Showing papers on "Verbal learning published in 2001"
TL;DR: This work focuses on recent successes in verbal learning, expert memory, language acquisition and learning multiple representations, to illustrate the implementation and use of chunking mechanisms within contemporary models of human learning.
826 citations
Journal Article•
TL;DR: Athletes with cerebral concussion demonstrated acute balance deficits, which are likely the result of not using information from the vestibular and visual systems effectively, and more research is necessary to determine the best neuropsychological test battery for assessing sport-related concussion.
Abstract: OBJECTIVE: Postural stability and neuropsychological testing are gradually becoming integral parts of postconcussion assessment in athletes. Clinicians, however, sometimes question the viability of instituting preseason baseline testing and the value of these results in making return-to-play decisions. Our purpose was to examine the course of recovery on various postural stability and neuropsychological measures after sport-related concussion. A secondary goal was to determine if loss of consciousness and amnesia, both of which are heavily weighted in most of the concussion classification systems, affect the rate of recovery. DESIGN AND SETTING: All subjects underwent a battery of baseline postural stability and neuropsychological tests before the start of their respective seasons. Any athletes subsequently injured were followed up at postinjury days 1, 3, and 5. Matched control subjects were assessed using the same test battery at the same time intervals. SUBJECTS: We studied 36 Division I collegiate athletes who sustained a concussion and 36 matched control subjects. MEASUREMENTS: We assessed postural stability using the Sensory Organization Test on the NeuroCom Smart Balance Master System and the Balance Error Scoring System. Neurocognitive functioning was measured with several neuropsychological tests: Trail-Making Test, Wechsler Digit Span Test, Stroop Color Word Test, and Hopkins Verbal Learning Test. RESULTS: Injured subjects demonstrated postural stability deficits, as measured on both the Sensory Organization Test and Balance Error Scoring System. These deficits were significantly worse than both preseason scores and matched control subjects' scores on postinjury day 1. Only the results on the Trail-Making Test B and Wechsler Digit Span Test Backward resulted in a logical recovery curve that could explain lowered neuropsychological performance due to concussive injury. Significant differences were revealed between the control and injured groups at day 1 postinjury, but a significant decline between baseline and postinjury scores was not demonstrated. Loss of consciousness and amnesia were not associated with increased deficits or slowed recovery on measures of postural stability or neurocognitive functioning. CONCLUSIONS: Athletes with cerebral concussion demonstrated acute balance deficits, which are likely the result of not using information from the vestibular and visual systems effectively. Neurocognitive deficits are more difficult to identify in the acute stages of concussion, although concentration, working memory, immediate memory recall, and rapid visual processing appear to be mildly affected. More research is necessary to determine the best neuropsychological test battery for assessing sport-related concussion.
746 citations
TL;DR: Some cognitive deficits appear detectable at least 7 days after heavy cannabis use but appear reversible and related to recent cannabis exposure rather than irreversible andrelated to cumulative lifetime use.
Abstract: Background: Although cannabis is the most widely used illicit drug in the United States, its long-term cognitive effects remain inadequately studied. Methods: We recruited individuals aged 30 to 55 years in 3 groups: (1) 63 current heavy users who had smoked cannabis at least 5000 times in their lives and who were smoking daily at study entry; (2) 45 former heavy users who had also smoked at least 5000 times but fewer than 12 times in the last 3 months; and (3) 72 control subjects who had smoked no more than 50 times in their lives. Subjects underwent a 28-day washout from cannabis use, monitored by observed urine samples. On days 0, 1, 7, and 28, we administered a neuropsychological test battery to assess general intellectual function, abstraction ability, sustained attention, verbal fluency, and ability to learn and recall new verbal and visuospatial information. Test results were analyzed by repeatedmeasures regression analysis, adjusting for potentially confounding variables. Results: At days 0, 1, and 7, current heavy users scored significantly below control subjects on recall of word lists, and this deficit was associated with users’ urinary 11nor-9-carboxy-9-tetrahydrocannabinol concentrations at study entry. By day 28, however, there were virtually no significant differences among the groups on any of the test results, and no significant associations between cumulative lifetime cannabis use and test scores. Conclusion: Some cognitive deficits appear detectable at least 7 days after heavy cannabis use but appear reversible and related to recent cannabis exposure rather than irreversible and related to cumulative lifetime use. Arch Gen Psychiatry. 2001;58:909-915
646 citations
TL;DR: Group differences in CPT Inattention, temporal discounting, and time reproduction were not a function of level of comorbid oppositional defiant disorder, delinquency, or anxiety–depression and are reasonably consistent with past research on EF and sense of time in children with ADHD.
Abstract: Clinic-referred teens (ages 12–19) with ADHD and ODD (N = 101) were compared to community control (CC) teens, equated for age and sex, (N = 39) on a variety of psychological tasks assessing executive functioning (EF), temporal reward discounting, and time estimation and reproduction. A factor analysis reduced the EF measures to three dimensions, representing CPT Inattention, Working Memory, and CPT Inhibition. Results indicated that the ADHD group had significantly more CPT Inattention than the CC group. No differences were found for Working Memory or CPT Inhibition. The ADHD group displayed significantly greater temporal discounting of delayed hypothetical monetary rewards relative to immediate ones and manifested more impaired time reproduction, but not time estimation, than did the CC group. Main effects for level of IQ were found only on the Working Memory factor and largely did not interact with the group factor otherwise. The group differences in CPT Inattention, temporal discounting, and time reproduction were not a function of level of comorbid oppositional defiant disorder, delinquency, or anxiety–depression. Results are reasonably consistent with past research on EF and sense of time in children with ADHD and extend these findings to the adolescent age group. Problems with working memory and CPT inhibition found in prior studies of children with ADHD, however, were not evident here, perhaps owing to age-related improvements or insufficient task difficulty.
632 citations
TL;DR: The authors used the headturn preference procedure to investigate infants' integration of multiple cues, such as stress, phonotactic constraints, and the statistical structure of the input, and found that infants find speech cues produced by coarticulation useful in word segmentation.
570 citations
TL;DR: Results indicated that common sound sequences were learned more rapidly than rare sound sequences across form and referent learning, and phonotactic probability appeared to influence the formation of semantic representations and the association between semantic and lexical representations.
Abstract: Though the influences of syntactic and semantic regularity on novel word learning are well documented, considerably less is known about the influence of phono-logical regularities on lexical acquis...
454 citations
TL;DR: The findings suggest that the N1-P2 complex may have clinical applications as an objective physiologic correlate of speech-sound representation associated with speech- sound training.
Abstract: ObjectiveTo determine whether the N1-P2 complex reflects training-induced changes in neural activity associated with improved voice-onset-time (VOT) perception.DesignAuditory cortical evoked potentials N1 and P2 were obtained from 10 normal-hearing young adults in response to two synthetic speech va
430 citations
TL;DR: This study used the task-set switching procedure in which good performance was independent of rule learning, and in which working memory load was reduced by explicitly cueing the task switches, to provide strong evidence for a specific cognitive set shifting deficit in patients with mild Parkinson's disease.
Abstract: Previous research on cognitive set shifting in patients with Parkinson's disease has often been confounded by concept formation, rule learning, working memory and/or general slowing of cognitive processes. To circumvent this problem, the present study used the task-set switching procedure in which good performance was independent of rule learning, and in which working memory load was reduced by explicitly cueing the task switches. Our results provide strong evidence for a specific cognitive set shifting deficit in patients with mild Parkinson's disease in a non-learning context, which also cannot be explained by general slowing of cognitive processes. Moreover, the deficit was robust in a small sample of patients at the earliest stages of the disease. Finally, the impairment in task-set switching was only apparent when competing information was present, i.e. when the load on selection mechanisms was increased.
392 citations
TL;DR: Findings suggest that theory-of-mind developments impact word learning, and whether children consider speakers' knowledge states when establishing initial word-referent links is addressed.
Abstract: Two studies addressed whether children consider speakers’ knowledge states when establishing initial wordreferent links. In Study 1, forty-eight 3- and 4-year-olds were taught two novel words by a speaker who expressed either knowledge or ignorance about the words’ referents. Children showed better word learning when the speaker was knowledgeable. In Study 2, forty-eight 3- and 4-year-olds were taught two novel words by a speaker who expressed uncertainty about their referents. Whether the uncertainty truly reflected ignorance, however, differed across conditions. In one condition, the speaker said he made the object himself and thus, he was knowledgeable. In the other condition, the speaker stated that the object was made by a friend and thus, expressed ignorance about it. Four-year-olds learned better in the speaker-made than in the friend-made condition; 3-year-olds, however, showed relatively poor learning in both conditions. These findings suggest that theory-of-mind developments impact word learning.
389 citations
TL;DR: The relationship between frontal lobe maturation and delayed recall observed here may be reflective of the children's development towards the more adult-like frontal lobe function revealed in the functional imaging studies.
Abstract: Previous studies conducted by our group have provided evidence for age-related reductions in cortical thickness in dorsal frontal and parietal regions between childhood and adulthood, and gray matter volume increases of mesial temporal and anterior diencephalic structures. The purpose of this study was to describe neurobehavioral correlates of these brain maturational changes using morphometric analyses of brain magnetic resonance images (MRI) and two tests of cognitive abilities. Participants were 35 normal children roughly stratified by age (7 to 16 years) and sex (20 boys and 15 girls) and frontal and mesial temporal regions were anatomically defined in each subjects' MRI data. The California Verbal Learning Test-Children's Version and the Rey-Osterrieth Complex Figure test were used as measures of verbal and visuospatial memory and organizational abilities. Analyses designed to show regionally specific relationships between the brain and behavioral measures revealed interesting results. Specifically, frontal lobe gray matter thinning was more strongly predictive of delayed verbal memory functioning than was the mesial temporal lobe gray matter volume, and this relationship did not appear to be mediated by factors indexed in chronological age. Similar, but less regionally specific relationships were observed for measures of visuospatial memory abilities and frontal lobe maturation. Functional imaging studies in the literature consistently report activation in frontal regions in adults during retrieval tasks. The relationship between frontal lobe maturation and delayed recall observed here may be reflective of the children's development towards the more adult-like frontal lobe function revealed in the functional imaging studies.
377 citations
TL;DR: The results suggest that approach-withdrawal states can have selective influences on components of cognitive control, possibly on a hemispheric basis and support and extend several frameworks for conceptualizing emotion-cognition interactions.
Abstract: Emotional states might selectively modulate components of cognitive control. To test this hypothesis, the author randomly assigned 152 undergraduates (equal numbers of men and women) to watch short videos intended to induce emotional states (approach, neutral, or withdrawal). Each video was followed by a computerized 2-back working memory task (spatial or verbal, equated for difficulty and appearance). Spatial 2-back performance was enhanced by a withdrawal state and impaired by an approach state; the opposite pattern held for verbal performance. The double dissociation held more strongly for participants who made more errors than average across conditions. The results suggest that approach-withdrawal states can have selective influences on components of cognitive control, possibly on a hemispheric basis. They support and extend several frameworks for conceptualizing emotion-cognition interactions.
TL;DR: Euthymic BDI patients demonstrate reductions in specific cognitive domains even after prolonged asymptomatic phases, some of these deficits appear to be associated with a more severe course of illness and poorer social and occupational functioning.
Abstract: Recent reports have suggested the presence of persistent cognitive impairments in patients diagnosed with Bipolar Disorder even after prolonged euthymic phases. In this work, various domains of cognitive function were examined in asymptomatic patients diagnosed with Bipolar I Disorder (BDI) in comparison with healthy subjects. Fifteen otherwise healthy BDI patients with a prior history of psychosis during mania completed a neuropsychological testing battery after a prolonged asymptomatic remission. Their scores were compared to those of individually matched healthy subjects with unpaired two-tailed t-tests at P<0.01. Relationships between cognitive performance measures and clinical variables related to illness severity were also examined with Pearson correlations, P<0.05. We detected poorer performance on measures of verbal learning, executive functioning and motor coordination in BDI patients compared to control volunteers. Scores on tests of executive functioning were negatively correlated with the number of episodes of mania and depression. Social and occupational scores were also associated with a poorer performance on measures of verbal learning and executive function. Euthymic BDI patients, therefore, demonstrate reductions in specific cognitive domains even after prolonged asymptomatic phases. Some of these deficits appear to be associated with a more severe course of illness and poorer social and occupational functioning.
TL;DR: The convergence observed across the 3 measurement procedures shows that the 3 procedures tap similar underlying processes and that recollection and familiarity differ in terms of conscious awareness, intentional control, and the manner in which they contribute to the shape of response confidence ROCs.
Abstract: The contributions of recollection and familiarity to recognition memory performance were examined using the process dissociation, remember-know, and receiver operating characteristic (ROC) procedures. Under standard test conditions the 3 measurement procedures led to process estimates that were almost identical and to similar conclusions regarding the effects of different encoding manipulations. Dividing attention led to a large decrease in recollection and a smaller, sometimes nonsignificant, decrease in familiarity. Semantic compared with perceptual processing led to a large increase in recollection and a moderate increase in familiarity. Moreover, the results showed that familiarity was well described by classical signal-detection theory but that recollection reflected a threshold process. The convergence observed across the 3 measurement procedures shows that the 3 procedures tap similar underlying processes and that recollection and familiarity differ in terms of conscious awareness, intentional control, and the manner in which they contribute to the shape of response confidence ROCs.
TL;DR: This article introduced the bind cue decide model of episodic memory, a Bayesian context noise model, and demonstrate how it can account for data from the item noise and dual-processing approaches to recognition memory.
Abstract: Item noise models of recognition assert that interference at retrieval is generated by the words from the study list. Context noise models of recognition assert that interference at retrieval is generated by the contexts in which the test word has appeared. The authors introduce the bind cue decide model of episodic memory, a Bayesian context noise model, and demonstrate how it can account for data from the item noise and dual-processing approaches to recognition memory. From the item noise perspective, list strength and list length effects, the mirror effect for word frequency and concreteness, and the effects of the similarity of other words in a list are considered. From the dual-processing perspective, process dissociation data on the effects of length, temporal separation of lists, strength, and diagnosticity of context are examined. The authors conclude that the context noise approach to recognition is a viable alternative to existing approaches.
TL;DR: The authors compared measures of phonotactic probability and lexical influence, including a new model of lexical neighborhoods, in their ability to explain empirical wordlikeness, and found that the influence of a lexical neighbor is an inverted-Ushaped function of its token frequency.
TL;DR: The results provide further evidence for age effects and sex differences in the neuromodulatory influences of dopamine on behavior in humans.
Abstract: OBJECTIVE: There is growing interest in distinguishing the biological bases of sex differences in behavior from environmental influences. Sex hormone levels seem to be related to some cognitive abilities, particularly memory, and the dopaminergic system participates in the mediation of memory. The dopamine transporter is the primary indicator of dopaminergic tone. This study investigated the relationship between cognition and dopamine transporter availability in healthy men and women. METHOD: Dopamine transporter levels were measured with a technetium-99m radiolabeled analog of cocaine, TRODAT-1, in 66 healthy volunteers (30 men and 36 women). A neuropsychological battery designed to target functions associated with dopaminergic activity was administered during the uptake interval between the radiopharmaceutical injection and image acquisition. RESULTS: Women and younger participants had higher dopamine availability in the caudate nucleus, and these groups also performed better on verbal learning tasks. F...
TL;DR: It is hypothesized that an adaptive cerebral response during cognitive performance following TSD with the specific pattern of adaptation depending on the specific cognitive processes performed should be tested.
01 Jan 2001
TL;DR: In this paper, the authors describe the neuropsychological profile of severe acute mania by using a range of tasks selected primarily for the detection of localized neural disruption within the prefrontal cortex.
Abstract: Objective: Mania has received little attention from a contemporary neuropsychological perspective despite its clear resemblance to the disinhibition syndrome sometimes seen after frontal brain injury, particularly injury to the inferior aspect of the prefrontal cortex. The purpose of this investigation was to describe the neuropsychological profile of severe acute mania by using a range of tasks selected primarily for the detection of localized neural disruption within the prefrontal cortex. Method: Fifteen acutely manic inpatients were compared with 30 nonpsychiatric subjects on tasks from the Cambridge Automated Neuropsychological Test Battery (Tower of London, spatial working memory, intradimensional-extradimensional attentional shift, and rapid visual information processing tasks) and on the Iowa Gambling Task, Stroop Color and Word Test, a verbal fluency task, and the California Verbal Learning Test. Results: Discriminant function analysis identified deficits in sustained attention (on the rapid visual information processing task) and verbal learning (on the California Verbal Learning Test) as the best indicators of manic performance, rather than deficits on any of the tests of executive functioning. The model correctly classified 91% of subjects overall and 87% of manic subjects. Manic patients did not resemble patients with ventromedial prefrontal cortex damage in their performance on the Iowa Gambling Task. Conclusions: Acute mania is characterized by core deficits in verbal memory and sustained attention against a background of milder impairments in functions that are traditional measures of prefrontal cortex integrity (attentional set shifting, planning, working memory). The data do not implicate ventral prefrontal cortex disruption as a locus of pathology in acute mania. Verbal memory and sustained attention deficits may relate differentially to the state and trait characteristics of bipolar disorder.
TL;DR: Acute mania is characterized by core deficits in verbal memory and sustained attention against a background of milder impairments in functions that are traditional measures of prefrontal cortex integrity (attentional set shifting, planning, working memory).
Abstract: OBJECTIVE: Mania has received little attention from a contemporary neuropsychological perspective despite its clear resemblance to the disinhibition syndrome sometimes seen after frontal brain injury, particularly injury to the inferior aspect of the prefrontal cortex. The purpose of this investigation was to describe the neuropsychological profile of severe acute mania by using a range of tasks selected primarily for the detection of localized neural disruption within the prefrontal cortex. METHOD: Fifteen acutely manic inpatients were compared with 30 nonpsychiatric subjects on tasks from the Cambridge Automated Neuropsychological Test Battery (Tower of London, spatial working memory, intradimensional-extradimensional attentional shift, and rapid visual information processing tasks) and on the Iowa Gambling Task, Stroop Color and Word Test, a verbal fluency task, and the California Verbal Learning Test. RESULTS: Discriminant function analysis identified deficits in sustained attention (on the rapid visu...
TL;DR: The authors show that the amount ofCC displacement is correlated with impairment in verbal learning ability and that CC displacement is a better predictor of verbal learning than regional CC area and further emphasize the vulnerability of midline brain structures to prenatal alcohol exposure.
Abstract: Background: Abnormalities of the corpus callosum (CC) have been documented in fetal alcohol syndrome (FAS), ranging from subtle decrements in its size to partial and even complete agenesis. Prenatal exposure to alcohol is also known to result in neurocognitive deficits. Objective: To 1) investigate abnormalities in size, shape, and location of the CC within the brain in individuals with FAS and in those exposed to high amounts of alcohol prenatally but without FAS (PEA group); and 2) determine if there is a relationship between callosal dysmorphology and cognitive test performance. Methods: MRI and novel surface-based image analytic methods were used. Twenty alcohol-exposed subjects (8 to 22 years) along with 21 normal controls (8 to 25 years) were studied with high-resolution MRI and measures of verbal learning and visuospatial abilities. Results: In addition to callosal area reductions, most severe in the splenium, the CC is significantly displaced in patients exposed to alcohol prenatally. In the alcohol-exposed group, this structure lies more anterior and inferior in posterior regions with relatively normal localization of anterior regions. These findings are significant in the FAS group, and a similar but less severe pattern is observed in the PEA patients. The authors show that the amount of CC displacement is correlated with impairment in verbal learning ability and that CC displacement is a better predictor of verbal learning than regional CC area. The brain–behavior relationship is only significant within the alcohol-exposed group, and the effect is not solely mediated by overall impaired verbal intellectual functioning. Conclusions: These results further emphasize the vulnerability of midline brain structures to prenatal alcohol exposure.
TL;DR: This is the first study to examine divided attention performance after TSD with neuroimaging and supports the previous suggestion that the brain may be more plastic during cognitive performance following TSD than previously thought.
Abstract: We recently reported that the brain showed greater responsiveness to some cognitive demands following total sleep deprivation (TSD). Specifically, verbal learning led to increased cerebral activation following TSD while arithmetic resulted in decreased activation. Here we report data from a divided attention task that combined verbal learning and arithmetic. Thirteen normal control subjects performed the task while undergoing functional magnetic resonance imaging (FMRI) scans after a normal night of sleep and following 35 h TSD. Behaviourally, subjects showed only modest impairments following TSD. With respect to cerebral activation, the results showed (a) increased activation in the prefrontal cortex and parietal lobes, particularly in the right hemisphere, following TSD, (b) activation in left inferior frontal gyrus correlated with increased subjective sleepiness after TSD, and (c) activation in bilateral parietal lobes correlated with the extent of intact memory performance after TSD. Many of the brain regions showing a greater response after TSD compared with normal sleep are thought to be involved in control of attention. These data imply that the divided attention task required more attentional resources (specifically, performance monitoring and sustained attention) following TSD than after normal sleep. Other neuroimaging results may relate to the verbal learning and/or arithmetic demands of the task. This is the first study to examine divided attention performance after TSD with neuroimaging and supports our previous suggestion that the brain may be more plastic during cognitive performance following TSD than previously thought.
TL;DR: This article investigated the role played by statistical learning in the acquisition of phrase structure and found that humans possess statistical learning mechanisms which may assist in the extraction of this abstract component of natural language.
TL;DR: The relationship between verbal and visual-spatial working memory and mathematical computation skill was examined in children and adults with and without disabilities in mathematics and it was concluded that, regardless of age, deficits in mathematics are mediated by both a domain-general and adomain-specific working memory system.
Abstract: The relationship between verbal and visual-spatial working memory and mathematical computation skill was examined in children and adults with and without disabilities in mathematics. A hierarchical regression analysis showed that, when partialing for the influence of reading ability, age, and gender, mathematical computation was better predicted by verbal than by visual-spatial working memory. Furthermore, the results showed that the relationship between mathematics ability and working memory were not significantly moderated by age but were stable across a broad age span. We concluded that, regardless of age, deficits in mathematics are mediated by both a domain-general and a domain-specific working memory system.
TL;DR: This finding highlights the importance of subjective memory complaints, which are important even at an early stage when objective tests are still unable to detect cognitive deficits and are especially important for elderly carriers of the APOE-ε4 allele because they have an additional risk.
Abstract: Objective: To investigate to what extent subjective memory complaints and APOE -e4 allele carriage predict future cognitive decline in cognitively intact elderly persons, by evaluating both their separate and combined effects. Methods: We selected 1,168 subjects from the population-based Longitudinal Aging Study Amsterdam who were 62 to 85 years of age and had no obvious cognitive impairment at baseline (Mini-Mental State Examination [MMSE] score, ≥27). Memory complaints and APOE phenotypes were assessed at baseline. MMSE, the Auditory Verbal Learning Test (memory: immediate recall and delayed recall), and the Alphabet Coding Task–15 (information processing speed) were used to study cognitive decline. Follow-up data were collected after 3 and 6 years. Data were analyzed with generalized estimating equations, adjusted for age, sex, education, and depression. Results: Baseline memory complaints were reported by 25.5% of the cognitively intact elderly persons. Overall, 25.3% of the subjects were carriers of at least one APOE -e4 allele. Memory complaints were associated with a greater rate of decline in all cognitive measures, except immediate recall. In addition, APOE -e4 allele carriers had a greater rate of cognitive decline shown by MMSE scores and slower information processing speeds after 6 years. The effects of both memory complaints and APOE -e4 allele carriage were additive: subjects with both factors had a two times higher cognitive decline than did subjects without both factors. Conclusions: Both memory complaints and APOE -e4 allele carriage predict cognitive decline at an early stage. This finding highlights the importance of subjective memory complaints, which are important even at an early stage when objective tests are still unable to detect cognitive deficits and are especially important for elderly carriers of the APOE -e4 allele because they have an additional risk.
TL;DR: A review and critique of the literature pertaining to the use of cognitive remediation techniques in patients with schizophrenia is presented, with mixed evidence suggesting that practice-based attention drills can improve performance on measures of sustained attention in schizophrenia.
Abstract: A review and critique of the literature pertaining to the use of cognitive remediation techniques in patients with schizophrenia is presented. The review is organized into three sections, according to the neuropsychological deficit targeted for remediation: 1) executive-function, 2) attention, and 3) memory. With regards to executive-function, despite an initial report suggesting that Wisconsin Card Sorting Test performance cannot be remediated, subsequent studies suggest that performance can be improved on a variety of dependent measures including perseverative errors, categories achieved, and conceptual level responses. These observations were confirmed by a meta-analytic investigation that revealed large mean effects sizes (d+ = 0.96) for these studies. Effect sizes were homogenous across discrepant remediation strategies and dependent measures. With regards to attention, serial scanning can be improved with instruction and reinforcement, whereas there is mixed evidence suggesting that practice-based attention drills can improve performance on measures of sustained attention in schizophrenia. With regards to memory, relatively simple semantic and affective elaborate encoding strategies elevates verbal list-learning memory in patients with schizophrenia to levels consistent with controls. A similar encoding procedure, combined with vigilance training, produces substantial improvement in social cue recognition. Avenues for future research are discussed.
TL;DR: Number of specific consonants produced consistently across the months of observation predicted referential lexical use at 16 months, whereas the transition to reference itself signaled the onset of a sharp increase in numbers of different words produced in a session.
Abstract: Researchers frequently examine the development of the single-word lexicon in the absence of phonetic data. Yet a large body of literature demonstrates relationships between the phonetics of babble and early speech, and it is clear that production skill is essential for establishing a lexicon. This study uses longitudinal productivity criteria to establish children's phonetic skill. Twenty children were followed from age 9 to 16 months, and their level of consistency of vocal patterns was examined in relation to their lexical production, providing a relatively large-sample demonstration of phonetic/lexical relationships at the transition to language. Number of specific consonants produced consistently across the months of observation predicted referential lexical use at 16 months, whereas the transition to reference itself signaled the onset of a sharp increase in numbers of different words produced in a session. The earliest referential speakers exhibited prior consistency in the production of [p/b], which also predominated in their words. Prior use of at least two supraglottal consonants characterized the referential group. Children varied in the specific consonants they produced consistently, and these same consonants, varying according to individual child repertoire, characterized nearly all consonant-based words produced by each child in both of the final 2 months of observation. These findings are interpreted in relation to the children's contemporaneous development of representational ability and pragmatic skill.
TL;DR: In this article, a prospective study of patients with 22q11.2 deletion syndrome (velocardiofacial/DiGeorge syndrome) is conducted, which is associated with a high frequency of learning disabilities.
Abstract: The 22q11.2 deletion syndrome (velocardiofacial/DiGeorge syndrome) is associated with a high frequency of learning disabilities. Although previous work has demonstrated that verbal skills are typically better preserved than non-verbal skills on both IQ and academic achievement testing in children with this syndrome, such measures are not sufficiently specific to determine a selective cognitive deficit. As part of an ongoing prospective study of patients with this syndrome, 29 children aged 5-17 with confirmed 22q11.2 deletions were assessed with a comprehensive neuropsychological test battery, including matched tasks of verbal and visuospatial memory. Results indicate that 22q patients displayed a selective deficit in visual-spatial memory, which was mirrored by deficits in arithmetic and general visual-spatial cognition. Further, a dissociation between visual-spatial and object memory was observed, indicating further selectivity of this pattern of deficit, and providing evidence for the dissociability of these components of visual cognition. These results indicate that children with 22q11.2 deletions display a specific neurocognitive phenotype, and suggest that this region of Chromosome 22q11 may harbor a gene or genes relevant to the etiology of nonverbal learning deficits.
TL;DR: In this paper, the authors present a multimodal approach to learning in the science classroom, which suggests that learning is realized through the interaction between visual, actional and linguistic communication (i.e. learning is multimodAL) and involves the transformation of information across different communicative systems ('modes'), e.g. from speech to image.
Abstract: This paper draws on ideas and data from the ESRC funded research 'Rhetorics of the science classroom: a multimodal approach'. It suggests that learning is realised through the interaction between visual, actional and linguistic communication (i.e. learning is multimodal) and involves the transformation of information across different communicative systems ('modes'), e.g. from speech to image. It demonstrates that learning is a process of selection, adaptation and transformation motivated by the interests of pupils and the context of learning. Speciecally, it analyses the different ways four Year 7 science pupils transformed their teacher's descriptions of cells in their production of texts on onion cells (and the choices they engaged with in producing them), focusing in particular on their use of analogy.
TL;DR: This paper examines the evidence for sensorimotor coding in working memory, including evidence from neuropsychology and from sign language research, as well as from standard working memory paradigms, and concludes that only a sensorim motor model can accommodate the broad range of effects that characterize verbal working memory.
Abstract: The highly influential Baddeley and Hitch model of working memory (Baddeley & Hitch, 1974; see also Baddeley, 1986) posited analogical forms of representation that can be broadly characterized as sensorimotor, both for verbal and for visuospatial material. However, difficulties with the model of verbal working memory in particular have led investigators to develop alternative models that avoid appealing either to sensory coding or to motoric coding, or to both. This paper examines the evidence for sensorimotor coding in working memory, including evidence from neuropsychology and from sign language research, as well as from standard working memory paradigms, and concludes that only a sensorimotor model can accommodate the broad range of effects that characterize verbal working memory. In addition, several findings that have been considered to speak against sensorimotor involvement are reexamined and are argued to be in fact compatible with sensorimotor coding. These conclusions have broad implications, in that they support the emerging theoretical viewpoint of embodied cognition.
TL;DR: The results suggest that both the neocortex and hippocampus are affected in patients with Cushing’s disease, andVerbal learning and other verbal functions seem more vulnerable than nonverbal functions.
Abstract: Objective The objective of this study was to use Cushing's disease as a unique human model to elucidate the cognitive deficits resulting from exposure to chronic stress-level elevations of endogenous cortisol. Methods Forty-eight patients with a first episode of acute, untreated Cushing's disease and 38 healthy control subjects were studied. Results Scores for four of five verbal IQ subtests were significantly lower in patients with Cushing's disease; their scores were significantly lower for only one nonverbal performance IQ subtest (block design). Verbal, but not visual, learning and delayed recall at 30 minutes were significantly decreased among patients with Cushing's disease. Although verbal delayed recall was significantly lower in these patients, the retention index (percentage), which compares the amount of initially learned material to that recalled after the delay, was not significantly decreased. There was no significant association between depression scores and cognitive performance. A higher degree of cortisol elevation was associated with poorer performance on several subtests of learning, delayed recall, and visual-spatial ability. Conclusions Chronically elevated levels of glucocorticoids have deleterious effects on particular domains of cognition. Verbal learning and other verbal functions seem more vulnerable than nonverbal functions. The results suggest that both the neocortex and hippocampus are affected.