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1.
Pigeons were trained on an operant procedure to discriminate between morning and afternoon when location did not vary (Experiment
1). The pigeons were placed on a fixed interval (FI) schedule in the morning and on a different FI schedule in the afternoon.
Probe trials that occurred at the beginning of the training sessions were examined. The pigeons responded differently, depending
on the time of day, reflecting the learning of a stable 24-h memory representation of the association between the FI schedules
and the time of day. The pigeons from Experiment 1 were then clock shifted and tested twice, to determine whether they were
relying on an endogenous circadian oscillator, an hourglass mechanism influenced by the photoperiod, or environmental noise
to make the time-of-day discrimination (Experiment 2). The results of the second experiment indicated a circadian mechanism
was most important for the observed time-of-day learning. 相似文献
2.
Rats (n=4) searched for food on an eight-arm radial maze. Daily 56-min sessions were divided into eight 7-min time zones, during
each of which a different location provided food; locations were randomized across subjects before training. The rats obtained
multiple pellets within each time zone by leaving and returning to the correct location. Evidence that the rats had knowledge
about the temporal and spatial features of the task includes the following. The rats anticipated locations before they became
active and anticipated the end of the currently active locations. The rats discriminated currently active locations from earlier
and forthcoming active locations in the absence of food transition cues. After the rats had left the previously active location,
they visited the next correct location more often than would be expected by chance in the absence of food transition cues.
The rats used handling or opening doors as a cue to visit the first location and timed successive 7-min intervals to get to
subsequent locations. 相似文献
3.
The effects of food reward on rats’ behavior in radial and Dashiell tunnel mazes were examined in two experiments. In the first, with animals at ad-lib body weights, food reward reduced speed of movement at the food locations, but did not affect the patterns of movement in either maze. Exploratory efficiency in the Dashiell maze was unaffected by food reward, and spontaneous patrolling of the radial maze by the nonrewarded animals was comparable to the behavior, reported by others, of rats running for food reward on elevated eight-arm mazes. In the second experiment, with subjects maintained at 80% of ad-lib body weights, there was some evidence for “winstay” learning: food-rewarded rats in the Dashiell maze were relatively more active near the food locations than were the nonrewarded animals, and more rewarded than nonrewarded rats revisited all food locations in the radial maze. Nonetheless, exploratory efficiency in the Dashiell maze was unaffected by food reward, as was patrolling efficiency in the radial maze, which was again comparable to that of rats on elevated mazes. The similarity in behavior of rewarded and nonrewarded animals in these mazes implies that the major determinant of their behavior, whether or not food reward is provided, is a spontaneous tendency to avoid places recently visited. 相似文献
4.
《Mind, Brain, and Education》2017,11(1):10-20
Children tend to sleep and wake up early and to exhibit daytime sleep episodes. To evaluate the impact of school start times on sleepiness and attention in preschool children, this study compared the temporal patterns of sleep, daytime sleepiness, and the components of attention between children aged 4–6 years that study in the morning (n = 66) and the afternoon (n = 144) shifts. The former get up 1 hr and 30 min earlier on weekdays and show lower efficiency on the sustained attention task than those who study in the afternoon. Thus, the morning shift was associated with a reduction in nighttime sleep, which might have a negative effect on children's performance in the morning, causing higher levels of daytime sleepiness and a decline in sustained attention. Because only one parameter of one component of attention was negatively affected, further studies are needed to confirm this effect on cognition. 相似文献
5.
Twenty domestic Muscovy ducks were trained to traverse a runway for food reward. Subjects were then randomly assigned to treatments. In one treatment, subjects received six nonrewarded trials followed by six rewarded trials every day for 12 days; and, in the other treatment, subjects received six rewarded trials followed by six nonrewarded trials every day for 12 days. These successive acquisition and extinction (SAE) treatments were selected because different extinction rates on the nonrewarded trials are expected on the bases of previous research performed with rats. Analyses of variance revealed the former treatment yielded significantly greater resistance to extinction than did the latter treatment. It was concluded that ducklings performed similarly to rats in the above SAE situation. 相似文献
6.
The objective was to determine whether rats could learn to time a 48-h interval. Rats (n = 6) were continuously housed in operant chambers in constant darkness. The feeding cycle consisted of unlimited access to
food for 6 h, followed by 42 h without access to food (i.e., meals were available on alternate days, contingent on breaking
a photobeam in the food trough). Head entries into the trough increased as a function of time prior to the meal; this increase
was higher, relative to the increase that occurred at the same time of day on alternate (i.e., nonfood) days. These data suggest
that rats discriminated alternate days. Next, two meals were omitted to dissociate mechanisms of a self-sustained endogenous
rhythm, interval timing, and alternation. Response rate increased periodically every 24 h, which suggests that the rats anticipated
alternate days by discriminating the status of the previous day as a meal or a nonmeal day. 相似文献
7.
Two theories that have been hypothesized to mediate acquisition in daily time–place learning (TPL) tasks were investigated in a free operant daily TPL task: the response cost hypothesis and the species-typical behavior hypothesis. One lever at the end of one of the choice arms of a T-maze provided food in the morning, and 6 h later, a lever in the other choice arm provided food. Four groups were used to assess the effect of two possible sources of response cost: physical effort of the task and costs associated with foraging ecology. One group was used to assess the effect of explicitly allowing for species-typical behaviors. If only first arm choice data were considered, there was little evidence of learning. However, both first press and percentage of presses on the correct lever prior to the first reinforcement revealed evidence of TPL in most rats tested. Unexpectedly, the high response cost groups for both of the proposed sources did not perform better than the low response cost groups. The groups that allowed animals to display species-typical behaviors performed the worst. Skip session probe trials confirmed that the majority of the rats that acquired the task were using a circadian timing strategy. The results from the present study suggest that learning in free operant daily TPL tasks might not be dependent on response cost. 相似文献
8.
Masato Ishida 《Learning & behavior》1986,14(3):293-300
When extinction is delayed very long, the superior resistance to extinction of the random schedule group relative to the alternating schedule group disappears (partial reinforcement delayed extinction effect, PRDE). Two experiments assessed the effects of reinforcement/nonreinforcement on Trial 1 on the PRDE. Following extended partial reinforcement acquisition training in a runway, rats received extinction training after a short (1-day) or long (23-day) retention interval. The schedules used in Experiment 1 were: a single-alternation (SA) schedule beginning each day with a rewarded (r) trial, for Group r-SA; an SA schedule beginning with a nonrewarded (n) trial, for Group n-SA; and a random (Rd) schedule, for Group Rd. The schedules and group names used in Experiment 2 were r-SA, Rd, and r-Rd. The results were that (1) rats given r-SA schedules yielded considerable resistance under delayed extinction, (2) those given Rd and r-Rd schedules showed a decline in resistance to extinction over a long retention interval, (3) those given the n-SA schedule showed relatively low resistance at both retention intervals, although retention deficit was not greater than in the case of the Rd schedule, and thus, (4) the PRDE was found in both experiments, although only weakly in Experiment 1. The results indicated that a regularly alternating reward pattern was a more important determinant than was type of reward on Trial 1 for the PRDE. The PRDE due to differential retention deficits among schedules is discussed on the basis of dual-process associative sequential mechanisms and cognitive rule-encoding mechanisms. 相似文献
9.
Rats (n=6) visited four baited locations (randomly chosen on each trial; study phase), one of which was randomly selected to provide
chocolate. After short (1-h) or long (25-h) retention intervals (RIs), eight locations were available, and the four locations
not available in the study phase provided food (test phase); the chocolate location also provided food after long RIs. More
visits to the chocolate location occurred after long RIs than after short RIs. Next, chocolate was paired with LiCl during
the long RI (i.e., after encoding the chocolate location). Fewer revisits to the chocolate location occurred after LiCl than
in previous testing with the long RI. The rats demonstrated complete transfer when grape replaced chocolate after LiCl-chocolate
pairing. The discrimination of what, when, and where could not be based on adopting different revisit strategies at different
times of testing. 相似文献
10.
Charles I. Brooks 《Learning & behavior》1980,8(1):143-151
Four experiments compared runway extinction or hurdle-jumping from nonreward performance following brief (10 trials) continuous or partial reinforcement acquisition. Some of the partial groups received all nonrewarded trials prior to any rewards. The major findings were that (l) rats receiving all nonrewarded experiences prior to rewarded ones were more persistent during extinction than continuously rewarded subjects; (2) rats receiving nonrewarded placements prior to rewarded ones in one compartment of a two-compartment box, failed to learn a hurdle-jumping response to escape nonreward, whereas rats not receiving the initial nonrewards did learn the escape response; (3) increasing the number of rewarded placements following initial nonrewarded ones offset the effect noted in (2). The results, which are discussed in the context of a frustration analysis of the small-trials partial reinforcement effect, suggest that incentive growth over rewarded trials is retarded when the rewards have been preceded by nonrewards. The similarity of these results to those investigating the phenomenon of latent inhibition is apparent, and possible mechanisms responsible for the present results are suggested in current theoretical accounts of latent inhibition. 相似文献
11.
INTRODUCTION Left ventricular hypertrophy has been thought to be the principal predicators of predisposing risk factor of cardiac morbidity and mortality (Devereux, 1995; Levy et al., 1990). The pathogenesis that mediates cardiac hypertrophy is poorly understood. Cardiachypertrophy can be induced by hemodynamic over-load, ischemic disease, neurohumoral factors and intrinsic defects in cardiac structural protein genes (Sadoshima and Izumo, 1997; Vikstrom and Lein-wand, 1996). Another in… 相似文献
12.
Many characteristics of a series of discrete independent hedonic events may be remembered by rats in terms of, for example, how many events were rewarded and how many were nonre-warded. Such memory for multiple hedonic events, which has been shown to be a potent factor controlling instrumental responding, was examined here in five investigations employing serial anticipation learning in a runway. It was found that the ability of rats to remember the hedonic events reward and nonreward is highly developed, accurate, and quite resistant to forgetting and interference. Rats not only remembered a rewarded event and a nonrewarded event, but they also remembered the order in which the two events occurred. Rats remembered how many nonrewarded events there had been accurately enough to suggest that they were using some form of a counting mechanism. Rats exhibited little forgetting of eight prior discrete hedonic events, one rewarded followed by seven nonrewarded, even when these occurred over an interval of 20 min and involved considerable potential interference. In the serial learning situation employed here, marked primacy effects were obtained, earlier nonrewarded trials in a series being better anticipated than later ones. The primacy effect was found to depend upon the type of series employed. By assuming that stimulus generalizations occur between the multiple hedonic events remembered by rats, all anticipatory learning obtained here could be explained in considerable detail. 相似文献
13.
Rats were runway-trained in a variety of serial discriminations that involved three different reward outcomes: Noyes pellets (R), a Kellogg’s Corn Pop (R’), and 30 sec of confinement in an unbaited goal area (N). Each of three groups experienced a series that consisted of a single non-rewarded trip down the runway, irregularly mixed with a longer series that for one group (n = 3) consisted of three trips rewarded with the pellets, followed by a terminal nonrewarded trip (RRRN/N). A second group (n = 6) had the single N series mixed with a series that included an initial trip rewarded with a Pop, and three subsequent trips rewarded with pellets, pellets, and nothing, respectively (R’RRN/N). The remaining group was trained with an RRN/N series pair. The interval between trips within a series was about 20 sec, and the interval between series was about 10 min. All rats developed strong, accurate anticipation of the terminal nonreward event of the longer series. In a 4-day transfer shift phase, a matched one-half of the rats originally trained R’RRN/N were shifted to a new series pair, RRRN/NRRRN, as were all the animals trained RRN/N. The remaining one-half of the matched rats were shifted to RRN/NRRN, as were the animals originally trained on the RRRN/N series pair. The transfer to the new series was plainly more powerful in animals initially trained with the R’RRN series than it was in either of the control groups. This shift result is taken to mean that rats classified the differing motivational events of the R’RRN series into at least three numerical categories: (1) one R’, (2) two Rs, and (3) three rewards. 相似文献
14.
The study investigated the effects of participation in the activities of Science-A Process Approach (SAPA) on the oral communication skills of disadvantaged kindergarten children. Experimental-control group, pretest-posttest research design was employed. The investigator designed the Test of Oral Communication Skills (TOCS) to measure students' oral communication skills. Two experimental groups (one morning and one afternoon, N = 52) and two control groups (one morning and one afternoon, N = 48) were randomly assigned from two kindergarten classrooms (morning and afternoon classes in each) in an inner-city school in Columbus, Ohio. The investigator provided the science instruction to all students. Experimental subjects received 22 half-hour lessons from exercises a through k of Part A, SAPA. Control subjects received 22 lessons from Springboards to Science, a teacher demonstration, class discussion type of kindergarten curricuoum used in the school system. The treatment period spanned 12 academic weeks. Analysis of variance of TOCS pretest scores showed no significant differences among any of the means of the four groups. Analysis of covariance of TOCS posttest scores revealed differences significant at .05 or beyond in the mean scores of the experimental groups and control groups for total oral and total receiving skills and for six of the eight subskills measured by TOCS. Application of the Tukey (b) test revealed that experimental group mean scores exceeded control group mean scores in every TOCS skill and subskill area and that in total oral transmitting subskills both experimental group mean scores were significantly greater at .05 level or beyond than corresponding mean scores for both control groups. Within the parameters of this study, it may be concluded that when the activities and teaching strategies of SAPA curriculum are presented to disadvantaged kindergarten children, their oral communication skills, especially the transmitting (speaking) skills, are clearly enhanced. 相似文献
15.
Steven J. Haggbloom 《Learning & behavior》1982,10(1):61-64
Three groups of 12 rats received 25 pretraining trials to each future discriminandum employed in a subsequent differential brightness conditioning problem. Groups NR and RN received partial reinforcement (PRF) pretraining either with or without, respectively, transitions from nonrewarded to rewarded trials (N-R transitions). Group CRF received consistent reinforcement during pretraining. A fourth group (n=12), Group NP, received no pretraining. During discrimination learning, one-half of the rats in each group received all their daily S+ trials preceding their daily S? trials (+? sequence); the remainder of the rats received an intermixed sequence of trials to S+ and S? (+?+ sequence). Discrimination learning was faster under the +? sequence than under the +?+ condition, and discrimination learning was retarded in Group NR relative to the other three groups, which did not differ from one another, under both the +? and +?+ discrimination sequence conditions. The results are discussed with Reference to previous experiments demonstrating N-R transition effects on discrimination learning, a theoretical extension of sequential theory to discrimination learning, and the effects of nondifferential reinforcement prior to discrimination learning on learned irrelevance. 相似文献
16.
In Experiment 1, a group of rats were runway trained on each of two reward series for 32 days. The two series consisted of three runs, the first two of which were, respectively, rewarded and nonrewarded; the third run was rewarded in one series but nonrewarded in the other. A 40-min interval separated the two series; the first and second runs within the series were separated by a 10-min interval, whereas the second and third runs were separated by a 30-sec interval. The reward (and nonreward) events and temporal cues of the two series are designated R-NR/R-NN. A second group was similarly trained, with the exception that the 10-min interval separated the second and third runs (RN-R/RN-N). Both groups developed appropriate differential running on the third run of the two series, and the RN-R/RN-N animals ran appropriately (slowly) on the second run of both series. Appropriate Run 2 performance appeared in one half of the R-NR/R-NN animals (depending upon order of series presentation); the remaining half ran faster on Run 2 of the R-NR series than on the same run of the R-NN series, an effect currently termed interevent anticipation. A cue shift phase in which all within-series intervals were 30 sec showed that the temporal intervals were controlling performance before the shift. Experiment 2 showed that interevent anticipation appears when all within-series intervals are either 10 min or 30 sec from the beginning of training, suggesting that the elimination of interevent anticipation in Experiment 1 was due to the differential cuing of runs by the temporal intervals rather than the particular interval duration. The overall findings suggest that the similarity of Run 2 and Run 3 performance termed interevent anticipation may be due to a failure to discriminate the ordinal position of runs within a series. 相似文献
17.
Rats were trained to forage for food on a four-arm radial maze. Each arm of the maze was defined as a patch and contained four feeding stations. Each patch contained a total of 20 45-mg food pellets, with the first feeding station in each patch baited with 1 pellet and the remaining stations baited with 1, 5, or 13 pellets. In Experiment 1, one group of rats was tested with feeders open and food readily accessible, and another group was tested with metal covers on the feeders, which necessitated extra time to gain access to food. With open feeders, the rats visited each feeder in a patch in the order in which they encountered the feeders, from the center of the maze to the end of the arm. The rats in the group with the covered feeders often visited the feeders containing 5 or 13 pellets first and the feeders containing 1 pellet last. In Experiment 2, it was found that the rats switched readily between these two foraging strategies when tested with covered and open feeders on alternate sessions. The extra time and effort required to uncover food appeared to produce selective foraging in rats. 相似文献
18.
Tâmile Stella Anacleto Taísa Adamowicz Laura Simões da Costa Pinto Fernando Mazzilli Louzada 《Mind, Brain, and Education》2014,8(4):169-174
Although the environmental light/dark cycle is the main zeitgeber for the human species, the social cues seem to be important in the synchronization of circadian rhythms. In Brazil, the existence of two school schedules—one with only morning classes (MG) and other with only afternoon classes (AG)—allows the investigation of the effect of school activities on light exposure and sleep/wake patterns in children. Forty‐seven children wore wrist actimeters for a week for registration of light and sleep data. MG children presented shorter sleep duration on school days than the children from the AG. The results showed that during school days MG children were exposed to bright light earlier in the morning when compared to AG children. Nevertheless, there were no differences in light exposure after sunset. The results reflect the role of school schedules and artificial light in shaping light exposure, and its association with sleep timing in children. 相似文献
19.
Douglas Reberg 《Learning & behavior》1980,8(1):120-128
Four pairs of rats were studied in a yoked control design intended to determine if an interim activity (schedule-induced drinking) was sensitive to operant contingencies. Food was always presented on a fixed-time 30-sec schedule. Additionally, a positive or negative operant contingency was in effect during the first 6 sec of each interval. The positive (drink/food) contingency produced an extra food presentation at the 6th second of an interval if the lead rat drank at least once in the first 6 sec. The negative (no-drink/food) contingency produced an extra food presentation only if the lead rat did not drink in the first 6 sec. Two pairs of rats were first exposed to the positive contingency and then to the negative contingency. Two pairs received training in the reverse order. In drink/food training, all lead rats developed patterns of drinking that produced extra food presentations in most intervals. There were some indications that the positive contingency facilitated early acquisition of drinking, but the yoked rats eventually developed temporal distributions and asymptotic levels of drinking comparable to those that occurred in lead rats. In no-drink/food training, the two lead rats initially exposed to the positive contingency showed high levels of drinking inappropriate to the negative contingency, but the two lead rats initially exposed to the negative contingency showed appropriately low levels of drinking. The latter effects seem attributable to the no-drink/food contingency. 相似文献
20.
The Impact of Instructional Design on College Students’ Cognitive Load and Learning Outcomes in a Large Food Science and Human Nutrition Course 
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下载免费PDF全文 Jeanette Andrade Wen‐Hao David Huang Dawn M. Bohn 《Journal of Food Science Education》2015,14(4):127-135
The effective design of course materials is critical for student learning, especially for large lecture introductory courses. This quantitative study was designed to explore the effect multimedia and content difficulty has on students’ cognitive load and learning outcomes. College students (n = 268) were randomized into 1 of 3 multimedia groups: text + graphics (Group 1–TG); audio + text + graphics (Group 2–ATG); or video + audio + text + graphics (Group 3–VATG). Participants answered a demographic survey and pretests before viewing 2 food science supplemental lecture materials (i.e., water mobility and amino acid structures) and completing the cognitive load instrument and post‐tests within a noncontrolled setting. Cognitive load scores were tabulated and compared using a 3 × 3 ANOVA and Tukey post hoc analysis across multimedia groups and food science supplemental lecture materials. Based on the post hoc, students in Group 1–TG had higher intrinsic cognitive load scores than Group 2–ATG (ANOVA, P < 0.05). Cognitive load and post‐test scores were tabulated and compared using a spearman correlation across groups. In Group 1–TG, students that reported less intrinsic cognitive load had higher post‐test scores. Also, students that reported more germane cognitive load had higher post‐test scores. In Groups 2–ATG and 3–VATG, students that reported less extraneous cognitive load had higher post‐test scores (ANOVA, P < 0.05). 相似文献