In conscious Wistar rats neuromuscularly paralysed by gallamine, operantly conditioned reduction of heart rate was achieved under both negative and positive reinforcement schedules using the tail shock avoidance or the rewarding brain-stimulations in 20-min test sessions. The primary aim was to assess whether it would be possible to achieve operant conditioning of the heart rate, evoked not as ...

The cross section of the process e+e− → ωπ0 → π0π0γ has been measured in the c.m. energy range 920–1380 MeV with the CMD-2 detector. Its energy dependence is well described by the interference of the ρ(770) and ρ(1450) mesons decaying to ωπ. Upper limits for the cross sections of the direct processes e+e− → π0π0γ, ηπ0γ have been set.

Foods that are rich in fat and sugar significantly contribute to over-eating and escalating rates of obesity. The consumption of palatable foods can produce a rewarding effect that strengthens action-outcome associations and reinforces future behavior directed at obtaining these foods. Increasing evidence that the rewarding effects of energy-dense foods play a profound role in overeating and th...

Four appetitive Pavlovian conditioning experiments with rats examined the rate at which the discrimination between compounds AY and AX was solved relative to the discrimination between compounds AY and BY. In Experiments 1 and 2, these discriminations were preceded by training in which A and B were continuously reinforced and X and Y were partially reinforced. Consistent with the Pearce and Hal...