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PubMed2005

Do parents lead their children by the hand?

The types of gesture+speech combinations children produce during the early stages of language development change over time. This change, in turn, predicts the onset of two-word speech and thus might reflect a cognitive transition that the child is undergoing. An alternative, however, is that the change merely reflects changes in the types of gesture + speech combinations that their caregivers produce. To explore this possibility, we videotaped 40 American child-caregiver dyads in their homes for 90 minutes when the children were 1;2, 1;6, and 1;10. Each gesture was classified according to type (deictic, conventional, representational) and the relation it held to speech (reinforcing, disambiguating, supplementary). Children and their caregivers produced the same types of gestures and in approximately the same distribution. However, the children differed from their caregivers in the way they used gesture in relation to speech. Over time, children produced many more REINFORCING (bike+point at bike), DISAMBIGUATING (that one+ point at bike), and SUPPLEMENTARY combinations (ride+point at bike). In contrast, the frequency and distribution of caregivers' gesture+speech combinations remained constant over time. Thus, the changing relation between gesture and speech observed in the children cannot be traced back to the gestural input the children receive. Rather, it appears to reflect changes in the children's own skills, illustrating once again gesture's ability to shed light on developing cognitive and linguistic processes.

Age Factors↗

PubMed2005

Principles, processes, and puzzles of social cognition: an introduction for the special issue on social cognitive neuroscience.

This article introduces the special issue of NeuroImage focused on social cognitive neuroscience. Social psychology has a rich history of making sense of the often paradoxical aspects of social cognition and the social world. This article reviews the principles, processes, and puzzles of social cognition and behavior that have been examined by social psychologists for decades. Five principles of social cognition and behavior are reviewed including: (1) the power of the situation over behavior, (2) blindness for situational influences, (3) social perception and self-perception are constructive processes, (4) blindness for the constructed nature of social and self-perception, and (5) self-processes are social. Four processes of social cognition are reviewed including: (1) cognitive architecture; (2) automaticity and control; (3) motivated reasoning; and (4) accessibility, frames, and expectations. Finally, five areas of social cognition that contain enduring puzzles are described including (1) the self, (2) attitudes, (3) reflective social cognition, (4) automatic social cognition, and (5) social motives. In several of the areas of study reviewed, cognitive neuroscience is well positioned to make important contributions to these research traditions either by allowing for new tests of hypotheses or by allowing for unobtrusive measurement of social cognitive processes.

Attitude↗

PubMed2003

Quantum-like formalism for cognitive measurements.

We develop a quantum formalism (Hilbert space probabilistic calculus) for measurements performed over cognitive systems. In particular, this formalism is used for mathematical modelling of the functioning of consciousness as a self-measuring quantum-like system. By using this formalism, we could predict averages of cognitive observables. Reflecting the basic idea of neurophysiological and psychological studies on a hierarchic structure of cognitive processes, we use p-adic hierarchic trees as a mathematical model of a mental space. We also briefly discuss the general problem of the choice of an adequate mental geometry.

Cognition↗

PubMed2006

Effects of a 14-day healthy longevity lifestyle program on cognition and brain function.

OBJECTIVE: The objective of this study was to determine the effects of a 14-day healthy longevity lifestyle program on cognition and cerebral metabolism in people with mild age-related memory complaints. METHODS: Seventeen nondemented subjects, aged 35-69 years (mean: 53 years, standard deviation: 10) with mild self-reported memory complaints but normal baseline memory performance scores were randomly assigned to 1) the intervention group (N = 8): a program combining a brain healthy diet plan, relaxation exercises, cardiovascular conditioning, and mental exercise (brain teasers and verbal memory training techniques); or 2) the control group (N = 9): usual lifestyle routine. Pre- and postintervention measures included self-assessments of memory ability, objective tests of cognitive performance, and determinations of regional cerebral metabolism during mental rest with [fluorine-18]fluorodeoxyglucose (FDG) positron emission tomography (PET). RESULTS: Subjects in the intervention group objectively demonstrated greater word fluency. Concomitantly, their FDG-PET scans identified a 5% decrease in activity in the left dorsolateral prefrontal cortex. The control group showed no significant change in any of the measures. CONCLUSIONS: A short-term healthy lifestyle program combining mental and physical exercise, stress reduction, and healthy diet was associated with significant effects on cognitive function and brain metabolism. Reduced resting activity in left dorsolateral prefrontal cortex may reflect greater cognitive efficiency of a brain region involved in working memory.

Adult↗

PubMed2026

Impact of N-PEP-12 Supplementation on Attentional Performance and Mental Wellbeing in Healthy Adults with Subjective Cognitive Complaints: A Randomized, Placebo-Controlled Trial.

Background: Subjective cognitive complaints (SCCs) are common in middle-aged and older adults and may reflect early cognitive changes, alongside alterations in stress, mood, sleep, and quality of life. N-PEP-12 is a peptide-based nutritional supplement with potential neuroprotective effects, but evidence of its benefits in healthy adults with SCCs remains limited. Objective: To evaluate the effects of N-PEP-12 supplementation on attention, cognitive function, and mental wellbeing in healthy middle-aged and older adults with SCCs. Methods: In this prospective, randomized, double-blind, placebo-controlled trial, 276 participants aged 50-75 years with SCCs and no clinically significant cognitive impairment were randomized to placebo, N-PEP-12 45 mg, or N-PEP-12 90 mg. Assessments were performed at baseline and after 30, 90, and 180 days. Primary outcomes included Test of Attentional Performance measures. Secondary outcomes included WAIS-IV Digit Span Forward and Backward, perceived stress, mood, sleep quality, and EQ-5D-5L visual analog scale. Results: Across the three primary attention outcomes analyzed jointly in a multivariate repeated-measures model, there was a significant group-by-visit interaction (p = 0.003) and a significant effect of visit (p < 0.001), without a significant main effect of treatment arm (p = 0.133), indicating a time-dependent treatment effect. This result was obtained in a sensitivity analysis population in which missing values were imputed under assumptions least favorable to the active arms. In exploratory endpoint-specific comparisons at 90 days, both N-PEP-12 groups showed greater improvements than placebo in alertness, attention omissions and memory omissions, and Digit Span Forward and Backward scores also improved. In a subsequent uncontrolled extension phase, in which all participants received active treatment, participants initially assigned to placebo showed comparable improvements after switching to N-PEP-12 90 mg. These observations are exploratory. Adverse events were infrequent and similarly distributed across groups. Conclusions: N-PEP-12 supplementation was associated with improvements in attention, working memory, and mental wellbeing in healthy middle-aged and older adults with subjective cognitive complaints. These findings support further investigation of N-PEP-12 as a nutritional intervention for early subjective cognitive changes associated with aging.

Humans↗

PubMed2003

Profiles of neuropsychologic function in schizophrenia.

In this article, the author reviews basic neuropsychologic issues in the study of schizophrenia. The first issue is whether cognitive dysfunction reflects a degenerative process or is a core feature of the disorder. Evidence demonstrating that cognitive difficulties are present at illness onset and are not caused by medication, illness progression, or other nonspecific factors is reviewed. The second question is less easily answered and deals with whether cognitive difficulties represent generalized dysfunction or differential deficits in specific neurocognitive domains. One difficulty in answering this question is the heterogeneous nature of the disorder. Clinical and cognitive subtyping approaches to reducing heterogeneity are discussed, with the conclusion that cognitive approaches hold the most promise for understanding subtype differences in neurobiologic substrates. Finally, the relation of cognitive ability to functional outcome is described, and it is explained why there is a resurgent interest in remediation efforts. The article closes with suggestions for future directions.

Cognition Disorders↗

PubMed2005

Seizure focus affects regional language networks assessed by fMRI.

OBJECTIVE: To investigate the degree of language dominance in patients with left and right hemisphere seizure foci compared to normal volunteers using a fMRI reading comprehension task. METHODS: Fifty patients with complex partial epilepsy, aged 8 to 56 years and 33 normal volunteers, aged 7 to 34 had fMRI (1.5 T) and neuropsychological testing. Participants silently named an object described by a sentence compared to a visual control. Data were analyzed with region of interest (ROI) analysis based on t maps for inferior frontal gyrus (IFG), midfrontal gyrus (MFG), and Wernicke area (WA). Regional asymmetry indices (AIs) were calculated [(L - R)/(L + R)]; AI > 0.20 was deemed left dominant and AI < 0.20 as atypical language. RESULTS: Left hemisphere focus patients had a higher likelihood of atypical language than right hemisphere focus patients (21% vs 0%, chi2 < 0.002). Left hemisphere focus patients, excluding those with atypical language, had lower regional AI in IFG, MFG, and WA than controls. Right hemisphere focus patients were all left language dominant and had a lower AI than controls in WA and MFG, but not for IFG. AI in MFG and WA were similar between left hemisphere focus/left language patients and right hemisphere focus patients. Patients activated more voxels than healthy volunteers. Lower AIs were attributable to greater activation in right homologous regions. Less activation in the right-side WA correlated with better verbal memory performance in right focus/left hemisphere-dominant patients, whereas less strongly lateralized activation in IFG correlated better with Verbal IQ in left focus/left hemisphere-dominant patients. CONCLUSIONS: Patients had lower asymmetry indices than healthy controls, reflecting increased recruitment of homologous right hemisphere areas for language processing. Greater right hemisphere activation may reflect greater cognitive effort in patient populations, the effect of epilepsy, or its treatment. Regional activation patterns reflect adaptive efforts at recruiting more widespread language processing networks that are differentially affected based on hemisphere of seizure focus.

Adaptation, Physiological↗

PubMed1977

The cognitive style dimension of reflectivity-impulsivity in normal and emotionally disturbed adolescents.

Thirty-two emotionally disturbed and 23 normal adolescents were given two test of cognitive style developed by Kagan (Matching Familiar Figures and the Haptic-Visual Tests). The results were analyzed to evaluate two major hypotheses: (a) that emotionally disturbed adolescents perform differently on the tests than normal adolescents; and (b) that members of both groups reveal a high degree of stability among various subtest scores, both within the same test and across different tests. In testing the first hypothesis, the authors discovered minimal differences in mean scores for the different samples on each of the five subtests involved. However, a more complex analysis was carried out on the basis of the assumption that extreme scores on the various items were a more meaningful indicator of performance than simple means. This analysis yielded the conclusion that these emotionally disturbed adolescents were more impulsive (i.e., answered more quickly and made more errors) than their counterparts in public schools. An analysis of the intercorrelations between different tests and within tests in testing the second hypothesis revealed 19 out of 40 significant correlations, with an additional 14 out of the remaining 21 in the predicted direction. Finally, nine out of the 10 correlations combining the subgroups were statistically significant.

Adolescent↗

PubMed2006

Relationship of cognitive measures and gray and white matter in Alzheimer's disease.

OBJECTIVE: To examine the relationship between commonly used screening cognitive measures with gray and white matter integrity in patients with mild to moderate AD. BACKGROUND: New neuroimaging techniques, such as voxel-based morphometry (VBM), make it possible to study the relationship between structural brain integrity and cognitive functioning in AD. METHODS: Gray and white matter integrity was evaluated using VBM in fifteen patients with mild to moderate AD. ADAS-Cog and MMSE scores were also performed as part of the baseline assessment for a larger clinical trial in the AD patients. Correlations between cognitive measures and VBM were performed. RESULTS: Both the ADAS-Cog and the MMSE showed a similar relationship with gray matter degeneration, reflecting greater cognitive impairment with decreased gray matter in the left temporal lobe. However, the MMSE score was much more reflective of underlying white matter changes than ADAS-Cog scores, particularly in frontotemporal region. These findings suggest that the ADAS-Cog and MMSE reflect different aspects of the underlying brain changes observed in AD. The ADAS-Cog was more specific to gray matter integrity whereas the MMSE reflected a more global reduction in both gray and white matter. CONCLUSIONS: These results support using neuroimaging markers of neural integrity as an important consideration when evaluating treatment efficacy. Furthermore, whole-brain analyses such as VBM help to evaluate neural systems that are not necessarily targeted by the treatment.

Aged↗

PubMed2006

Changes in LORETA and conventional patterns of P600 after steroid treatment in multiple sclerosis patients.

OBJECTIVE: The P600 component of event-related potentials (ERPs) reflecting the 'rule-governed sequence of information processing', has been associated with multiple sclerosis (MS)-related cognition. The present study aimed at examining the effects of methylprednisolone treatment in MS patients on cognition as reflected by the low-resolution brain electromagnetic tomography (LORETA) of the P600 as well as its conventional constituents (amplitudes and latencies) recorded during a working memory (WM) test. METHOD: A paired LORETA comparison was performed in the P600 component of ERPs elicited during a (WM) test in 18 MS patients suffering from the relapsing-remitting form, before and after 1 week treatment with methylprednisolone. The P600 component was also evaluated in 16 healthy controls matched to the patients on age and educational level. RESULTS: When pre- and post-treatment recordings of LORETA were compared all patients as a group showed significantly different patterns of current density activation located at right frontal lobe. The treatment was accompanied by an increase of the amplitude of P600 at the right frontoparietal area. In the post-treatment phase the patients exhibited significant improvement of the memory performance as compared to themselves before treatment. As a result both the P600 amplitudes and memory performance at post-treatment were closer to those exhibited by normal controls. CONCLUSION: These findings support the notion that steroid treatment in relapsing-remitting MS patients, may exert a beneficial effect in 'rule-governed sequence of information processing'.

Acoustic Stimulation↗

PubMed1993

Haloperidol potentiation of latent inhibition in rats: evidence for a critical role at conditioning rather than pre-exposure.

Latent inhibition (LI) reflects a cognitive process whereby repeated pre-exposure of a to-be-conditioned stimulus impairs subsequent conditioning. Since it is believed to reflect the ability of an organism to screen out irrelevant stimuli, disrupted LI has been suggested as a model for a cognitive deficit in schizophrenia. Animal studies have previously shown that indirect dopamine (DA) agonists can disrupt LI, an effect which is reversed by neuroleptics. Conversely, neuroleptics given alone potentiate LI. In this study, using pre-exposure to a tone stimulus which is subsequently paired with mild footshock, we have demonstrated that haloperidol given before conditioning only is equally as effective as haloperidol given twice, before pre-exposure and conditioning, in potentiating LI after 10 pre-exposures. This supports our earlier results with nicotine, pointing to conditioning as the critical time for the action of dopaminergic manipulations on LI. The implications for the use of potentiated LI as a screening test for neuroleptic action are discussed.

Journal Article↗

PubMed1994

Ethological study of the effects of tetrahydroaminoacridine (THA) on social recognition in rats.

Two major difficulties confront ethopharmacological investigations on cognitive abilities such as social recognition in drug-treated animals involved in free social interactions. The first concerns the choice of the most relevant behaviours, those reflecting the cognitive abilities attributed to the animals and assessing the specificity of the drug activity, and those reflecting non-specific drug effects. The second refers to the experimenter's awareness that in contrast to physical objects, social stimuli respond to drug-treated subjects and that their own level of responsiveness may influence the changes of drug-treated subjects' social interest. In addition, their contribution may vary according to the different treatments the drug-treated subjects receive. In examining the effects of tetrahydroaminoacridine (THA) at doses of 0.3, 1 and 3 mg/kg on the ability of adult male rats to recognize previously encountered conspecifics, we attempted to take into consideration such difficulties. A detailed behavioural profile of drug-treated rats was reported to separate specific from non-specific effects of THA. In addition, rats were assigned an index of responsibility for contact which takes into account the interactive dimension of each dyad and allows relevant comparisons between different treatments. The doses of THA which were found to decrease the duration of exploration of a familiar juvenile were also found to decrease the number of contacts initiated by the drug-treated subjects. THA induced a relative increase in body care by comparison to saline treatment. However, it had no effect of locomotor activity and rearing of the subjects. These findings enable dissociation of the effects of THA on cognitive versus non-cognitive processes.

Aging↗

PubMed2002

Cognitive assessment of geriatric schizophrenic patients with severe impairment.

There is evidence that some elderly patients with chronic schizophrenia experience marked impairments in cognitive functioning. Assessment of these patients may be difficult with traditional neuropsychological measures. The purpose of the present study was to determine if cognitive functioning could be validly assessed with the Alzheimer's Disease Assessment Scale-Late Version Cognitive factor score (ADAS-L Cog) in patients whose scores on the Mini-Mental State Examination (MMSE) reflect profound cognitive impairment. Patients with MMSE scores from 0 to 10 were selected from a larger database. Neuropsychological instruments designed for the assessment of mild to moderate dementia were found to be inadequate in this profoundly impaired population, due to floor effects. In contrast, there was a significant relationship between ADAS-L scores and several criterion measures, including the MMSE (R=-.71, P<.001), the Social Adaptive Functions Evaluation (SAFE) social functions scale (R=.47, P<.001), and the negative symptom total score of the Positive and Negative Syndrome Scale (PANSS) (R=.412, P<.001). The MMSE was somewhat less strongly correlated with both social functions (R=-.401, P<.001) and the negative symptom total score of the PANSS (R=-.366, P<.001). These results suggest that cognition can be reliably and validly assessed with instruments such as the ADAS-L that are designed for the assessment of severely impaired patients.

Journal Article↗

PubMed2006

Progressive cognitive decline in a transgenic mouse model of Alzheimer's disease overexpressing mutant hAPPswe.

The possibility of detecting progressive changes in cognitive function reflecting the spatio-temporal pattern of beta-amyloid peptide (Abeta) deposition was investigated in Tg2576 mice overexpressing the human mutant amyloid precursor protein (hAPP). Here, we show that at 7 months of age, Tg2576 mice exhibited a selective deficit in hippocampus-based operations including a defective habituation of object exploration, a lack of reactivity to spatial novelty and a disruption of allothetic orientation in a cross-shaped maze. At 14 months of age, Tg2576 mice displayed a more extended pattern of behavioral abnormalities, because they failed to react to object novelty and exclusively relied on motor-based orientation in the cross-shaped maze. However, an impaired reactivity to spatial and object novelty possibly reflecting age-related attention deficits also emerged in aged wild-type mice. These findings further underline that early cognitive markers of AD can be detected in Tg2576 mice before Abeta deposition occurs and suggest that as in humans, cognitive deterioration progressively evolves from an initial hippocampal syndrome to global dementia because of the combined effect of the neuropathology and aging.

Aging↗

PubMed2000

[Salivary testosterone and cognitive ability in children].

There are suggestive data with indicate the link of testosterone levels with specific cognitive abilities in humans. As soon as during intrauterine development, testosterone is supposed to influence to organization of fetal specific brain structures. This influence is permanent and it is reflected in cognitive abilities during prepubetal period. In puberty, the testosterone level rapidly increases mainly in boys and it appears to influence the definitive development of cognitive functions. In this paper, results of the first four years of our logitudinal study are presented. Salivary testosterone levels in children were determined, and their effect on spatial ability was studied. Radioimmunoanalytical method of testosterone determination in saliva was developed, since saliva reflects free fraction of testosterone directly available for uptake by receptors in the central nervous system. The sampling of saliva is non-invasive and unstressful, which is important for relevant evaluation of cognitive performance. One hundred and forty-seven children (78 boys and 69 girls) at the ae of 8 to 12 were examined. The data received from intellectually gifted children attending the School for gifted children in Bratislava (100 measurements) were compared with the data received from age-matched children attending randomly chosen elementary schools (151 measurements). Lower salivary testosterone levels were found in intellectually gifted children of both sexes, and negative relationship between testosterone levels and cognitive abilities in preadolescent children was observed.

Child↗

PubMedDate not supplied

Reduction in dissociation due to aging and cognitive deficit.

Our objective was to investigate whether dissociative experiences occur less frequently in older psychiatric patients than in younger adult patients, and to examine the role of cognitive deficits in the frequency of dissociative events. Fifty-two outpatients 60 years and older were administered the Dissociative Experiences Scale (DES) and the Mini-Mental State Exam (MMSE). Their scores were compared with those of 50 outpatients 35 to 55 years old. Each group included patients sampled from the Mental Health Center (MHC) and University Medical Center clinics. Older patients showed significantly lower DES and MMSE median scores than younger patients. Cognitive deficit reflected by reduced MMSE scores also was associated with reduced DES scores for younger and older patients. Older patients with little or no cognitive deficit continued to show reduced DES scores. Decreases in dissociativity continue well beyond the fourth decade and do not rely on age-related cognitive deficit. Factors related to the aging process seem to mediate reductions in dissociativity independent of reductions mediated by cognitive deficit. The use of the DES for screening without adjusting for age and cognitive status is questioned.

Adult↗

PubMed1998

Sulcal variability in the Alzheimer's brain: correlations with cognition.

We mapped the three dimensional (3D) extents and variability of selected sulci in the Alzheimer's brain and explored the relationship between sulcal pattern and patient's cognitive performance. High-resolution MRIs of 10 patients with probable Alzheimer's disease (AD) were linearly transformed into a standard "normalized" 3D atlas (known as the Talairach coordinate system) and, on each relevant slice, contours of the left and right Sylvian fissure, anterior and posterior calcarine, callosal, parietooccipital, and cingulate sulci and the floor of the temporal horn of the lateral ventricle were traced. These landmarks were chosen because of their relative invariant location across individuals and because they demarcate functional boundaries relevant in AD. The sulcal contours were resolved into two-dimensional surfaces that cut through a brain volume. All 10 patients' sulcal surfaces were averaged to determine their mean spatial locations in the Talairach coordinate system. The 3D spatial extents of each patient's sulci were compared with their disease severity based on neuropsychological performance. The 3D sulcal variability, within the "normalized" atlas space, ranged from 4.0 mm for the left callosal sulcus to 9.1 mm for the left Sylvian fissure. Significant correlations were found among the spatial extents for the posterior floor of the right temporal horn of the lateral ventricle (r = -0.89, p < 0.001 for vertical extent) and right anterior calcarine sulcus (r = -0.75, p < 0.01 for anterior-posterior extent) with copying ability of the Rey-Osterrieth Complex Figure; the right anterior calcarine also had a significant relationship (r = -0.72, p = 0.02 for anterior-posterior extent) with performance on the Block Design subtest from the Wechsler Adult Intelligence Scale-Revised. Verbal fluency performance measured by the Controlled Oral Word Association Test was significantly related to the left cingulate (r = 0.91, p < 0.001 for anterior-posterior extent, and r = -0.82, p < 0.01 for vertical extent) and right cingulate (r = -0.72, p < or = 0.02 for vertical extent) sulci. This exploratory study is the first to evaluate the relationship between 3D sulcal variability and cognition; our preliminary findings suggest that the 3D pattern of sulci in the AD brain is related to the severity of the disease as reflected by cognitive performance. In the Talairach brain atlas, sulcal variability, within an AD population, approaches 1 cm. This large variability requires correction when functional imaging data are transformed into the Talairach atlas space to "normalize" individual morphologic differences.

Aged↗

PubMed2003

Extinction after partial reinforcement: predicted vs. judged persistence.

The partial reinforcement extinction effect (PREE) (i.e., increased persistence following partial reward) is one of the most important generalizations from experimental studies of learning. Many theories of PREE assume that it involves cognitive and emotional mechanisms, but investigations of PREE have focused almost exclusively on behavioral measures. Four experiments with human adults investigated whether PREE is also reflected in cognitive measures. Independent groups of subjects learned an instrumental response under CRF vs. PRF contingencies, and then predicted (Experiments 1, 2, and 3) and/or judged (Experiments 3 and 4) their own persistence under extinction conditions. Predictions of persistcnce were unrelated to prior continuous or partial reinforcement contingencies (Experiments 1, 2, and 3), but subsequent judgments of persistence behavior were accurate (Experiments 3 and 4). These results indicate that increased persistence due to occasional reward is not well represented cognitively prior to its behavioral manifestation, but it is well represented after that manifestation. Possible explanations and implications of this apparent behavior cognition dissociation are discussed.

Adult↗