Maze-learning Ability Research Articles

Effect of different rearing condition on early age in the maze, open-field, and aversive behaviours in the dairy cow during the first lactation

The aim of the study was to tested hypotheses that the primiparous cow’s behaviour is impacted by the method of rearing from the second day of life to weaning. 53 Holstein primiparous cows were used. They were reared in different ways during milk nutrition. Calf-heifers were assigned to one of five rearing groups on the second day after having nursed their mothers for 24 hours: H) hutch; HA) hutch, from 7 days pen with an automated drinking machine (ADM); MA) with mother, from 7 days pen with an ADM; MH) with mother, from 7 days hutch; MN) with mother, from 4 days with nursing cows. After weaning (56 days), all heifers were kept in group pens, after calving in free-stall housing. Maze learning ability was tested in the third month of lactation. In the 5th month, cows were observed in the open-field, in the seventh month they were subjected to an aversion test (AT). Group MN was the slowest in solving all tasks and HA the fastest. Differences were recorded among groups in the first-day evaluation (P < 0.01). No differences in open field tests were found. In the AT traversing, the slowest were groups H and HA, the fastest MH and MA (P < 0.01). The time of the first return was different (P < 0.001). On the first day, the most vocalized cows of the MN group (P < 0.05). The results show that the method used to rear heifers may have a significant impact on their maze and aversive behaviour.

The Maze-Learning Ability of Blind Compared with Sighted Children

The Maze-Learning Ability of Blind Compared with Sighted Children

The effects of electroacupuncture on the synaptic structure of hippocampal CA3 neurons and learning and memory ability after cerebral infarct

Objective To evaluate the effects of electroacupuncture (EA) on synaptic interface structures around a cerebral infarct and evaluate how learning and memory relate to synoptic structure. Methods Forty-eight male, adult Wistar rats were divided randomly and equally into an EA group and a control group after models of ische-mic brain injury had been established. Each group was then divided into 1 week, 2 week and 3 week sub-groups. In the EA group EA was started 24 hours after the operation at the Baihui (DU20) and Da Zhui (BUI4) points and continued for one week, two weeks or three weeks. The control group was fed in normal cages and had no special treatment. Synoptic substructures in the hippocampal CA3 area of the ischemic side were assessed morphologically and quantitatively. Results The synaptic curvatures and postsynaptic density (PSD) an well as the width of the ac-tive area increased significantly in the EA group compared with the control group. Morris water maze learning ability in the EA group exceeded that in the control group. Spatial probe test results also significantly improved in the EA groups compared with the control groups. Conclusions Learning and memory improved in the injured rats following EA, and this is likely to be related to synaptic changes and synaptic plasticity increasing. Key words: Electroacupuncture; Cerebral infarction ; Learning and memory ; Synoptic substructures; Rata

Dietary Phosphatidylcholine Improves Maze-Learning Performance in Adult Mice

The effect of phosphatidylcholine (PC) on maze-learning performance was investigated in adult mice. Three-month-old mice were given a semipurified diet of 1%, 2.5%, or 5% PC over a period of 4 months, with their maze-learning ability assessed beginning at 3 months after the start of the experiment and again 4 and 8 days later. This entailed the measurement of the time required by the mice to reach the maze exit and counting the number of times that mice strayed into blind alleys in the maze. During trial 1, mice in the 5% PC diet group required significantly less time to reach the maze exit compared with the control group (P < .05), while mice in the 1% and 2.5% PC dietary groups tended to require a shorter time to find the exit, but the differences were not significant. The number of times that mice strayed into blind alleys in the maze was significantly fewer in the 2.5% and 5% PC diet groups than in the control group during trial 1 (P < .05). The PC diets increased the percentages of docosahexaenoic and arachidonic acids in serum but had a lesser effect on brain fatty acid composition. These results suggest that the intake of 5% PC diet improves learning ability in adult mice and that the improved brain function may be related to the provision of choline.

Effect of intake period of docosahexaenoic acid on maze‐learning ability in mice

Male mice (3 mo old) were fed a diet containing 2% docosahexaenoic acid (DHA) plus 3% palm oil or a diet containing 5% palm oil for different periods of time. Maze-learning ability was assessed at 1 and 2 wk and 1 and 3 mo after the start of the experiment. The time required to reach the maze exit and the number of times that a mouse strayed into blind alleys in the maze were measured in three trials, one every 4 d. After the last learning test, all mice were killed and the fatty acid compositions of plasma and brain were determined. There were no significant differences in the maze-learning tests between mice fed the diets at 1 and 2 wk in any of the three trials. After 1 and 3 month, the DHA diet group required less (p<0.05) time to reach the maze exit and strayed into blind alleys (p<0.05) fewer times than the palm oil diet group. Significantly greater DHA levels were observed in the plasma and brain lipids of the mice fed the DHA diet after 2 wk, compared to those fed the palm oil diet (p<0.05), which was compensated for by lower arachidonic acid levels. There were no significant differences in brain DHA levels among mice fed the DHA for 2 wk, 1 mo, or 3 mo. Improved maze-learning ability after DHA intake was evident at 1 mo after the start of feeding and was maintained up to 3 mo, whereas the increased DHA levels in brain were apparent after feeding for just 2 wk. These results suggest that it may take some time after the incorporation of DHA in the brain to develop learning ability in mice.

Effect of Erabu sea snake Laticauda semifasciata oil intake on maze-learning ability in mice

: The oil of Erabu sea snake Laticauda semifasciata, a marine reptile, is used as a health promoting food in Japan. The aims of the present study were to determine the effect of Erabu sea snake oil on the learning ability in mice. Male mice (6 months old) were fed a diet containing 5% lard, 5% Erabu sea snake oil, or 5% fish oil mixture, containing the same percentages (12.8%) of docosahexaenoic acid as the sea snake oil. Maze-learning ability was assessed 4 months after the start of the experiment and the brain fatty acid composition was measured after 4.5 months. In the third trial run of the maze-learning task, the number of times that a mouse strayed into blind alleys in the maze was significantly lower in the sea snake and fish oil mixture groups than in lard group. These results suggest that sea snake oil exerts an equivalent influence on the learning ability in mice to that of fish oil.

The sliding window correlation procedure for detecting hidden correlations: existence of behavioral subgroups illustrated with aged rats

We developed the sliding window correlation procedure in order to examine populations for possible heterogeneity in the ways two variables are related with each other. This procedure involves computing correlation coefficients ( R) for overlapping successive segments of the covariate scores. The distribution of resulting Rs reveals fluctuations in the degree and direction of R over the sample of ranked scores. This procedure is applied to behavioral data of aged rats, which were rank-ordered according to water maze performance, and correlated with open field exploration and conflict behavior in a light/dark chamber. Results revealed correlation coefficients of varying magnitudes and opposing directions for different segments of the population, which were obscured by overall correlation analysis. E.g. for the superior learners, the Rs were highest between maze learning ability, increased open field exploration and reduced anxiety in the conflict test, whereas for the intermediate learners the Rs were highest for maze learning ability related with reduced exploration and increased anxiety. Thus, the sliding window correlation distribution can be applied in conjunction with overall correlation analysis to provide information about the potential presence and locations of subgroups within a population, especially if overall correlation analysis does not yield significant results.

Dose-Response Effect of Egg-Phosphatidylcholine on Maze-Learning Ability and Fatty Acid Composition of Plasma and Brain in Aged Mice Fed an n–3 Fatty Acid-Deficient Diet

Background/Aims: We investigated the dose-response effect of egg-phosphatidylcholine (PC) on the maze-learning ability and brain fatty acid composition in aged mice. Method: Male Crj:CD-1 mice aged 18 months were fed the following diets for 4 months: (i) 5 g palm oil/100 g diet (n–3-deficient control group); (ii) 1 g egg-PC/100 g diet plus 4 g palm oil/100 g diet (egg-PC 1% group); (iii) 2.5 g egg-PC/100 g diet plus 2.5 g palm oil/100 g diet (egg-PC 2.5% group), and (iv) 5 g egg-PC/100 g diet (egg-PC 5% group). Maze-learning ability was assessed 3 months after the start of the experiment. All animals were maintained on the n–3 fatty acid-deficient diets to examine the direct effect of egg-PC on maze behavior. The time required to reach the maze exit and the number of times that a mouse strayed into blind alleys in the maze were measured in 3 trials every 4 days. Results: Our results showed that the 2.5 and 5% egg-PC groups needed less (p < 0.05) time to find the exit and strayed into blind alleys fewer times (p < 0.05) than the control group. In order to determine the relationship between maze-behavior and brain docosahexaenoic acid (DHA) and arachidonic acid (AA) levels in aged mice fed various doses of egg-PC, the plasma and brain fatty acid composition was examined. Dose-response increases in the percentage of DHA were found in plasma lipids. However, based on our data on the brain fatty acid composition of mice fed various doses of egg-PC, no significant differences in the percentages of DHA and AA among the dietary groups were observed. Conclusion: These results suggest that the intake of egg-PC improves maze-learning ability in aged mice fed n–3 fatty acid-deficient diets but it does not influence the percentage of brain DHA and AA.

Residential maze as a task for testing rats' maze learning ability: effects of hippocampal lesions and cholinergic receptor antagonists.

We investigated whether rats can learn mazes by a procedure in which rats were left in the maze (residential maze) in groups for 1 h a day. Water and food locations, which served as the start and goal boxes respectively in the test trial, were at the opposite ends of the maze. On the test trial conducted everyday before the residence period, animals put in the start box showed a significant decrease of the error response into the blind alleys and running time to reach the goal box. Systemic administration of scopolamine (0.25, 0.5 mg/kg), a muscarinic receptor antagonist, dose-dependently increased the number of errors, but mecamylamine, a nicotinic receptor antagonist, had no effect. Bilateral hippocampal lesions retarded both the acquisition and retention of this maze learning. The results suggest that this residential maze procedure is useful for testing maze learning ability in rats.

Dose-response effect of docosahexaenoic acid ethyl ester on maze behavior and brain fatty acid composition in adult mice.

The dose-response effect of dietary docosahexaenoic acid (DHA, 22:6 n-3) ethyl ester (EE) on maze-learning ability in mice was studied. Male Crj:CD-1 mice aged three months were fed a) a diet containing 5 g palm oil/100 g diet (control group); b) a diet containing 0.5 g DHA ethyl ester/100 g diet plus 4.5 g palm oil/100 g diet (DHA-EE 0.5% group); c) a diet containing 1 g DHA ethyl ester/100 g diet plus 4 g palm oil/100 g diet (DHA-EEE 1% group); d) a diet containing 2 g DHA ethyl ester/100 g diet plus 3 g palm oil/100 g diet (DHA-EE 2% group) for four months. Maze-learning ability was assessed three months after the start of the experiment. The time required to reach the maze exit and the number of times that a mouse strayed into blind alleys in the maze were measured in three trials, performed every four days. In trial 1, the DHA-EE 0.5%, 1% and 2% groups required less (p < 0.05) time to reach the maze exit, and the DHA-EE 2% group strayed (p < 0.05) into blind alleys fewer times than the control group. In trial 3 performed four days after the second trial, the DHA-EE 2% group needed less (p < 0.05) time to find the exit and spent a fewer (p < 0.05) number of times in blind alleys than did the control group. In the total lipids of plasma and brain of mice fed DHA, increasing intakes of DHA resulted in an increase in DHA levels, with a corresponding decrease in arachidonic acid (20:4 n-6). Improved maze-learning ability in mice fed DHA-EE 2% was associated with higher DHA levels in brain. Our resulted suggest that there are no linear dose-response effects of DHA on maze-learning ability, however, the intake of DHA-EE 2% diet improves learning ability in adult mice as demonstrated by maze performance.

A relation between maze performance and increased ethanol intake in Long–Evans rats

In addition to the neurochemical and genetic basis of high ethanol consumption, there has been renewed interest in studying the role of behavioral variables and their relation to ethanol consumption. The present study was designed to assess whether a relation exists between a behavioral variable such as maze learning ability and ethanol consumption. Sixty, male, Long–Evans rats, exposed to food and water ad libitum, were given a daily trial in a complex, 16-arm T-maze for 19 consecutive days. The number of errors and time to complete the maze were monitored. Individual maze variable scores were transformed and then combined to allot each animal with an index of overall maze performance, with a smaller maze index score denoting good performance. After completion of maze testing, animals were given alternate-day, free-choice presentations of water and ascending doses of ethanol solutions (2%–10%), followed by a 10-day maintenance period with 10% ethanol. Animals were subsequently separated into two groups of high and low drinkers to examine any relation between differential ethanol intake and maze performance. A significant negative correlation between maze index and ethanol intake for the high drinkers group indicated that a smaller maze index was related to increased ethanol intake. No significant correlation was obtained for the low drinkers group. These results seem to indicate that individual variation in learning ability seems to be related to increased ethanol intake. Thus, innate learning processes may be a relevant trait when one attempts to understand the behaviors related to ethanol intake and preference.

Changes in Maze Behavior of Mice Occur after Sufficient Accumulation of Docosahexaenoic Acid in Brain

The relationship between the time of intake of docosahexaenoic acid [DHA, 22:6(n-3)] and maze behavior in mice was studied. Male Crj:CD-1 mice (3 mo old) were fed a diet containing 2 g DHA-ethyl ester/100 g diet plus 3 g palm oil/100 g diet (DHA-EE group) or a diet containing 5 g palm oil/100 g diet (control group) for different periods of time. Maze-learning ability was assessed at 1 and 2 wk and 1 and 3 mo after the start of the control and experimental diets. In each maze-learning test, the time required to reach the maze exit and the number of times that a mouse strayed into blind alleys in the maze were measured in three trials, one every 4 d. After the last learning test in each trial, all mice were killed and the fatty acid compositions of plasma and brain lipids were determined. There were no significant differences in the results of the maze-learning tests between mice fed the diets at 1 or 2 wk in any of the three trials. After 1 and 3 mo, the DHA-EE diet groups required less time (P < 0.05) to reach the maze exit and strayed into blind alleys fewer times (P< 0.05) than did the control diet groups during trial 3. Significantly greater DHA levels were observed in the plasma and brain total lipids of the mice fed the DHA-EE diet after 2 wk, compared with those fed the control diet (P < 0.05), which was compensated for by lower arachidonic acid [20:4 (n-6)] levels. There were no significant differences in brain DHA levels among mice fed the DHA-EE diet for 2 wk, 1 mo, or 3 mo. Improved maze-learning ability after DHA intake was evident at 1 mo after the start of feeding and were maintained up to 3 mo, whereas the increased DHA levels in brain were apparent after feeding for just 2 wk. These results suggest that it may take time after the incorporation of DHA into the brain for improvement in learning ability to occur.

Effect of dietary docosahexaenoic acid and phosphatidylcholine on maze behavior and fatty acid composition of plasma and brain lipids in mice.

We investigated the effects of dietary docosahexaenoic acid (DHA, 22:6 n-3) and phosphatidylcholine (PC) on maze behavior and brain fatty acids in mice. Male Crj:CD-1 mice (3 wk old) were fed a diet containing 2% DHA and 3% palm oil (DHA group); 5% PC (PC group); 1% DHA, 2.5% PC and 1.5% palm oil (DHA + PC group); 5% palm oil (Palm oil control group) or MF laboratory chow (MF control group) for 7 mo. After this time maze-learning ability was assessed. The time required to reach the maze exit and the number of times that a mouse strayed into blind alleys in the maze were measured three times every four days. After the last learning test, all mice were sacrificed and plasma and brain were analyzed for fatty acid composition. The DHA and PC groups required less time to reach the maze exit and strayed less into blind alleys than the control group in the third trial. The difference between the DHA or PC groups and control mice was statistically significant (p < 0.05). In the total lipids of plasma and brain of mice fed DHA, there was a significant increase in DHA levels and a concomitant decrease in arachidonic acid (AA, 20:4 n-6). Similar changes in fatty acid composition were observed in brain phosphatidylcholine and phosphatidylethanolamine for this group of mice. However, this pattern of changes in brain fatty acids was not evident in the PC group. Our data suggest that maze-learning ability in mice is enhanced by intakes of DHA and PC. However, the mechanisms by which the DHA and PC diets improved learning ability appear to be different. A synergistic effect of DHA and PC on learning ability is not apparent in the DHA + PC group.

Intakes of Dietary Docosahexaenoic Acid Ethyl Ester and Egg Phosphatidylcholine Improve Maze-Learning Ability in Young and Old Mice

The effect of dietary docosahexaenoic acid (DHA) [22:6 (n-3)] ethyl ester (EE) and egg-phosphatidylcholine (PC) on maze-learning ability in young and old mice was studied. Male Crj:CD-1 mice aged either 3 wk or 14 mo were fed a diet containing 2 g DHA-EE/100 g diet plus 3 g palm oil/100 g diet (DHA-EE Group), 5 g egg-PC/100 g diet (egg-PC Group), 1 g DHA-EE/100 g diet plus 2.5 g egg-PC/100 g diet plus 1.5 g palm oil/100 g diet (DHA-EE + egg-PC Group) or 5 g palm oil/100 g diet (Control Group) for 5 mo. Maze-learning ability was assessed 4 mo after the start of the experiment. The time required to reach the maze exit and the number of times that a mouse strayed into blind alleys in the maze were measured in three trials every 4 d. In trial 2 of young mice, performed on d 4 after the first trial, the DHA-EE group required less (P < 0.05) time to reach the maze exit and DHA-EE and egg-PC groups strayed (P < 0.05) into blind alleys fewer times than the control group. In trial 2 of old mice, the DHA-EE, egg-PC and DHA-EE + egg-PC groups needed less (P < 0.05) time to find the exit and spent a fewer (P < 0.05) number of times in blind alleys than did the control group. The DHA-EE, DHA-EE + egg-PC and egg-PC groups strayed into blind alleys fewer times than the control group in trial 3 of old mice (P < 0.05). Our results suggest that the intake of DHA-EE and the egg-PC diet effectively enhances maze-learning ability and brain functions in old mice.

Effect of the long-term feeding of dietary lipids on the learning ability, fatty acid composition of brain stem phospholipids and synaptic membrane fluidity in adult mice: a comparison of sardine oil diet with palm oil diet

The effect of 12 month feeding of 5% palm oil or sardine oil diet on the maze-learning ability, fatty acid composition of brain stem phospholipids and synaptic membrane fluidity in mice was studied. The time required to reach the maze exit and the number of times that a mouse strayed into blind alleys in the maze were measured three times every 4 days. The time and number of mice fed on the sardine oil diet were less than those of animals fed on the palm oil diet in the first and second trials. The results of fatty acid composition analysis of brain stem phosphatidylethanolamine showed that the percentage of docosahexaenoic acid (22:6, n-3; DHA) was higher, but the arachidonic acid (20:4, n-6; AA) and docosatetraenoic acid (22:4, n-6; DTA) were lower in the sardine oil diet fed-mice than in the palm oil diet fed-animals. Moreover, the microviscosity of the synaptic plasma membrane in the sardine oil diet group was lower than that in the palm oil diet group. These results suggest that the adult mice fed on the sardine oil diet for a long period maintain higher levels of docosahexaenoic acid in brain phospholipids, synaptic membrane fluidity and maze-learning ability than animals fed on the palm oil diet.

Behavior and maze learning ability of dairy calves as influenced by housing, sex and sire

Two-hundred-and-seventy-five calves were allowed to enter a maze to determine how genetic and environmental effects influenced their time, direction first turned upon entry (laterality), and activity in a maze. Calves were put into the maze five times on Days 1, 2 and 3 post-weaning. Diet did not affect time, distance traveled, or activity score in the maze of 53 calves. On Day 2, males were slower to find the food source than females. On Day 3, calves reared in polyvinyl domes initially turned right more often than explained by chance. Activity differed between calves from different sires, sexes, during certain trials, and when the location of the food source was changed. There was nearly a threefold difference between sire groups in time required to pass through the maze. Maze time was slowest on Day 1, fastest on Day 2, and intermediate on Day 3 (when the location of the food source was changed). Sire groups differed in activity scores on all 3 days. There were significant correlations between maze time and activity scores, between activity score and laterality and between time and laterality on some days.

Tolman and Tryon. Early research on the inheritance of the ability to learn.

Few psychologists today are aware of the seminal role played by learning theorist Edward C. Tolman in the early development of the field of behavior genetics. Tolman was the first to publish a study of selective breeding for maze-learning ability in rats. He continued to foster research in this field by supporting the work of his students, particularly Robert C. Tryon. Tryon carried out the first major long-term study of maze-bright and maze-dull rats. This article focuses on Tolman's early years at Berkeley and the events culminating in the inheritance project, as well as on the evolution of this research under Tryon's direction.

The effect of a change in dietary habit upon maze learning ability in rats

An experimental psychological study was undertaken to assess the effect of a change in dietary habit upon behavioural development, using as a laboratory animal male Wistar rats maintained on natural foods and a processed food. Forty male Wistar rats were weaned at 21 days of age and divided into two equal groups. Group 1 was fed natural food (pressed wheat, dried fish, peanuts, cabbage and soybeans) and group 2 was fed powdered food. At 68 days of age, the rats were tested in a T-maze. The results showed that Group 1 excelled with regard to T-maze learning.

Teratological, neurochemical, and postnatal neurobehavioral assessment of METASYSTOX-R, an organophosphate pesticide in the rat

The purpose of this study was to assess the embryotoxic, fetotoxic, and teratogenic potential of METASYSTOX-R (MSR) in the rat. Furthermore, the study was designed to determine if maternally toxic doses of MSR altered fetal brain acetylcholinesterase (AChE), compromised neonatal survival, growth, and development, or affected neurobehavioral development. Inseminated female rats (45/dose group) received single daily oral doses of 0, 0.5, 1.5, or 4.5 mg/kg of MSR from Days 6 to 15. Dose groups were subdivided into three termination phases: Phase I, 5 females terminated on Day 16 of gestation; Phase II, 28 females terminated on Day 20 of gestation; Phase III, 12 females terminated on Day 21 postpartum. MSR produced a dose-related reduction in maternal plasma (30–72%), red blood cell (18–56%), and brain (21–68%) cholinesterase (ChE) activity, when measured on Day 16 of gestation. The high dose of MSR significantly ( p ≦ 0.05) reduced food consumption, suppressed body weight gain, and produced tremors in 98% of the dams. MSR administered at maternally toxic doses as high as 4.5 mg/kg was devoid of embryotoxic, fetotoxic, and teratogenic effects. Fetal brain AChE was not substantially different from control for any dose level in Day 20 fetuses. Furthermore, neonatal survival, growth, and development were unaffected and an extensive neurobehavioral testing scheme demonstrated no alteration of sensory or reflex functions, maze learning ability, or open field activity for neonates.

Water-maze learning in the mouse correlates with variation in hippocampal morphology.

We studied mouse learning performance in a water-maze task in order to explore the relations between heritable structural variation in the hippocampus and spatial learning abilities. Based on previous findings we hypothesized a relation between spatial learning abilities and the size of the intra- and infrapyramidal mossy fiber (iip-MF) terminal field. Factor analysis revealed that learning in this water maze has two components: one related to apparatus-induced activity and one related to maze-learning ability. The size of the iip-MF terminal field covaried negatively with the activity-related component but positively with the spatial-learning component. These findings are in agreement with previous results obtained for shuttle-box learning.