Cognitive procedural learning among children and adolescents with or without spastic cerebral palsy: the differential effect of age.

INTRODUCTION: Children learn to engage their surroundings skillfully, adopting implicit knowledge of complex regularities and associations. Probabilistic classification learning (PCL) is a type of cognitive procedural learning in which different cues are probabilistically associated with specific outcomes. Little is known about the effects of developmental disorders on cognitive skill acquisition. METHODS: Twenty-four children and adolescents with cerebral palsy (CP) were compared to 24 typically developing (TD) youth in their ability to learn probabilistic associations. Performance was examined in relation to general cognitive abilities, level of motor impairment and age. RESULTS: Improvement in PCL was observed for all participants, with no relation to IQ. An age effect was found only among TD children. CONCLUSIONS: Learning curves of children with CP on a cognitive procedural learning task differ from those of TD peers and do not appear to be age sensitive.

Impaired memory and learning abilities in patients with systemic lupus erythematosus as measured by the Rey Auditory Verbal Learning Test.

OBJECTIVE: The purpose of this study was to assess and characterise verbal memory impairment in patients with systemic lupus erythematosus (SLE) by the Rey Auditory Verbal Learning Test (Rey AVLT). METHODS: 40 consecutive, unselected patients with SLE were evaluated with the Rey AVLT, a clinical and research tool for the study of multiple learning and memory measures. All patients were assessed for disease activity, damage, presence of antiphospholipid antibodies and depression. Findings were compared with those of 40 healthy controls matched for age, sex and education. RESULTS: The study group included 40 patients with SLE (37 females, 3 males), median age 33 years (range 20-59), median disease duration 8 years (range 0.3-32). The median disease activity measured by the SLE Disease Activity Index (SLEDAI) was 4 (range 0-16). Median damage measured by the SLICC/ACR (Systemic Lupus International Collaborating Clinics/American College of Rheumatology) damage index score was 0 (range 0-4). Depression was detected in 16/40 patients. Several aspects of the memory domain, as measured by the Rey AVLT, were impaired in the SLE group, using analysis of variance with repeated measures. The learning curve of patients with SLE was significantly less steep compared with that of controls, (p = 0.036), the rate of words omitted from trial to trial was higher in the SLE group (p = 0.034) and retrieval was less efficient in SLE compared with controls (p = 0.004). The significance of these findings was maintained after omitting patients with stroke or depression. CONCLUSION: Learning ability was impaired in patients with SLE with a poor and inefficient learning strategy, as reflected by an impaired learning curve, repeated omissions and impaired retrieval. This pattern of memory deficit resembles that seen in patients with frontal lobe damage and warrants further localising brain studies.

Declarative and nondeclarative sequence learning tasks: closed-head injured patients versus control participants.

Patients who sustained closed-head injury (CHI) have been shown to have impaired memory for temporal order when measured under intentional, but not incidental, retrieval conditions. A group of 26 patients who sustained CHI and a matched control group of 26 individuals were tested on a declarative sequence learning task--"Chain Making" (CM), and a nondeclarative sequence learning task--Tower of Hanoi puzzle (TOHP). The TOHP is a problem solving task that requires planning and a strategic approach. The latter are cognitive processes known to be impaired following frontal lobe damage, as has been frequently documented in CHI patients. The goal of the present study was to test whether CHI patients' nondeclarative learning as measured by the TOHP task is preserved, as seen in amnesic patients, or impaired, as would be predicted following frontal lobe damage. Half of the participants in each group underwent active training, and the other half went through passive training of the tasks. The results demonstrate that the control group outperformed the CHI group (in most measures) in both declarative and nondeclarative sequence learning tasks. The effect of type of training differed for the two tasks: while performance of the control group on the TOHP was better under passive training (CHI patients did not improve on either one of the training modes), performance on the CM task was better under active training for both groups. The results are discussed in light of the role of the frontal lobes in memory generally, and in sequence learning particularly.

Traumatic brain injury (TBI) 10-20 years later: a comprehensive outcome study of psychiatric symptomatology, cognitive abilities and psychosocial functioning.

The goal of this study was to measure the very long-term mental and psychosocial outcomes of severe traumatic brain injury (TBI). Seventy-six persons with severe TBI were evaluated extensively by means of standardized scales, neuropsychological tests and evaluations by family members, at an average of 14.1 (SD = 5.5) years post-injury. Six mental and functional domains were examined: psychiatric symptomatology, cognitive abilities, vocational status, family integration, social functioning, and independence in daily routines. The findings indicate a long-term differential effect of severe TBI, with seriously affected psychiatric symptomatology, family and social domains, as compared to moderately influenced cognitive, vocational and independent functioning. Relatively high rates of depression, psychomotor slowness, loneliness and family members' sense of burden were found. In addition to their epidemiological importance, the results indicate that persons with TBI and their families may need professional assistance to maintain a reasonable psychosocial quality of life, even more than a decade post-injury.

The effect of electroconvulsive therapy (ECT) on implicit memory: skill learning and perceptual priming in patients with major depression.

While explicit memory in amnesics is impaired, their implicit memory remains preserved. Memory impairment is one of the side effects of electroconvulsive therapy (ECT). ECT patients are expected to show impairment on explicit but not implicit tasks. The present study examined 17 normal controls and 17 patients with severe major depressive disorder who underwent right unilateral ECT. Patients were tested in three sessions: 24-48 hours prior to, 24-48 hours following the first ECT, and 24-48 hours following the eighth ECT. The controls were tested in three sessions, at time intervals that paralleled those of the patients. Implicit memory was tested by the perceptual priming task - Partial Picture-Identification (PPI). The skill learning task used entailed solving the Tower of Hanoi puzzle (TOHP). Explicit memory was tested by picture recall from the PPI task, verbal recall of information regarding the TOHP, and by the Visual Paired Association (VPA) test. Results showed that explicit questions about the implicit tasks were impaired following ECT treatment. Patients' learning ability, as measured by the VPA task, was only impaired in the first testing session, prior to ECT treatment, reflecting the effect of depression. In addition, groups only differed in the first session on the learning rate of the skill learning task. Perceptual priming was preserved in the patients' group in all sessions, indicating that it is resilient to the effect of depression and ECT. The results are interpreted in terms of the differential effect of depression and ECT on explicit and implicit memory.

Criterion validation of premorbid intelligence estimation in persons with traumatic brain injury: "hold/don't hold" versus "best performance" procedures.

The goal of the present study was to validate previously suggested regression equations for the estimation of premorbid ability against a real premorbid intellectual criterion. Fifty-four patients with traumatic brain injuries, for whom a premorbid military Primary Psychometric Rating (PPR) was available, participated in the study. Two prediction procedures were validated: (a) "BEST-10", which generates a predicted score from the highest observed score of 10 WAIS-R subtests, according to the "best performance" estimation principle. (b) "BEST-2", which generates the predicted score from the higher of two subtests considered a priori resistant to neurological damage according to the "hold/don't hold" principle. The two procedures showed similar correlation with the premorbid criterion. However, the BEST-10 method provided a more accurate estimation, generating a non-significant 2-point underestimation. The results support the application of previously proposed equations for estimating premorbid intelligence, and suggest that the use of the best performance principle is preferable as compared to the hold/don't hold principle.

Motor and non-motor sequence learning in patients with basal ganglia lesions: the case of serial reaction time (SRT).

In order to address the question of whether the basal ganglia are involved exclusively in regulation of motor sequence learning, or if they are involved in non-motor sequence learning as well, two versions of the serial reaction time (SRT) task were administered: First is the standard version of the SRT task in which the sequence is executed motorically, and the second is a non-motor version of the task which requires response only to a particular position of the sequence. Sixteen patients with damage restricted to the region of the basal ganglia and 16 matched control subjects participated in this study. In addition to the motor and non-motor SRT tasks, two declarative memory tests (Visual Paired Associates and Rey Auditory-Verbal Learning Test) were administered to the participants. Results indicate that the two groups did not differ either on learning rate of the two declarative tasks, or on the declarative component of the SRT tasks (i.e., 'generate'). However, the control group was significantly superior to the basal ganglia (BG) group in learning a specific sequence in the motor and non-motor SRT tasks. Results suggest that the basal ganglia are involved in the regulation of non- motor as well as motor sequence learning.

Direct and indirect memory measures of temporal order and spatial location: control versus closed-head injury participants.

OBJECTIVE: The goal of the study was to compare control participants and participants with closed-head injury (CHI) on direct and indirect memory measures of temporal order and spatial location. METHOD: Twenty-seven CHI patients and 27 control participants were tested on "item" (i.e., words) and "contextual" (temporal order and spatial location) information. Contextual information was tested directly and indirectly by means of a format in which lists of words were presented repeatedly eight times in fixed or varying order for the temporal task and in a fixed or varying spatial position for the spatial task. The number of words recalled as well as their temporal and spatial judgment were the direct measure of item and contextual memory, respectively. The effect of the consistency of order or location was the indirect measure of contextual memory. RESULTS: As expected, the CHI group was impaired on the direct measures of item memory. Also as expected, the groups did not differ in the indirect memory measures of contextual information. Contrary to predictions, however, the groups did not differ in the direct measure of contextual information. CONCLUSIONS: Item memory, when measured directly, is impaired in CHI patients. The finding that the groups did not differ on the direct measure of contextual information is possibly due to ceiling-level performance of the control group. Contextual information seems to be preserved in CHI patients when measured indirectly.

Declarative and procedural learning in Parkinson's disease patients having tremor or bradykinesia as the predominant symptom.

The distinction between procedural and declarative memory is widely accepted in the memory literature. Converging evidence makes a strong case that the medial aspects of the temporal lobes and the diencephalon subserve the declarative memory system. However, the neuroanatomy of procedural memory is much less clear. In animal studies, damage to the basal ganglia has been found to affect procedural memory, but studies of patients suffering from degenerative diseases of the basal ganglia (e.g., Parkinson's and Huntington's disease) are less conclusive. Two groups of Parkinson's disease subtypes, with tremor (PDt) and bradykinesia (PDb) as the predominant motor symptom, were compared to controls on declarative and procedural memory tasks. The two patient groups did not differ from each other on the declarative tasks. However, in the procedural learning tasks, the PDb but not the PDt group, was significantly impaired compared to the control group. The results are discussed in terms of the differential involvement of discrete neuroanatomic loops connecting the basal ganglia and the prefrontal cortex.

Medical, cognitive, emotional, and behavioral outcomes in school-age children conceived by in-vitro fertilization.

Assessed long-term effects of assisted reproduction technologies of in-vitro fertilization (IVF) and related techniques of embryo transfer (ET) on children's adjustment. 51 school-age Israeli children conceived by IVF/ET were compared with 51 control-matched children conceived spontaneously. The assessment included a comprehensive medical evaluation, a psychological examination, teachers' reports, parents' reports, and children's self-reports. As compared with controls, IVF/ET children did not reveal significant differences in physical and neurological status or on cognitive measures of IQ, visual-motor coordination, visual memory, and verbal comprehension. Nevertheless, the IVF/ET children were scored lower by teachers on measures of socioemotional adjustment in school and on self-report measures of anxiety, aggression, and depression. Among IVF/ET children, the tendency to be at a greater risk for emotional disturbances was exacerbated among boys and among children whose parents were older.

Interpretation of facial expressions of affect in children with learning disabilities with verbal or nonverbal deficits.

The ability to identify facial expressions of happiness, sadness, anger, surprise,fear, and disgust was studied in 48 nondisabled children and 76 children with learning disabilities aged 9 through 12. On the basis of their performance on the Rey Auditory-Verbal Learning Test and the Benton Visual Retention Test, the LD group was divided into three subgroups: those with verbal deficits (VD), nonverbal deficits (NVD), and both verbal and nonverbal (BD) deficits. The measure of ability to interpret facial expressions of affect was a shortened version of Ekman and Friesen's Pictures of Facial Affect. Overall, the nondisabled group had better interpretive ability than the three learning disabled groups and the VD group had better ability than the NVD and BD groups. Although the identification level of the nondisabled group differed from that of the VD group only for surprise, it was superior to that of the NVD and BD groups for four of the six emotions. Happiness was the easiest to identify, and the remaining emotions in ascending order of difficulty were anger, surprise, sadness, fear, and disgust. Older subjects did better than younger ones only for fear and disgust, and boys and girls did not differ in interpretive ability. These findings are discussed in terms of the need to take note of the heterogeneity of the learning disabled population and the particular vulnerability to social imperception of children with nonverbal deficits.

Part I: the effect of long-term exposure to organic solvents on memory: a cross sectional study.

This study focuses on a wide range of different aspects of memory functions trying to ascertain a possible profile of memory changes, which take place following long-term exposure to organic solvents. The research design was cross-sectional. Study population included 31 industrial painters who were exposed at work to organic solvents and 31 unexposed workers. Workers after long-term exposure to organic solvents showed significant decline in memory as indicated in all three standard memory tests (i.e. Wechsler Memory Scale - Revised, Benton Revised Visual Retention Test, and Rey Auditory Verbal Learning Test). The results of Rey Auditory Verbal Learning Test showed a negative correlation with exposure index indicating that the more intensive and longer the time of exposure was, the more impaired is the verbal memory. It was also found that the affect of age on memory was stronger among workers after long-term exposure to organic solvents compared to the unexposed workers.

The effect of right and left hemispheric lesions on effortful and automatic memory tasks.

The effect of lateralised cerebral damage on two memory tasks-free recall of words and memory of their temporal order-was investigated under intentional, incidental, and ''true incidental'' learning conditions. Ten Right Brain Damaged patients (RBD), 10 Left Brain Damaged patients (LBD), as well as 15 age-matched and 15 younger control individuals, participated in this study. It was hypothesised that effortful and automatic memory processes involve predominantly the left and right cerebral hemispheres, respectively. Automaticity was defined either by the learning conditions (i.e. incidental-automatic and intentional-effortful) or by the type of task (i.e. temporal-order-automatic and free-recall-effortful) regardless of the learning conditions. In the free recall task the RBD group outperformed the LBD group under all learning conditions. In the temporal order task, the RBD group performed worse than normal controls under all learning conditions while the LBD group performed more poorly than matched controls in the intentional and incidental but not in the ''true incidental'' learning condition. The results are discussed in terms of the relationship between effortful and automatic memory processes and cerebral lateralisation.

Procedural and declarative memory processes: individuals with and without mental retardation.

Learning and retention of procedural versus declarative memory tasks were examined with 26 young adults with mild mental retardation and 27 school children matched for MA. Results revealed a similar pattern of task performance. Performance of the young adults with mild mental retardation was inferior to that of the control subjects on both types of tasks. However, learning rate and retention over time were comparable, thereby maintaining the control group's consistent advantage throughout all repeated trials. These results are consistent with previous findings for individual's with mental retardation tested on memory and problem-solving tasks. Theoretical implications of this pattern of results for individuals with mild mental retardation were discussed.

Indirect influence of modality on direct memory for words and their modality: closed-head-injured and control participants.

Twenty closed-head-injured (CHI) patients and 28 control participants were tested on recall and recognition of words. In addition, memory for modality (i.e., visual vs. auditory) of word presentation was measured directly (i.e., recognition) and indirectly (i.e, by its influence on word and modality recognition). As predicted, the CHI patients were impaired relative to controls on all of the direct memory tasks; that is, word recall, word recognition, and modality judgment. However, the CHI and control groups did not differ significantly on the magnitude of the modality effect (i.e., facilitation due to correspondence of modality in learning and test). The findings are interpreted in the theoretical framework that distinguishes between item (i.e., words) and source (i.e., modality) memory and between direct and indirect measures of memory.

Baseline performance and learning rate of procedural and declarative memory tasks: younger versus older adults.

Twenty-five older and 25 younger adults were compared on declarative (i.e., Rey Auditory-Verbal Learning Test and Visual Pair Associations) and procedural (i.e., Tower of Hanoi puzzle and Porteus mazes) learning tasks. A dissociation between learning rate on declarative and procedural tasks was demonstrated for the elderly participants. The younger group showed a steeper learning rate than the older group on the declarative tasks. By contrast, the learning rate of both groups on the procedural tasks did not differ consistently, whether the measure was number of errors/moves or time elapsed (with one exception in which the older group showed a steeper learning rate than the younger group). The younger group's baseline performance was better than that of the older group on all tasks employed in this study. These results reinforce the importance of distinguishing between baseline performance and the rate of learning on procedural learning tasks.

The effect of level of processing on perceptual and conceptual priming: control versus closed-head-injured patients.

Twenty-four closed-head-injured (CHI) and 24 control participants studied two word lists under shallow (i.e., nonsemantic) and deep (i.e., semantic) encoding conditions. They were then tested on free recall, perceptual priming (i.e., perceptual partial word identification) and conceptual priming (i.e., category production) tasks. Previous findings have demonstrated that memory in CHI is characterized by inefficient conceptual processing of information. It was thus hypothesized that the CHI participants would perform more poorly than the control participants on the explicit and on the conceptual priming tasks. On these tasks the CHI group was expected to benefit to a lesser degree from prior deep encoding, as compared to controls. The groups were not expected to significantly differ from each other on the perceptual priming task. Prior deep encoding was not expected to improve the perceptual priming performance of either group. All findings were as predicted, with the exception that a significant effect was not found between groups for deep encoding in the conceptual priming task. The results are discussed (1) in terms of their theoretical contribution in further validating the dissociation between perceptual and conceptual priming; and (2) in terms of the contribution in differentiating between amnesic and CHI patients. Conceptual priming is preserved in amnesics but not in CHI patients.

Direct and indirect memory measures of temporal order: younger versus older adults.

The memory changes associated with age are attributed to the deterioration of the frontal lobes, as well as to the middle temporal structures. Therefore, in addition to a decline in memory for facts and events, as found impaired in amnesics, a memory decline associated with age is predicted for tasks typically found impaired in frontal lobe patients (i.e., temporal order judgment). There are conflicting findings concerning whether indirect measures of memory for facts and events are associated with age. However, there are no studies that address this issue with regard to temporal order judgment. Thirty younger and thirty older adults were tested on a list of words which was repeated five times in fixed or varying order. The number of words recalled, as well as their temporal judgments, were the direct measure of memory. The effect of consistency of order of presentation on the number of words recalled was the indirect measure of memory for temporal order. Results suggest that direct, but not the indirect measures of memory were related to age.

Effect of breakfast timing on the cognitive functions of elementary school students.

OBJECTIVE: To study the effect of breakfast timing on selected cognitive functions of elementary school students. DESIGN: A 2-week randomized control intervention trial. SETTING: Five elementary schools. SUBJECTS: The subjects comprised 569 children, 51% of them boys, aged 11 to 13 years; the children were in grades 5 through 6 (17 classes). The subjects lived in different areas and had different socioeconomic backgrounds. INTERVENTION: Each subject was tested twice, by 2 versions of the Rey Auditory-Verbal Learning Test, 2 alternative forms of the logical memory subtest of the revised Wechsler Memory Scale, and 2 versions of the Benton Visual Retention Test. On the first test, before any nutritional intervention, the subjects were asked to complete a questionnaire about their food intake on the day of testing. Two thirds of the subjects received 200 ml of 3%-fat milk and 30 g of sugared cornflakes for the next 14 days, and all the subjects were reexamined on the 15th day. MAIN OUTCOME MEASURE: Scoring on the different tests was compared with baseline scores. RESULTS: After 15 days, children who ate breakfast at school scored notably higher on most of the test modules than did children who ate breakfast at home and children who did not at breakfast. CONCLUSIONS: Our results indicate that routinely eating breakfast 2 hours prior to being tested does not improve cognitive functions in 11- to 13-year-old elementary school students, but food supplementation 30 minutes prior to taking a test notably improves scoring. We suggest further studies on the relationship between meal content, feeding time, and scholastic performance.