneaux pigeons with previous experience in generalization-testing procedures served as subjects. Subjects pecked a key for food reinforcement in the presence of various line-tilt orientations. A discrete-trial procedure with stimulus durations of eight sec. and a mean intertrial interval of 45 sec. was used. No difference in the shape of the obtained gradient as regards the presence or absence of a response contingency was observed, Results are discussed in relation to work on interoceptive vs exteroceptive stimulus control of behavior.

Development of a Stimulus-Variation Seeking Scale for Adults

The development of a Stimulus Variation Seeking Scale (SVSS) which purportedly measures the amount of exteroceptive stimulus variation seeking customarily sought by an individual is described. The SVSS had high test-retest reliability and some discriminant validity in that it showed little or no relationship to manifest anxiety, authoritarianism, or scholastic aptitude. However, the scale correlated positively with perceived movement in the autokinetic situation, sensation seeking as measured by the Sensation Seeking Scale and originality as measured by a modified version of Guilford's Unusual Uses Test, indicating that the scale possesses some convergent validity.