Home About us Contact
|
Home About us Contact | ||
|
|
||
Memory Abilities (memory + ability)
Selected AbstractsTests of a Dynamic Systems Account of the A-not-B Error: The Influence of Prior Experience on the Spatial Memory Abilities of Two-Year-OldsCHILD DEVELOPMENT, Issue 5 2001John P. Spencer Recently, Smith, Thelen, and colleagues proposed a dynamic systems account of the Piagetian "A-not-B" error in which infants' errors result from general processes that make goal-directed actions to remembered locations. Based on this account, the A-not-B error should be a general phenomenon, observable in different tasks and at different points in development. Smith, Thelen, et al.'s proposal was tested using an A-not-B version of a sandbox task. During three training trials and three "A" trials, 2-year-olds watched as a toy was buried in a sandbox at Location A. Following a 10-s delay, children searched for the object. Across five experiments, children's (total N= 92) performance on the A trials was accurate. After the A trials, children watched as a toy was hidden at Location B, 8 to 10 inches from Location A. In all experiments, children's searches after a 10-s delay were significantly biased in the direction of Location A. Furthermore, this bias toward Location A decreased with repeated trials to Location B, as well as when children completed fewer trials to Location A. Together, these data suggest that A-not-B,type errors are pervasive across tasks and development. [source] Influences of postconceptional age and postnatal experience on the development of auditory recognition memory in the newborn infantDEVELOPMENTAL PSYCHOBIOLOGY, Issue 3 2002Raye-Ann deRegnier Abstract We evaluated the effects of postconceptional age and postnatal experience on the development of neonatal auditory recognition memory. Three groups were tested: a premature newborn group (tested at 35,38 weeks postconceptional age, ,1 week old), a full-term newborn group (tested at 39,42 weeks postconceptional age, ,1 week old), and a full-term experienced group (tested at 39,42 weeks postconceptional age, >1 week old; range 8,30 days). Event-related potentials were collected while infants listened to the maternal voice alternating with a stranger's voice. Postconceptional age was correlated with the development of recognition memory for the maternal voice while there were qualitative effects of postnatal experience on latency measurements. Maturity of auditory cortical responses was not correlated with recognition memory abilities. We conclude that maturation of the recognition memory pathways is primarily a function of postconceptional age with qualitative effects of postnatal experience. Maturation of the auditory recognition memory pathway is not contingent upon maturation of the "P2" peak thought to arise from primary auditory cortex. © 2002 Wiley Periodicals, Inc. Dev Psychobiol 41: 216,225, 2002. Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/dev.10070 [source] Developmental dyslexia and explicit long-term memoryDYSLEXIA, Issue 3 2010Deny Menghini Abstract The reduced verbal long-term memory capacities often reported in dyslexics are generally interpreted as a consequence of their deficit in phonological coding. The present study was aimed at evaluating whether the learning deficit exhibited by dyslexics was restricted only to the verbal component of the long-term memory abilities or also involved visual-object and visual-spatial domain. A further goal of the present study was to investigate the predictive value of non-verbal long-term memory abilities with respect to word and non-word reading in dyslexic children. In accordance with these aims, performances of 60 dyslexic children were compared with that of 65 age-matched normal readers on verbal, visual-spatial and visual-object task. Results documented a generalized impairment of episodic long-term memory capacities in dyslexic children and the results did not vary as a function of children's age. Furthermore, in addition to verbal measures, also individual differences in non-verbal long-term memory tasks turn out to be good predictors of reading difficulties in dyslexics. Our findings indicate that the long-term memory deficit in dyslexia is not limited to the dysfunction of phonological components but also involves visual-object and visual-spatial aspect, thus suggesting that dyslexia is associated to multiple cognitive deficits. Copyright © 2010 John Wiley & Sons, Ltd. [source] Changes in individual and group spatial and verbal learning characteristics after anterior temporal lobectomyEPILEPSIA, Issue 6 2009Mario F. Dulay Summary Purpose:, To evaluate the effects of anterior temporal lobectomy (ATL) on individual and group spatial and verbal learning and memory abilities as a function of side of surgery and seizure control outcome. Methods:, We evaluated pre- and postsurgical learning and memory abilities of 75 left-hemisphere language dominant individuals who underwent ATL (33 left, 42 right) using the 8-trial Nonverbal Selective Reminding test and the 12-trial Verbal Selective Reminding test. Results:, Reliable change index methods indicated that 40.5% of individuals who underwent right-ATL had a clinically significant decline in spatial memory, and 62.5% of individuals who underwent left-ATL had a significant reduction in verbal memory. Growth curve analyses indicated that both side of surgery and poor seizure outcome independently affected the learning slope in the best fitting models. Left-ATL reduced the slope, but did not affect the overall shape, of verbal learning across trials. On the other hand, poor seizure control outcome affected the slope of spatial learning regardless of the side of surgery. Discussion:, Results demonstrate both individual and group declines in spatial memory and learning after ATL. Results suggest that individuals who undergo right-ATL should be counseled regarding the likelihood of a decline in spatial memory and learning abilities after ATL. Results also suggest that individuals with poor seizure control after ATL should be referred for rehabilitation services given the significant declines in spatial and verbal memory that occurred in our sample regardless of side of surgery. [source] Memory, Emotional and Vocational Impairments before and after Anterior Temporal Lobectomy for Complex Partial SeizuresEPILEPSIA, Issue 11 2006Mario F. Dulay Summary:,Purpose: To assess the pre- and postsurgical frequency of memory, emotional, and vocational impairments in patients who underwent anterior temporal lobectomy (ATL), and to assess the relationship between emotional disturbance and memory abilities after ATL. Methods: Retrospective analysis of data was performed on 90 patients with medically intractable complex partial seizures who underwent ATL between 1981 and 2003. Patients were evaluated an average of 5 months before surgery and 11.3 months after surgery. Results: A moderate to high frequency of memory impairment (44.4%; verbal or nonverbal), emotional disturbance (38.9%) and unemployment (27.8%) existed in the same individuals both before and after surgery. There were small to moderate rates of new onset memory (18.9%), emotional (11.1%), and vocational (7.8%) difficulties after surgery often regardless of seizure control outcome. Patients who underwent left-ATL and had emotional disturbance after surgery had the lowest verbal memory test scores. Conclusions: Results highlight the importance of taking into account emotional status when assessing memory abilities after ATL. Results replicate the finding of moderate to high frequencies of memory impairment, emotional disturbance, and unemployment both before and after ATL. Results provide support for the rationale that cognitive, psychiatric and vocational interventions are indicated to mitigate the problems that exist before and persist after ATL. [source] Phonological memory as a predictor of language comprehension in Down syndrome: a five-year follow-up studyTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 2 2004Glynis Laws Background:, This study reports the language and memory progress over five years of 30 adolescents and young adults with Down syndrome, and investigates the relationship of earlier phonological memory abilities to later language development. Methods:, Tests of nonverbal ability, receptive vocabulary, grammar comprehension, digit span and nonword repetition were administered at two points in time. Results:, For the sample as a whole, there were significant gains in nonverbal ability, receptive vocabulary and grammar comprehension, but no increases in phonological memory measured by nonword repetition or digit span. However, there were considerable individual differences in progress which, in part, were related to chronological age. Phonological memory improved in many younger participants but there were signs of decline in some older ones. Partial correlations between earlier nonword repetition scores and later language scores, controlling for nonverbal ability and earlier language scores, indicated a significant role for phonological memory in the acquisition of vocabulary knowledge. There was similar evidence of a role for phonological memory in grammar comprehension, but only for younger participants. Earlier receptive vocabulary also predicted later nonword repetition scores, particularly for participants with higher levels of vocabulary knowledge. Conclusion:, Relationships among the processes involved in language and memory development in Down syndrome may be similar to those established for typical development. [source] Daily ingestion of green tea catechins from adulthood suppressed brain dysfunction in aged miceBIOFACTORS, Issue 4 2008Keiko Unno Abstract Oxidative damage is believed to be an important cause of senescence. We have previously found that green tea catechins (GT-catechin), potent antioxidants, decrease oxidative damage to DNA and suppress brain dysfunction in aged senescence-accelerated mice (SAMP10) when ingested from the age of 1 month to the age of 12 months. To clarify the effect of GT-catechin on suppression of brain senescence, we investigated the effect of starting period to ingest GT-catechin. Six- or 9-month-old SAMP10 mice were allowed free access to water containing 0.02% GT-catechin. SAMP10 mice exhibit senescence characteristics such as shortened life span, atrophied forebrain and lowered learning and memory abilities. Learning ability was significantly higher in mice that ingested GT-catechin from the age of 6 months to 12 months when compared with same-aged control mice drank water without GT-catechin. Starting GT-catechin intake from the age of 9 months tended to improve learning ability. The ages of 6 and 9 months are thought to be adult and middle ages, respectively in SAMP10 mice. This result suggested that GT-catechin was helpful in suppressing brain dysfunction with aging even when ingestion started at the adult age. [source] Anosognosia for memory impairment in Alzheimer's diseaseACTA NEUROPSYCHIATRICA, Issue 4 2010Georgina Stewart Stewart G, McGeown WJ, Shanks MF, Venneri A. Anosognosia for memory impairment in Alzheimer's disease. Objective: To investigate whether patients with Alzheimer's disease (AD) were able to alter their awareness of memory deficits after exposure to a memory task. Methods: Thirty normal older adults and 23 mild AD patients participated in the study. Anosognosia was assessed using discrepancies between self- and informant-evaluations of cognitive and functional performance. Participants estimated their performance on the Verbal Paired Associates task at different points in time (before, immediately after the task and after a 1-h delay). Results: AD patients were generally less able to judge their memory abilities than healthy older adults, and tended to overestimate their task performance beforehand. Their prediction accuracy increased immediately after the task, but after a 1-h delay, they again misjudged their abilities at pretesting accuracy levels. Self-carer discrepancy scores of awareness of deficits in memory and other areas correlated significantly with memory tests but not with other neuropsychological tasks in the assessment, and larger discrepancy scores were associated with poorer performance. Conclusion: AD patients can monitor their task performance online, but are unable to maintain awareness of their deficits over time. Loss of awareness of memory deficits (or of any other deficits) in early stage AD may indicate damage to a system which updates a personal knowledge base with recent information. Failure to retain this information impedes abstraction from episodic to semantic memory. [source] The Effect of Learning Experiences and Context on Infant Imitation and GeneralizationINFANCY, Issue 6 2008Emily J. H. Jones Over the first years of life, infants gradually develop the ability to retrieve their memories across cue and contextual changes. Whereas maturational factors drive some of these developments in memory ability, experiences occurring within the learning event may also impact infants' ability to retrieve memories in new situations. In 2 experiments we examined whether it was possible to facilitate 12-month-old infants' generalization of learning in the deferred imitation paradigm by varying experiences before or during the demonstration session, or during the retention interval. In Experiment 1, altering the length, timing, or variability of training had no impact on generalization; infants showed a low, but consistent level of memory retrieval. In Experiment 2, infants who experienced a unique context for encoding and retrieval exhibited generalization; infants who experienced the context prior to the demonstration session, or during the retention interval, did not. Specificity is a robust feature of infant memory and is not substantially altered by encoding experiences in an observational learning paradigm. Previous history with a learning environment can, however, impact the flexibility of memory retrieval. [source] Capacity of People with Intellectual Disabilities to Consent to Take Part in a Research StudyJOURNAL OF APPLIED RESEARCH IN INTELLECTUAL DISABILITIES, Issue 2 2007Linda Dye Background, Within the context of current legislation relating to mental capacity in adults, the capacity of people with intellectual disabilities to consent to take part in research studies and the impact of different forms of information provision was experimentally investigated. Materials and methods, A questionnaire measure of ability to consent to take part in this research study was administered individually to participants. A total of 102 participants with intellectual disabilities were recruited from three day services for adults with intellectual disabilities. Consent information appertaining to taking part in an actual research project was presented to participants and their capacity assessed using a questionnaire. Three experimental conditions were used: ,,Control (n = 34) , consent information was presented followed by the questionnaire. ,,Section (n = 34) , consent information was broken into sections and the appropriate questions were asked following each section. ,,Photograph (n = 34) , consent information was accompanied by six colour photographs, followed by the questionnaire. Participants also completed measures of memory ability, verbal ability and non-verbal problem-solving ability. Results, Seventeen participants withdrew from the study at some point. Of the remaining 85 participants, no significant differences in ability to consent scores were found between the experimental conditions. Using this measure, only five participants (5.9%) were deemed able to consent, i.e. scored the minimum required on each aspect of consent. Conclusions, The validity and usefulness of the current dichotomous concept of consent is challenged as only a small proportion of participants were deemed able to consent. [source] Purple Sweet Potato Color Alleviates D-galactose-induced Brain Aging in Old Mice by Promoting Survival of Neurons via PI3K Pathway and Inhibiting Cytochrome C-mediated ApoptosisBRAIN PATHOLOGY, Issue 3 2010Jun Lu Abstract Purple sweet potato color (PSPC), a class of naturally occurring anthocyanins, protects brain function against oxidative stress induced by D-galactose (D-gal) (Sigma-Aldrich, St. Louis, MO, USA). Our data showed that PSPC enhanced open-field activity, decreased step-through latency, and improved spatial learning and memory ability in D-gal-treated old mice by decreasing advanced glycation end-products' (AGEs) formation and the AGE receptor (RAGE) expression, and by elevating Cu,Zn-superoxide dismutase (Cu,Zn-SOD) (Sigma-Aldrich) and catalase (CAT) expression and activity. Cleavage of caspase-3 and increased terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP) nick-end-labeling (TUNEL)-positive cells in D-gal-treated old mice were inhibited by PSPC, which might be attributed to its antioxidant property. PSPC also suppressed the activation of c-Jun NH2 -terminal kinase (JNK) and the release of cytochrome c from mitochondria that counteracted the onset of neuronal apoptosis in D-gal-treated old mice. Furthermore, it was demonstrated that phosphoinositide 3-kinase (PI3K) activation was required for PSPC to promote the neuronal survival accompanied with phosphorylation and activation of Akt and p44/42 mitogen-activated protein kinase (MAPK) by using PI3K inhibitor LY294002 (Cell Signaling Technology, Inc., Beverly, MA, USA), implicating a neuronal survival mechanism. The present results suggest that neuronal survival promoted by PSPC may be a potentially effective method to enhance resistance of neurons to age-related disease. [source] | |||||||||||||