Higa, J. J. (1996).
Dynamics of time discrimination: II. The effects of multiple impulses.
Journal of the Experimental Analysis of Behavior,
66, 117-134.
According to a diffusion generalization model, time
discrimination is determined by the frequency and recency of
preceding intervals of time. A procedure for studying rapid
timing was used to investigate whether pigeons' wait-time
responses were sensitive to these factors. In Experiment 1 the
number (two or eight) and spacing (consecutive or far apart) of
5-s interfood intervals (called impulses) intercalated in a
series of 15-s interfood intervals (nonimpulses) were studied.
Experiment 2 was identical to the first but the interfood
intervals were increased by a factor of three. Overall, impulses
shortened wait times in the next interfood interval. However,
several impulses occurring in succession extended the localized
effect of an impulse: Wait times following a set of eight-close
impulses were slow to recover to preimpulse levels. The results
show that linear waiting is only an approximation to the dynamic
process, and a process that is sensitive to events in an animal's
remote past, such as the diffusion generalization model, provides
a better account of rapid timing effects.
Key words: time discrimination, dynamics, diffusion
generalization model, wait time, interfood interval, key peck,
pigeons