PubMed Health⌕ Search

Biomedical subjects

J D KEEHN

Publications and source records attributed to J D KEEHN.

At least 19 recordsLinked to original sources
PubMed1965

TEMPORAL ALTERNATION IN THE WHITE RAT.

Four white rats were reinforced after 15 then 45 then 15 then 135 (or 5) responses to a bar under a single exteroceptive stimulus condition. Three came to make long pauses before the longest ratio in the schedule but not before any of the others. Four other rats were reinforced after alternate response chains each made on two bars. The first chain was FR5FR5 for all subjects, the second FR5FR40 for two, and FR40FR5 and FR20FR5 for one subject each. Subjects reinforced on schedule mix (chain FR5FR5 chain FR5FR40) both paused longer after the first than after the second chain relatively early in training. Later, the subject reinforced on mix (chain FR5FR5 chain FR40FR5) also paused longer after the first chain, but pauses of the fourth subject were equally short after both chains. When the ratios in the second chain were reversed the two subjects now reinforced on mix (chain FR5FR5 chain FR40FR5) paused much longer after the first chain, but the other two paused only slightly longer after the first than after the second chain.

Discrimination Learning↗
PubMed1960

Licking rates of albino rats.

Local licking rates of eight albino rats, when the rats were given tap water at the end of a short runway after 23 hours of water deprivation, averaged a little over seven licks per second. Small variations within sessions were found, rates being slightly but consistently higher at the beginning than later on in sessions. Inter-session and individual differences were also observed, but were only of theorder of one lick per second. Within practical limits, it appears that licking rates of rats are constant.

Animals↗
PubMed1959

Magnitude of reinforcement and consummatory behavior.

The rates at which white rats licked saline, sucrose, and saccharin solutions, respectively, were measured by cumulative recording of tongue contacts with the solution in question. The local rate of licking was constant for all solutions, but differences in the distribution of sustained periods of licking were related to the type and concentration of the fluid consumed.

Animals↗