Kinetic assessment of the effects of task difficulty, microencephaly, and a response manipulandum alteration on the rate of fixed-ratio discrimination acquisition.
Fixed-ratio discrimination (FRD) training session-accuracy curves were constructed using first-order, nonlinear regression and probit analyses to determine maximal (asymptotic) accuracy and the number of sessions required to reach half-maximal accuracy. Increased FRD difficulty (reductions in the differences between the 2 fixed-ratio values to be discriminated) and a training parameter change each increased the number of sessions required to reach half-maximal accuracy and decreased maximal FRD accuracy (i.e., session-accuracy curves were shifted down and to the right) regardless of analysis procedure. These findings indicate that the above manipulations induced mixed competitive-noncompetitive inhibition of the rate of FRD learning. Microencephalic rats were more sensitive to increases in FRD difficulty, whereas control rats were more sensitive to the training parameter change.
Tessel
Richard E
RE
Department of Pharmacology and Toxicology, University of Kansas, School of Pharmacy, Lawrence 66045-2505, USA. tessel@dole.lsi.ukans.edu
Loupe
Pippa S
PS
Schroeder
Stephen R
SR
Schloss
John
J
D000818:Animals; D001522:Behavior, Animal; D004193:Discrimination Learning / Q000187:drug effects / Q000502:physiology*; D005260:Female; D007700:Kinetics; D008746:Methylazoxymethanol Acetate / Q000031:analogs & derivatives* / Q000494:pharmacology; D008831:Microcephaly / Q000139:chemically induced / Q000503:physiopathology*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D012055:Reinforcement Schedule; D013647:Task Performance and Analysis; D013723:Teratogens / Q000494:pharmacology
D013723:Teratogens; D008746:Methylazoxymethanol Acetate; C030667:methylazoxymethanol