Phyletic differences in learning.

It was hypothesized for many years that "the laws of learning were the same everywhere in the animal series… . It is difficult for the nonspecialist to appreciate quite how restricted has been the range of animals studied in experiments on animal learning because the restriction is so marked." Selected animal research is reviewed and a table is presented indicating behavior of a variety of animals in 4 classes of problem, (spatial reversal, spatial probability, visual reversal and visual probability) which differentiate rat and fish. Animals specified in the table are monkey, rat, pigeon, turtle, decorticated rat, fish, cockroach, and earthworm. Behavior of each kind of animal is evaluated in terms of its similarity to the behavior of 1 or the other of these 2 reference animals (rat and fish). This serves "as a summary of results already obtained" and "as a guide to further research." Systematic parametric variation is still of significance in comparative research; but "the table will save us some parametric effort in certain regions." An expanded table of this sort "will provide some useful clues to the evolution of intelligence and its relation to the evolution of the brain." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age differences in verbal learning.

"An old and a young group of Ss, mean ages 78.1 and 26.8 years, were given 3 paired-associate learning tasks which differed in the degree to which prior experience might be expected to facilitate or block present learning. They consisted of: (a) Familiar word pairs, (b) nonsense equations, and (c) false equations. Both groups performed best on the word-associate task, but there was little difference between the learning of nonsense and false equations within either group. On all 3 procedures the old group was significantly poorer, but they were proportionately more deficient in the learning of materials in which the facilitative effects of prior experience are minimized, i.e., the 2 forms of equations. However, they had no greater difficulty with the interference than with the nonsense material." 16 references. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age differences in incidental learning.

Examined the effects of age and of incidental-learning tasks on recall of a categorized word list. Ss were 50 18-30 yr old college students and 50 55-65 yr old teachers. The control groups were instructed to remember the words; incidental-learning groups performed orienting tasks, but were not informed that they would have to recall the words. 2 orienting tasks required that Ss process the meaning of the words; the other 2 orienting tasks did not involve semantic processing. Analysis of the free-recall data indicates that the semantic processing tasks led to much greater recall and organization of recall than the nonsemantic orienting tasks. In recall, there was a significant interaction between age and orienting task, with old Ss only manifesting incidental learning that was inferior to young Ss, whose orienting task involved semantic processing. The findings indicate that the presence or absence of an age-related decrement in incidental learning is predictable from the depth of processing of the incidentally acquired material. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Strain distribution of mice in discriminated Y-maze avoidance learning: Genetic and procedural differences.

The current study was conducted to characterize discriminated avoidance learning in mice by using a Y-maze task. In Experiment 1, the task parameters were manipulated, including the amount of time spent in the start arm, the amount of time to make the avoidance response, and the intertrial interval (ITI) using C57?×?SJL F1 hybrid mice. Avoidance performance was significantly improved with longer times to avoid the shock and longer ITIs. In Experiment 2, mice from 4 inbred strains (BALB/cByJ, DBA/2J, C57BL/6J, and SJL/J), an F1 hybrid (C57?×?SJL), and 1 outbred strain (CD1) were tested with various ITIs. Strain differences were observed in avoidance learning, with BALB, DBA, C57?×?SJL and CD1 mice showing significantly better avoidance learning than C57 mice, which were better than SJL mice. These data demonstrate that Y-maze performance is significantly influenced by the genetic background of the mouse and the parameters of the task. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Individual differences in dyadic cooperative learning.

The impact of individual differences on the performance of 2 roles—learner and learning facilitator—was assessed during dyadic cooperative learning. Eighty university students, 40 men and 40 women, participated in same-sex groups of 4. Each student cooperatively learned a text passage with 1 partner and then learned a 2nd passage with another partner. In a later session, the students recalled the information contained within both text passages and completed several personality measures. A social relations analysis (D. A. Kenny & L. LaVoie, 1984) was used to partition the variability in recall for the passages into various sources. Variability in recall depended strongly on individual differences in learning ability and (to a lesser extent) on individual differences in the ability to facilitate others' learning. Differences in the ability to learn text passages were independent of individual differences in the ability to facilitate others' learning. Effective learners were high in verbal ability, whereas effective learning facilitators were low in public self-consciousness and in self-monitoring. The influence of cognitive and rapport factors on the performance of the learner role and the learning facilitator role is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sex differences in learning and memory in mice: Effects of sequence of testing and cholinergic blockade.

Sexual dimorphism in spatial and cued navigation using the Morris water maze was examined in C57BL/6 mice both with and without administration of scopolamine, a cholinergic blocker. In Exp 1, female and male mice learned to perform first a spatial, then a cued, navigation task. Both performed a spatial task similarly; males, however, performed a cued task better than females. In Exp 2, the sequence of navigation testing was reversed. Both performed similarly on a cued task; however, males performed a spatial task better than females. In both experiments, females were more sensitive than males to the effects of scopolamine. No significant confounding sex differences were found in either spontaneous activity or passive avoidance retention. These data indicate that sex differences in spatial and cued tasks are dependent on the sequence of task presentation and implicate a role for the cholinergic system in these differences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Developmental differences in implicit learning of spatial context.

The authors examined whether a form of implicit memory that has been unambiguously dissociated from conscious awareness--learning of spatial context on the contextual cuing task introduced by M. M. Chun and Y. Jiang (1998)--is mature in childhood as predicted by an evolutionary view of cognition. School-aged children did not show reliable learning relative to adults who performed the same version of the task or another version that slowed responses to match those of children. Thus, unreliable learning in childhood was mediated by immature implicit representations of spatial context rather than by slower baseline response speed. The present finding is inconsistent with the prediction of the evolutionary view of cognition but consistent with incomplete maturation of medial temporal lobes known to mediate contextual learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sex and race differences in learning disabilities classrooms.

Poor reading performance is the primary reason for assignment of learning-disabled (LD) students to special education classrooms. Such classrooms typically contain a majority of Whites and males. The present study investigated whether or not differences by sex or race occurred in placement, teacher contacts, assignment practices, and student learning behaviors in LD classrooms. 105 6–12 yr old LD students were administered a battery of tests that included the Level I Reading Subtest of the Wide Range Achievement Test and the Spache Diagnostic Reading Scales. Results reveal differences in placement, similarity of teacher treatment and student behavior, and similarity of the effects of such behaviors on test performance. (43 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Anticipation interval and age differences in verbal learning.

Age differences were demonstrated to be greater at the shorter anticipation interval than at the longer in 2 paired-associate studies. Earlier work had suggested that this age-pace interaction was not a true learning effect but a performance deficit due to the difficulty the older person has in responding rapidly. The 2nd study provided evidence that relatively few of the errors made by the old Ss at the fast pace could be attributed to insufficient time to emit a learned response. Even when Ss were permitted to take as much time as needed to respond, the age-pace interaction was found. Several possible explanations for such a learning deficit were noted. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Savings tests: Separating differences in rate of learning from differences in initial levels.

Three experiments used a Pavlovian magazine-approach procedure in rats to explore, in 3 theoretically interesting cases, the inferences made from savings tests. In each experiment, a compound test procedure allowed the separation of differences in rate of acquiring new associative learning from differences in initial level of associative strength. Experiment I found that the slower acquisition after prior nonreinforced exposure (latent inhibition) reflected differences in learning rate, not initial level. By contrast, Experiments 2 and 3 found that the higher performance observed to a previously trained and extinguished stimulus, and lower performance observed to a conditioned inhibitor, both arose primarily because of differences in initial associative value. These experiments illustrate the usefulness of a novel testing procedure in sharpening the conclusions from savings procedures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age differences in retention as a function of learning.

The hypothesis that observed age-related decrements in recall scores derive primarily from degree of acquisition rather than from retention deficits per se was investigated. 40 elderly and 30 young Ss learned 9 paired associates under equal learning opportunity, learning to criterion or overlearning conditions. Retention was measured at 20 min. and 1 wk. Elderly Ss learned less on equal exposure and required more trials to criterion, but once having learned the material retained it as well as young Ss. Trials beyond criterion did not enhance the retention scores of elderly Ss and may have introduced negative motivational factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Gender differences in the learning status of diabetic children.

Evaluated the learning status of 95 diabetic boys and girls and 97 matched controls using the Wechsler Adult Intelligence Scale—Revised (WAIS—R) IQ factors and school histories. Of interest was whether diabetic boys would evidence more learning difficulties. Results indicated that diabetic boys had significantly lower Freedom From Distractibility scores compared with the scores of diabetic girls and control Ss and lower Perceptual Organization scores compared with scores of control boys. Although group scores were still within the average range of functioning, a significantly high percentage of diabetic boys (40%) compared with diabetic girls (16%) had learning problems that warranted either special instructional services or grade retention. Diabetic children experienced more learning difficulties (24%) than controls (13%), supporting research findings that diabetes is associated with increased risk of learning problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age differences in mediation in children's motor paired-associate learning.

In a combined verbal and motor paired-associate task, 138 children in kindergarten and 2nd and 4th grade learned nonsense names and spatial responses for 3 random shapes. Earlier findings that older children tend to learn the verbal and motor responses in consistent pairs were explained theoretically in terms of the development of mediated associations. The present purpose was to study age trends in the mediational process. Evidence for mediation was obtained at all 3 age levels. An increase in mediational effects with age is interpreted as evidence of control deficiency, since production deficiency was precluded. Rehearsal deficit in younger children is discussed as a possible explanation for the observed age trends. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age differences in repeated learning tasks in schizophrenic subjects.

This experiment was designed to study age differences in the learning of paired associates in serial order and a card-sorting task over 9 different sessions. The Ss consisted of 2 groups, 15 younger-aged (20-29) and 15 middle-aged (40-56), male, hospitalized schizophrenics. The results indicated that the younger-aged-group's performance was superior on both tasks for the 1st session. Over the 9 learning sessions the middle-aged group showed significantly greater improvement on the paired-associate task, while the differences between the age groups in card-sorting speed remained fairly constant over the 9 sessions. It was concluded that the learning deficit in middle-aged and schizophrenic Ss is something that is not a fixed and immutable one for all tasks but may be modified through practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Individual skill differences and large-scale environmental learning.

Spatial skills are known to vary widely among normal individuals. This project was designed to address whether these individual differences are differentially related to large-scale environmental learning from route (ground-level) and survey (aerial) perspectives. Participants learned two virtual environments (route and survey) with limited exposure and tested on judgments about relative locations of objects. They also performed a series of spatial and nonspatial component skill tests. With limited learning, performance after route encoding was worse than performance after survey encoding. Furthermore, performance after route and survey encoding appeared to be preferentially linked to perspective and object-based transformations, respectively. Together, the results provide clues to how different skills might be engaged by different individuals for the same goal of learning a large-scale environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Shock-induced hyperalgesia: IV. Generality.

Brief-moderate shock (3, 0.75 s, 1.0 mA) has opposite effects on different measures of pain, inducing antinociception on the tail-flick test while lowering vocalization thresholds to shock and heat (hyperalgesia) and enhancing fear conditioned by a gridshock unconditioned stimulus (US). This study examined the generality of shock-induced hyperalgesia under a range of conditions and explored parallels to sensitized startle. Reduced vocalization thresholds to shock and antinociception emerged at a similar shock intensity. Severe shocks (3, 25 s, 1.0 mA or 3, 2 s, 3.0 mA) lowered vocalization threshold to shock but increased vocalization and motor thresholds to heat and undermined fear conditioned by a gridshock or a startling tone US. All shock schedules facilitated startle, but only brief-moderate shock inflated fear conditioning. The findings suggest that brief-moderate shock enhances the affective impact of aversive stimuli, whereas severe shocks attenuate pain. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Individual differences in learning: Visual versus auditory presentation.

Investigated the possible interaction of individual differences in learning with mode of presentation. Ss were college students; data analyses were replicated by conducting separate analyses for 2 groups of 77 and 83 Ss, respectively. Each S learned 4 test lists of 20 words each, 2 under auditory and 2 under visual presentation. The main analyses indicated that individual differences in learning were reliable and that individual differences were just as predictable across as within modalities. A complementary analysis showed that Ss could not be reliably classified in terms of auditory–visual preference scores. The findings give no support to the contention that Ss can be classified as auditory learners or visual learners. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age-related differences in an ecologically based study of route learning.

Spatial learning abilities in younger adults and in healthy elderly adults were examined in 2 tasks. In the first task, participants were tested for their ability to recall relevant route information as well as to recognize and to order temporally landmark information observed along the route. Older participants had relatively greater difficulty retracing the route and temporospatially ordering landmarks but were equally good at recognition of landmarks occurring on the route. In the second task, participants memorized a 2-dimensional representation of a route and subsequently navigated the route from memory. Older participants had greater difficulty memorizing the route and navigating it. Errors of omission, commission, wrong, and forced choice were analyzed. Group differences in the pattern of errors differed by task. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Developmental sex differences in verbal learning

OBJECTIVE: To examine the health insurance experience and out-of-pocket health care costs of families with a child with IDDM. RESEARCH DESIGN AND METHODS: A case-control study of 197 families with a child with IDDM and 142 control families with no diabetic children was conducted. IDDM-affected families were identified from the Allegheny County IDDM Registry. Brothers and sisters of the parents in the IDDM-affected families were asked to participate as control subjects. Health insurance coverage and the money that families spent on health care services and supplies not reimbursed by insurance (out-of-pocket costs) were assessed by questionnaire. RESULTS: No difference was found between the IDDM-affected and control families in the percentages with or without insurance. Families with low household incomes ($10,000-$19,999) were at the greatest risk for having no insurance. While coverage provided by private plans was similar between the IDDM-affected and control families, many families had no reimbursement for insulin (10%), syringes (10%), or blood testing strips (30%). Out-of-pocket expenses were 56% higher in the IDDM-affected families than in the control families. Seventeen percent of the IDDM-affected families had expenses over 10% of their household income. This particularly affected families with low household incomes. Pre-existing illness clauses and insurance denial affected only a small proportion of the case families. CONCLUSIONS: These data illustrate that most families with a child with IDDM have health insurance, yet still incur larger out-of-pocket health care costs than do families without the presence of diabetes. IDDM-affected families likely face a number of economic decisions regarding health insurance and the use of health care.