While the 4 th e o r ie s o f la te n t in h ib itio n d iscu ssed thus fa r are eq u ally unable to account for th e r e s u lts o f E xpts, 10a and 10b, the Wagner model appears to provide a b e tte r exp lan ation o f la te n t in h ib itio n in gen eral than do the r iv a l th e o r ie s. U nlike the Wagner model, which proposes th a t the decrement in p rocessin g a preexposed CS paired w ith a US, when preexposure and co n d ition in g t r i a l are separated by a com paratively long IS I, i s because the occurrence o f the CS on the con d ition in g t r i a l is predicted by other cues in the environment ( i . e . , retr iev a l-g e n e ra ted prim ing). Mackintosh proposes th a t a preexposed CS lo s e s sa lie n c e because the CS i t s e l f does not p red ict any event th at is not already p red icted by other cues in the environment. Thus the Wagner model, but not th a t o f M ackintosh, p red icts la te n t in h ib itio n to be c o n te x t-s p e c ific . S tu d ies th at employed a com paratively long ISI sep aratin g CS preexposure from the con d ition in g t r ia l and changed the con text between preexposure to a CS and the CS-US t r ia l have reported a d isru p tio n o f la te n t in h ib itio n with an in te r o c e p tiv e CS paired w ith an in tero c ep tiv e US (Rudy ^ 1977; Westbrook e t a l , 1981) and w ith an ex tero cep tiv e CS paired w ith an in te r o c e p tiv e US (Channell & H a ll, 1983).
These stu d ie s are c o n s is te n t a lso w ith CAT which p o stu la te s th a t a co n textu al change between CS preexposure and co n d itio n in g t r i a l a c ts as an ex tern a l in h ib ito r ( c . f . , Pavlov, 1927) r e sto rin g th e a tte n tio n a l response to the preexposed CS and thereby in crea sin g i t s a s s o c ia b ilit y with a US, CAT, u n lik e the Wagner model which can appeal to s e lf-g e n e r a te d prim ing, i s unable, however, to handle data dem onstrating th a t la te n t in h ib itio n w ith a r e la t iv e ly sh ort ISI sep aratin g a preexposed fla v o u r CS from a flavou r-L iC l p airin g i s not a ffe c te d by a change o f con text between preexposure and con d ition in g p resen ta tio n s o f the flavou r CS (Westbrook jet I 98I ) .
The Pearce and H all model can account fo r the context s p e c if ic it y o f la te n t in h ib itio n when a long in te r v a l sep arates preexposure and con d ition in g p resen ta tio n s of the CS i f one assumes th a t con textu al cues and th e preexposed CS are treated as a co n fig u ra i stim u lu s. Subsequent p resen ta tio n o f the CS in a new con text would then be eq u iv a len t to a new con fig u ra i stim u lu s, with correspondingly high a s s o c ia b ilit y . The assum ption th a t con textu al cues and the preexposed CS are treated as a co n fig u ra i stim u lu s c a lls fo r the Pearce and H all model, however, to p red ict th a t la te n t in h ib itio n should a lso be c o n te x t-s p e c ific when preexposure and con d ition in g p resen ta tio n s o f a CS are separated by only a sh o rt temporal in te r v a l. Unlike the Wagner model which can appeal to the
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