Hinson, J. M., & Tennison, L. R. (1999).
Within-session analysis of visual discrimination.
Journal of the Experimental Analysis of Behavior,
72, 385-405.
Within-session changes in responding by pigeons during a
maintained successive discrimination procedure were examined in
four experiments. In the first two experiments, which involved
discrimination of visual flicker rate, within-session changes in
responding were minimal or absent. A third experiment, which
examined discrimination of rectangular forms, demonstrated that
the absence of within-session changes in responding was not
limited to flicker-rate stimuli. A fourth experiment showed that
the absence of within-session changes in responding was not due
to high task difficulty in the previous experiments. For the
group of subjects in each experiment, within-session changes in
responding did not influence discrimination performance.
Therefore, measures of overall response rate accurately
represented responding both within and across sessions. The
occasional appearance of within-session decreases in responding
for a few birds may be attributable to satiation.
Key words: visual discrimination, within-session responding,
dimensional contrast, flicker rate, rectangular form, key peck,
pigeon