Pictures, concrete nouns, or abstract nouns were presented sequentially at rates of 5.3 or 2 items/sec, the faster rate being designed to prevent implicit labeling of pictures during input while permitting pictures to be recognized and words to be read. Sequential memory was tested by means of a serial reconstruction task. Consistent with previous findings for immediate memory...
The relationship between the transcephalic DC potential (TCDC) and scotopic critical flicker frequency (CFF) was investigated in two groups of clinically normal male Ss. Comparisons of those Ss shifting in TCDC in a positive direction vs those shifting negatively and/or less positively were made. There was a replicable significant association between negative shifters prior to...
Responding under fixed-interval schedules was studied in three pigeons as a function of three deprivation procedures. Postreinforcement pauses and response rate were measured separately, and quarter-life values were determined. The terminal performance for each bird was characterized by break-and-run patterns of response. Chronic changes in body weight of 5% to 10% of the bird’s...
When a buzzer was used as the discriminative stimulus, atropine sulfate impaired performance of an established SD-S‡ discrimination by increasing response rates during S‡ periods. Atropine methylnitrate did not have this effect, suggesting that the behavioral effects of atropine sulfate resulted from its antagonism of a central cholinergic inhibitory system. The importance of...
Septal lesions alter the nature of social behavior in rats and hamsters. Rats were hyperemotional and more gregarious (contact time) in the open field following septal lesions. Hamsters were neither hyperemotional nor more gregarious after septal lesions. A marked increase in number of aggressive encounters was observed between hamsters.
This experiment attempted to replicate the persistent discrimination (PD) effect and to compare extinction rates and patterns to stimuli which had served as positive (S+) or negative (S−) discriminanda in a discrimination test. Ten albino rats received 176 discrimination trials followed by 80 continuously reinforced trials and 36 extinction trials. The PD effect did not appear...
The experiment examined the effects of three instructed response conditions upon the conditioned blocking of the occipital alpha rhythm: (1) response at light UCS onset, (2) response at light offset, and (3) no response. The results indicated that significant conditioning occurred under all three response conditions when compared to tone blocking habituation during unpaired...
A simplified method of inducing ulceration by stress was applied to two strains of nits selectively bred for high and low emotionality in the open-field test. Contrary to a previous report, the severity of stomach ulceration as assessed by a refined technique of stomach examination was found to be greater in the emotionally reactive strain (MR) than in the nonreactive strain (MNR...
Amount of preliminary bar-press training (25 vs 125 discrete fixed-ratio trials) and amount of noncontingent pre training (0 vs 500 presentations of cues and associated reward magnitudes with the lever retracted) were manipulated factorially prior to contingent discrimination between five- and one-pellet cues. The 500-presentation groups demonstrated differential responding in...
Three groups of mature cats were tested for acquisition of a successive visualpattern discrimination. Ammon’s horn and pyriform cortex of Group 1 (N = 6) had been ablated. Group 2 (N = 4) were sham-operated and Group 3 (N = 3) were intact normal animals. Group 1 was significantly inferior to the combined control groups (p < 0.004). Hence, ablation of the hippocampal region...
Eight albino rats were trained to pull a plunger for water reinforcements that were delivered on several fixed ratios from FR-4 to FR-32. The mean durations of the nonreinforced responses in the FR chain were significantly longer than mean reinforced durations. This differentiation also proved to be labile to exteroceptive stimulus cues.
The behavior of rats receiving constant electrical stimulation of the hippocampus was compared with that of hippocampectomized and unoperated control rats on a task requiring inhibition of a punished approach response. No significant differences appeared in the number of shocks accepted during training although operated Ss showed significantly shorter approach latencies following...
Increasing the delay interval gradually and in small increments produced faster delayed response learning than when the delays were sudden and spanned long intervals. The gradually advanced procedure relative to immediately advanced control procedures resulted in better performance at delays of 8 and 12 sec but not 16 sec. The gradually advanced group also responded with longer...
Four trained Ss participated in a task concerned with intersensory facilitation of reaction time (RT). Discriminative RT to a visual event was longer than discriminative RT to a combined auditory-visual event, even though the auditory event by itself was a catch signal. The magnitude of this difference was greater with a long (5.5 sec) as opposed to short (.5 sec) foreperiod...
Perceptual assimilation was demonstrated with some sets of thermal stimuli. This result is at variance with previous research, which has consistently yielded contrast effects.
Perceptually isolating a CCC by enclosing it in a rectangle improved STM for that item. No residual effects of this isolation were found on following nonisolated items. The possibility of accounting for improved STM of items involving conceptual class change in terms of enhancement through isolation, instead of reduction of semantic interference effects of previous items, was...
Lists of 264 words were studied by 75 Ss. The Ss were divided into three groups instructed to remember either meaning or sound or both meaning and sound of the study words. During recognition, S was required to indicate which word of each test pair had been presented earlier. The incorrect alternative for each test pair was a homophone, synonym, or a word unrelated to the correct...
The effects of paced respiration (PR) and attentive observation (ATT) on heart rate (HR) and finger-pluse amplitude (FPA ) were investigated in adult fem ale Ss. Although HR responses to trial onset were task dependent, accelerating for Group FR and decelerating for Group ATT, temporally conditioned anticipatory HR deceleration was obtained across tasks. Across trials, HR...
Swiss albino mice were trained to take the food from the food magazine in a conditioning chamber. Light for 10 sec acted as a conditioning stimulus. When the mice were fully trained, they were injected intraperitoneally by a brain extract from untrained mice which Puromycin was administered intracranially. After the injection of the extract of Puromycin affected brains, the...
Eight rats were given massive training sessions with spatial probability problems. A noncorrection procedure was used and brain stimulation served as the reinforcer. Results indicate no clear response strategy with only one rat showing clear and consistent maximizing.
Male mice were housed either in wire-mesh cages placed adjacent to one another or in similar cages separated by wooden partitions. A higher level of adrenocortical function, measured by relative adrenal weights and adrenal ascorbic acid depletion, was found in the mice which had been allowed partial social contact. These results demonstrate that the adrenal cortex not only...
Pigeons were trained consecutively on two simultaneous visual discriminations. For half the Ss, the dimension relevant in the first problem remained relevant in the second (intradimensional shift); for the remainder, the dimension irrelevant in the first problem became relevant in the second (extradimensional shift). As is predicted by two-stage theories of discrimination...
Three groups of rats (C, D, and E) each received, during a daily session, two runway trials in one-half of a differential conditioning apparatus to one-pellet reward. Groups C and E also received one and 12 pellets, respectively, in a placement cage twice during a session. Group D received two additional 12-pellet trials in the other half of the differential conditioning...
In a 6-ft runway, rats were given 15 shock-escape trials, or none, followed by various transfer conditions. Shock-escape followed by thirst-motivated training resulted in response suppression which was unaffected by a view of water from the runway, was not due to reduced attraction to water, and was not an exclusive function of prior shock experience.