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A comparison of neurocognitive function in nonsmoking and chronically smoking short-term abstinent alcoholics.

Approximately 70-90% of individuals in North America seeking treatment for alcoholism are chronic smokers. A growing body of evidence suggests chronic cigarette smoking alone adversely affects neurocognition in adults. However, few studies on the neurocognitive function of short-term abstinent alcoholics have specifically considered the potential effects of chronic cigarette smoking. In this study, 20 nonsmoking recovering alcoholics (nsRA) and 22 actively smoking recovering alcoholics (sRA) participants, matched on age and education, were contrasted on a comprehensive neurocognitive battery after 34+/-9 days of abstinence. nsRA were superior to sRA on measures of auditory-verbal learning and memory, processing speed, cognitive efficiency, and static postural stability. These group differences were not a function of group disparities in age, education, estimated premorbid verbal intelligence, lifetime alcohol consumption, or other measured comorbid psychiatric or medical factors. In sRA, longer smoking duration was negatively correlated with executive skills, visuospatial learning, general cognitive efficiency, and static postural stability. These results indicate that greater consideration of the potential neurobiological effects of current chronic smoking on neurocognitive functioning is warranted in studies of alcoholism and other conditions where smoking is a common comorbid factor.

Adult↗

Impact of an educational program on the safety of high-risk, visually impaired, older drivers.

BACKGROUND: Older drivers (licensed drivers aged 60 years and older) have among the highest rates of motor vehicle collision involvement per mile driven of all age groups. Educational programs that promote safe driving strategies among seniors are a popular approach for addressing this problem, but their safety benefit has yet to be demonstrated. The objective of this study was to determine whether an individualized educational program that promoted strategies to enhance driver safety reduces the crash rate of high-risk older drivers. DESIGN/ SETTING: Randomized, controlled, single-masked intervention evaluation at an ophthalmology clinic. PARTICIPANTS: A total of 403 older drivers with visual acuity deficit or slowed visual processing speed or both who were crash-involved in the previous year, drove at least 5 days or 100 miles per week or both, and were at least 60 years old. INTERVENTION: Patients were randomly assigned to usual care (comprehensive eye examination) or usual care plus an individually tailored and administered educational intervention promoting safe-driving strategies. MAIN OUTCOME MEASURE: Police-reported vehicle collision rate, expressed both in terms of person-years of follow-up and person-miles of travel for 2 years postintervention. RESULTS: The intervention group did not differ significantly from the usual care only group in crash rate per 100 person-years of driving (relative risk [RR], 1.08; 95% confidence interval [CI], 0.71-1.64) and per 1 million person-miles of travel (RR, 1.40; 95% CI, 0.92-2.12). The intervention group reported more avoidance of challenging driving maneuvers and self-regulatory behaviors during follow-up than did the usual care only group (p<0.0001). CONCLUSIONS: An educational intervention that promoted safe-driving strategies among visually impaired, high-risk older drivers did not enhance driver safety, although it was associated with increased self-regulation and avoidance of challenging driving situations and decreased driving exposure by self-report.

Accident Prevention↗

Role of glucose in chewing gum-related facilitation of cognitive function.

This study tests the hypothesis that chewing gum leads to cognitive benefits through improved delivery of glucose to the brain, by comparing the cognitive performance effects of gum and glucose administered separately and together. Participants completed a battery of cognitive tests in a fully related 2 x 2 design, where one factor was Chewing Gum (gum vs. mint sweet) and the other factor was Glucose Co-administration (consuming a 25 g glucose drink vs. consuming water). For four tests (AVLT Immediate Recall, Digit Span, Spatial Span and Grammatical Transformation), beneficial effects of chewing and glucose were found, supporting the study hypothesis. However, on AVLT Delayed Recall, enhancement due to chewing gum was not paralleled by glucose enhancement, suggesting an alternative mechanism. The glucose delivery model is supported with respect to the cognitive domains: working memory, immediate episodic long-term memory and language-based attention and processing speed. However, some other mechanism is more likely to underlie the facilitatory effect of chewing gum on delayed episodic long-term memory.

Adolescent↗

Post-intervention effectiveness of a computerized personalized cognitive stimulation program adapted according to cognitive reserve in older adults without cognitive impairment in Primary Care: A randomized clinical trial.

BACKGROUND: Cognitive reserve may influence responsiveness to cognitive interventions, yet it is rarely used to tailor computerized stimulation. OBJECTIVE: To evaluate the effectiveness of a computerized cognitive stimulation program personalized according to cognitive reserve on cognition, reserve-related activities, and digital competence in community-dwelling older adults without cognitive impairment in Primary Care. METHODS: In this randomized clinical trial, 102 adults aged &#x2265;65 years with normal cognitive performance were recruited from three primary care centers in Zaragoza, Spain, and stratified by cognitive reserve level before random allocation to intervention or control. The intervention comprised digital literacy sessions followed by 8 weeks of home-based computerized cognitive stimulation tailored to participants' cognitive reserve profiles and life history. Controls received a single group-based health education session focused on maintaining everyday cognitive activity. Outcomes were assessed at baseline and post-intervention using global cognition (MEC-35), the Cognitive Reserve Questionnaire, the Mobile Device Proficiency Questionnaire-16, and domain-specific neuropsychological tests. A total of 100 participants completed the final evaluation and were included in complete-case analyses. RESULTS: Compared with controls, the intervention group showed greater adjusted post-intervention improvements in global cognition (MEC-35 between-group difference: 1.8 points) and several cognitive measures, including temporal orientation, calculation, attention, praxis, verbal fluency, processing speed, executive functions, and verbal learning. CRQ scores and digital competence also improved, with small-to-large effect sizes. CONCLUSIONS: A computerized cognitive stimulation program adapted according to cognitive reserve appears feasible in Primary Care and may improve cognition, engagement in reserve-related activities, and digital competence in older adults without cognitive impairment.

Humans↗

Rapid serial naming: relations between different stimuli and neuropsychological factors.

We report two studies on rapid serial naming (RSN). Study 1 addressed the relations among RSN tasks comprising different stimuli. Separate components for RSN of alphanumeric and non-alphanumeric stimuli, as well as for tasks in which the stimuli alternated between categories were identified. In Study 2, phonological skills, processing speed, motor dexterity, and verbal fluency were found to explain RSN performance. The studies indicate: (1) that RSN tasks vary in their properties according to the stimuli used and according to the way the tasks are arranged, and (2) that RSN tasks are multi-componented.

Child↗

Neuropsychological functioning in youth with bipolar disorder.

BACKGROUND: Little is known about the neuropsychological status of youth with bipolar disorder (BPD) or whether cognitive deficits in this population are accounted for by comorbidity with attention deficit/hyperactivity disorder (ADHD). We compared neuropsychological and academic functioning of youth with and without DSM-IV BPD, controlling for effects of comorbid ADHD. METHODS: Fifty-seven youth with BPD and 46 healthy control subjects were assessed on a battery of clinical neuropsychological measures including subtests from the Wechsler Intelligence Scales for Children and Adults (Third Editions), the Stroop, the Wisconsin Card Sorting Test, the Rey-Osterreith Complex Figure, an auditory working memory Continuous Performance Test, a measure of verbal learning, and the Wide Range Achievement Test-Third Edition. RESULTS: Bipolar disorder was associated with impairments on subtests reflecting sustained attention, working memory, and processing speed after controlling for ADHD. Additionally, decrements of moderate effect sizes were found for measures of interference control, abstract problem solving, and verbal learning but did not meet criteria for statistical significance. CONCLUSIONS: After controlling for ADHD, youth with BPD show neuropsychological deficits similar to impairments found in adults with the disorder. Further studies are needed to understand the clinical implications of these impairments as well as their role in the underlying risk for pediatric BPD.

Adolescent↗

Lateralization of cerebral hemodynamics during Wisconsin Card Sorting Test: a functional transcranial Doppler sonography study.

OBJECTIVE: Studies on lateralization of cerebral metabolism during Wisconsin Card Sorting Test (WCST), a well-known paradigm of category learning, have shown mixed results. Moreover, sorting dimension (number, color and shape) is a cofounder of laterality in WCST. Functional transcranial Doppler sonography (fTCD) has a high temporal resolution and allows the measurement of mean cerebral blood flow velocity (CBFV) in the middle (MCA) and anterior cerebral arteries (ACA), which supply lateral and medial parts of the frontal and parietal lobes, respectively. We used fTCD to investigate CBFV changes occurring in both MCA and ACA during WCST and different sorting dimensions. METHODS: Twenty-one subjects underwent twice two distinct phases of the WCST, namely maintaining a rule (maintaining set) and searching for a new rule (set shifting), during bilateral fTCD of the MCA and ACA. RESULTS: There was a left-sided dominance of CBFV during maintaining set and set shifting in the MCA. CBFV was not associated with test performance. The sorting dimension number caused the highest CBFV increase in both MCA and ACA during maintaining set, and the sorting dimension shape caused lowest CBFV decrease in both MCA during set shifting. CONCLUSIONS: This study confirms results that cerebral blood flow (CBF) lateralizes to the left side during WCST. The 3 sorting dimensions provoked distinct processing speed during maintaining set and set shifting, but caused no effect on hemispheric lateralization. SIGNIFICANCE: Functional transcranial Doppler sonography can be used to assess CBFV during WCST and different sorting dimensions, and the latter modulate reaction time and cerebral hemodynamics.

Adult↗

Four-month-old infants process own mother's voice faster than unfamiliar voices--electrical signs of sensitization in infant brain.

Four-month-old infants heard their own mother's voice and a voice of an unfamiliar female as "oddballs" in a stream of acoustic information. The neuronal processing from 50 to 500 ms (as evaluated with event-related brain potentials, ERPs) was expected to be obligatory and from 500 to 900 ms to include cognitive processing. There was a clear shift in the processing speed between the mother's and unfamiliar voices at around 350 ms. While earlier obligatory ERP components occurred at significantly shorter latency to the mother's voice, later endogenous components were significantly delayed relative to the unfamiliar voice. The amplitude differences between the experimental stimuli were clearest for the last ERP potential, which presumably includes largest cognitive component. The size of the potential was significantly lower for mother than for unfamiliar voice. The results suggest that the behaviorally well-documented mutual sensitization between infant and mother and the special importance of output from mother is seen as an enhanced arousal to mother's voice and as signs of a clear memory template for own mother's voice at very early age.

Attention↗

Summation of semantic priming and complex sentence comprehension in Parkinson's disease.

Research has suggested that the integrity of semantic processing may be compromised in Parkinson's disease (PD), which may account for difficulties in complex sentence comprehension. In order to investigate the time course and integrity of semantic activation in PD, 20 patients with PD and 23 healthy controls performed a lexical decision task based on the multi-priming paradigm. Semantic priming effects were measured across stimulus onset asynchronies of 250 ms, 600 ms, and 1200 ms. Further, PD participants performed an auditory comprehension task. The results revealed significantly different patterns of semantic priming for the PD group at the 250-ms and 1200-ms SOAs. In addition, a delayed time course of semantic activation was evident for PD patients with poor comprehension of complex sentences. These results provide further support to suggest that both automatic and controlled aspects of semantic activation may be compromised in PD. Furthermore, the results also suggest that some sentence comprehension deficits in PD may be related to a reduction in information processing speed.

Acoustic Stimulation↗

Representational and executive selection resources in 'theory of mind': evidence from compromised belief-desire reasoning in old age.

Effective belief-desire reasoning requires both specialized representational capacities-the capacity to represent the mental states as such-as well as executive selection processes for accurate performance on tasks requiring the prediction and explanation of the actions of social agents. Compromised belief-desire reasoning in a given population may reflect failures in either or both of these systems. We report evidence supporting this two-process model from belief-desire reasoning tasks conducted with younger and older adult populations. When task inferential complexity is held constant, neither group showed specific difficulty with reasoning about mental state content as compared with non-mental state content. However, manipulations that systematically increase executive performance demands within belief-desire reasoning caused systematic decreases in task performance in both older and younger adult groups. Moreover, the effect of increasing executive demands was disproportionately greater in the older group. Regression analysis indicated that measures of processing speed and inhibition contributed most to explaining variance in accuracy and response times in the belief-desire reasoning tasks. These results are consistent with the idea that compromised belief-desire reasoning in old age is likely the result of age-related decline in executive selection skills that supplement core mental state representational abilities, rather than as a result of failures in the representational system itself.

Adolescent↗

Principles of rapid polymerase chain reactions: mathematical modeling and experimental verification.

Polymerase chain reaction (PCR) is an important diagnostic tool for the amplification of DNA. The PCR process can be treated as a problem in biochemical engineering. This study focuses on the development of a mathematical model of the polymerase chain reaction. The PCR process consists of three steps: denaturation of target DNA, annealing of sequence-specific oligonucleotide primers and the enzyme-catalyzed elongation of the annealed complex (primer:DNA:polymerase). The denaturation step separates the double strands of DNA; this model assumes denaturation is complete. The annealing step describes the formation of a primer-fragment complex followed by the attachment of the polymerase to form a ternary complex. This step is complicated by competitive annealing between primers and incomplete fragments including primer-primer reactions. The elongation step is modeled by a stochastic method. Species that compete during the elongation step are deoxynucleotide triphosphates dCTP, dATP, dTTP, dGTP, dUTP, and pyrophosphate. Thermal deamination of dCTP to form dUTP is included in the model. The probability for a species to arrive at the active site is based on its molar fraction. The number of random insertion events depends on the average processing speed of the polymerase and the elongation time of the simulation. The numerical stochastic experiment is repeated a sufficient number of times to construct a probability density distribution (PDF). The moment of the PDF and the annealing step products provide the product distribution at the end of the elongation step. The overall yield is compared to six experimental values of the yield. In all cases the comparisons are very good.

Algorithms↗

Autonomous detection of pulmonary nodules on CT images with a neural network-based fuzzy system.

In this paper, a novel extension of neural network-based fuzzy model has been proposed to detect lung nodules. The proposed model can automatically identify a set of appropriate fuzzy inference rules, and refine the membership functions through the steepest gradient descent-learning algorithm. Twenty-nine clinical cases involving 583 thick section CT images were tested in this study. Receiver operating characteristic (ROC) analysis was used to evaluate the proposed autonomous pulmonary nodules detection system and yielded an area under the ROC curve of Azs=0.963. The overall detection sensitivity of the proposed method was 89.3% (with p-value less than 0.001), and the false positive was as low as 0.2 per image. This result demonstrates that the proposed neural network-based fuzzy system resolves the most suitable fuzzy rules, improves the detection rate, and reduces false positives compared to other approaches. The proposed system is fully automated with fast processing speed. The studies have shown a high potential for implementation of this system in clinical practice as a CAD tool.

Algorithms↗

Effectiveness of hyperbaric oxygen in traumatic brain injury patients: A systematic review and meta-analysis.

BACKGROUND: Traumatic brain injury (TBI) is the most common neurological disorder and a leading cause of global mortality and disability. Although growing evidence suggests potential benefits of Hyperbaric Oxygen Therapy (HBOT) for TBI, its efficacy remains controversial. METHODS: We systematically searched PubMed, Embase, Cochrane Library, and Web of Science from inception to March 2026. Randomized controlled trials (RCTs) evaluating HBOT versus any comparator including sham, standard care and no treatment in adults with TBI were included. Two independent reviewers screened records, extracted data, and assessed risk of bias using the Cochrane Risk of Bias tool. Heterogeneity was assessed using the I&#xb2; statistic. Effect sizes were pooled using random/fixed-effects models per heterogeneity results. RESULTS: 8 studies involving 570 participants were included. HBOT significantly improved computerized cognitive performance (SMD = 0.23, 95% CI: 0.07-0.40, p&#x202f;=&#x202f;0.004, I&#xb2; = 0%), executive function and processing speed (SMD = -0.59, 95% CI: -0.93 to -0.26, p&#x202f;=&#x202f;0.0005, I&#xb2; = 30%), memory function (SMD = 0.33, 95% CI: 0.03-0.63, p&#x202f;=&#x202f;0.03, I&#xb2; = 0%), and sleep quality (MD = 1.98, 95% CI: 0.07-3.88, p&#x202f;=&#x202f;0.04, I&#xb2; = 65%). No significant benefits were observed for Glasgow Outcome Scale (RR = 1.57, 95% CI: 0.55-4.44, I&#xb2; = 87%), PTSD symptoms (MD = -3.05, 95% CI: -7.05-0.95, I&#xb2; = 67%), neurobehavioral symptoms (MD = -9.06, 95% CI: -32.13-14.00, I&#xb2; = 97%), and emotional distress (SMD = 0.25, 95% CI: -0.32-0.81, I&#xb2; = 85%). Most adverse events were mild and transient. CONCLUSION: HBOT demonstrates domain&#x2011;specific benefits for cognitive function and sleep quality in TBI patients, predominantly those with mild TBI. However, evidence for PTSD, neurobehavioral symptoms, and emotional distress remains uncertain. Furthermore, the applicability of current evidence to moderate-to-severe TBI populations is restricted.

Humans↗

Residual neuropsychological effects of illicit 3,4-methylenedioxymethamphetamine (MDMA) in individuals with minimal exposure to other drugs.

BACKGROUND: A substantial literature suggests that users of illicit 3,4-methylenedioxymethamphetamine (MDMA or "ecstasy") display residual cognitive deficits. Most MDMA users, however, use other illicit drugs as well, so it is difficult to be certain that these deficits are due to MDMA, as opposed to other drug use or additional confounding factors. METHODS: We administered a battery of neuropsychological tests to 23 young MDMA users who reported minimal exposure to any other drugs, including alcohol, and to 16 comparison individuals equally involved with the rave subculture, but reporting no MDMA use. We compared the groups by regression analyses adjusting for numerous potentially confounding variables. To test for a possible dose-response effect, we also performed a median split of 12 moderate MDMA users (22-50 lifetime uses) and 11 heavy users (60-450 uses), and compared these subgroups with non-users. RESULTS: MDMA users as a whole performed worse than non-users on most test measures, but these comparisons rarely reached statistical significance. This picture changed markedly in the subgroup analysis: although moderate users displayed virtually no differences from non-users on any measures, the heavy users displayed significant deficits on many measures, particularly those associated with mental processing speed and impulsivity. These differences did not appear explainable by differences in family-of-origin variables, verbal IQ, levels of depression, or time since last MDMA use. CONCLUSIONS: The presence of residual cognitive deficits, even among unusually "pure" frequent users of illicit MDMA, analyzed with adjustment for confounding variables, augments the evidence that MDMA itself, rather than some associated factor, is responsible for the deficits observed.

Adolescent↗

The development of strategy use in elementary school children: working memory and individual differences.

The current study tested the development of working memory involvement in children's arithmetic strategy selection and strategy efficiency. To this end, an experiment in which the dual-task method and the choice/no-choice method were combined was administered to 10- to 12-year-olds. Working memory was needed in retrieval, transformation, and counting strategies, but the ratio between available working memory resources and arithmetic task demands changed across development. More frequent retrieval use, more efficient memory retrieval, and more efficient counting processes reduced the working memory requirements. Strategy efficiency and strategy selection were also modified by individual differences such as processing speed, arithmetic skill, gender, and math anxiety. Short-term memory capacity, in contrast, was not related to children's strategy selection or strategy efficiency.

Age Factors↗

Anticholinesterasics in the treatment of cognitive impairment in multiple sclerosis.

Neuropsychological impairment is a common manifestation in multiple sclerosis (MS) and is found in 40-60% of patients. The pattern of cognitive impairment in MS is characterized by difficulties in recent memory, sustained attention, executive functions and information processing speed. These cognitive deficits have a significant impact on the patients' daily activities. However, there is no specific treatment available at present for cognitive disorders in MS patients. Treatment with acetylcholinesterase inhibitors (AChEI) has shown a positive effect on cognitive functions of patients with Alzheimer's disease and other conditions such as Lewy Body dementia, subcortical vascular dementia and Parkinson's disease. In this paper we review the results from studies and clinical trials aiming to demonstrate that AChEI could be a potential treatment for cognitive disorders in MS patients. Finally, we discuss future issues to take into consideration for AChEI treatments in the context of MS.

Cholinesterase Inhibitors↗

Impairment in the cognitive functioning of men with fragile X-associated tremor/ataxia syndrome (FXTAS).

Disorders associated with fragile X syndrome involve a trinucleotide (CGG) repeat expansion in the FMR1 gene. Recently, a progressive movement disorder (fragile X-associated tremor/ataxia syndrome [FXTAS]) has been identified in premutation carriers, persons with 55 to 200 CGG repeats. In addition to ataxia, action tremor, and Parkinsonism, early case reports suggested that FXTAS involves impaired cognition, but the precise nature of the impairment has not been elucidated. In this first, preliminary study of the subject, circumscribed aspects of cognitive functioning were examined in 25 men with FXTAS. Subjects' performance on the cognitive tests was compared with normative data. Scores on two measures of executive cognitive functioning showed a high prevalence of substantial impairment. Capacity for inhibition was severely affected in one-quarter of this highly educated sample; information processing speed was profoundly impaired in most subjects. Although mean verbal and performance IQ scores were not significantly different from the general population, they were quite low given the sample's educational level. Cognitive and functional impairment was greater for men with more CGG repeats, although number of repeats was not associated with age of onset of either tremor or ataxia. The results provide evidence that FXTAS involves marked impairment of executive cognitive abilities.

Aged↗

Sources of declarative memory impairment in bipolar disorder: mnemonic processes and clinical features.

BACKGROUND: There is mounting evidence that declarative memory processes are impaired in patients with bipolar disorder. However, predictors of the observed impairment are not well understood. This study seeks to: (i) better characterize the nature of declarative memory impairment in bipolar disorder, and (ii) determine the relationship between clinical variables and memory function in bipolar disorder. METHODS: 49 adult patients with bipolar disorder in varying mood states and 38 demographically matched healthy participants completed a comprehensive neurocognitive battery assessing general cognitive functioning, processing speed, and declarative memory. The California verbal learning test was used to characterize learning and memory functions. RESULTS: Although patients with bipolar disorder utilized a similar semantic clustering strategy to healthy controls, they recalled and recognized significantly fewer words than controls, suggesting impaired encoding of verbal information. In contrast, lack of rapid forgetting suggests relative absence of a storage deficit in bipolar patients. While severity of mood symptomatology and illness duration were not associated with task performance, gender and family history significantly affected memory function. CONCLUSIONS: Results suggest that declarative memory impairments in bipolar patients: (1) are consistent with deficits in learning, but do not appear to be related to different organizational strategies during learning, and (2) do not appear to be secondary to clinical state, but rather may be associated with the underlying pathophysiology of the illness.

Adult↗