The Origins of Music: Preface - Preface

switches to a grunt,will the listener’s interest be revived? If interest is

revived,is this due to an acoustic or semantic difference?

Figure 6.3 provides a schematic illustration of the experimental design.

Test subjects participated in either a within-referent session (habituate

to warble and test with harmonic arch,or the reverse) or a between-

referent session (habituate to warble or harmonic arch and test with

grunt,or the reverse);the identity of the caller was held constant

throughout a session.Different exemplars of one call type were played

until the subject failed to look in the direction of the speaker on two con-

secutive trials.Having habituated,we played back one exemplar from a

different call type category.If the subject responded (interest revived,

subject orients),we ended the session.If the subject failed to respond

(transferred habituation),we ran a posttest trial using an exemplar from

a different call type category.The reason for the posttest trial was to

85 Primate Vocalizations in Emotion and Thought

Figure 6.3

Experimental design for habituation-discrimination playback with rhesus monkey food-

associated calls.In the upper panel,a hypothetical within-referent condition is shown,with

habituation to warbles and then test with harmonic arch.The posttest trial involves a single

playback of a shrill bark.The lower panel shows a hypothetical between-referent condi-

tion,with habituation to grunts and test with a harmonic arch or warble.

Fig.6.3