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PubMed1996

Cognitive function and duration of rooflessness in entrants to a hostel for homeless men.

BACKGROUND: Four previous studies of homeless adults have yielded conflicting results regarding the presence of cognitive impairment. METHOD: A consecutive series of 80 roofless entrants to a hostel for homeless men were sampled and 62 (76%) completed a range of assessments, including measures of mental state, cognitive functions and substance use. RESULTS: Estimated premorbid IQ (mean = 96), current IQ (mean = 84) and cognitive speed were significantly lower than the norm. There was a significant IQ drop in all diagnostic groups. IQ drop, but not current IQ, correlated with duration of rooflessness. Those with schizophrenia or alcohol problems were roofless for longest. Alcohol misuse did not correlate with IQ drop, excepting alcohol withdrawal symptoms in those with schizophrenia. CONCLUSION: The hypothesis that low IQ is a risk factor for rooflessness is supported. However, length of rooflessness was more closely related to IQ drop than to current IQ, suggesting that some third factor may be affecting both rooflessness and intellectual functioning. Roofless men with schizophrenia or alcohol problems may be especially at risk of long-term rooflessness.

Adult↗

PubMedDate not supplied

[Effects of antidepressants on cognitive functions. Review of the literature].

In this review the authors propose to study the impact of antidepressants on attention, memory and motor functions in healthy volunteers and depressed patients on single and long-term administration. After reviewing the principal cognitive functions, we examine the actual investigation means to conclude that the Critical Flicker Fusion Test (CFFT) is one of the most drug-sensitive tests. It permits a categorization in: sedative antidepressants that in single administration lower CFFT; compounds with no effect on CFFT and no deleterious cognitive effect; and finally substances that raise CFFT and may have psychostimulating properties. On single administration amitriptyline is the most sedative antidepressant on attention or motor level. It seems to produce negative effects on memory level. However, experimental trials give contradictory results. Imipramine in single administration also has sedative effects on memory and car driving capacity. However divergent results of experimental trials do not allow any conclusions of a clearcut negative cognitive effect. Memory impairments with imipramine appear at administration levels of 150 mg. Mianserin has a sedative impact on attention and motor level at low doses (10 mg). Among the tricyclics, nortriptyline has a highly dose dependent sedative effect that has been shown on attention tests (Time Reaction:TR, Digit Symbol Substitution Test: DSST). Among non-tricyclic compounds, doxepine lowers attention and motor performances. Maprotiline (75 mg) lowers CFFT and has a dose dependent effect. Trazodone also has a negative impact on attention tests. Finally viloxazine lowers CFFT but does not impair other attention or motor tests on a 100 mg doses. Buspirone, lofepramine, midalcipran and zimelidine are antidepressants with no effect on CFFT and do not have any positive or negative cognitive effect. On the other hand nomifensine, paroxetine and fluoxetine raise CFFT in healthy volunteers on single administration. Improvement of CFFT performances was found in an isolated manner for nomifensine and paroxetine on 30 mg doses with no other memory or motor effects. MAO-Inhibitors do not impair attention or motor function; thus moclobemide has no negative impact on memory, attention or car driving tests. Cognitive impact of antidepressants in depressive patients seems the same with those of healthy volunteers on single administration. In long-term administration antidepressants have different effects in healthy and depressed subjects. In healthy volunteers cognitive effects of most compounds are normalized after the second week of treatment. However, attention and motor performances with amitriptyline are normalized after 3 weeks of treatment. Sedative motor or cognitive effects of imipramine do not exceed 8 days.(ABSTRACT TRUNCATED AT 400 WORDS)

Antidepressive Agents↗

PubMed1997

The influence of smoking on reward responsiveness and cognitive functions: a natural experiment.

AIMS: To investigate the effects of (a) nicotine abstinence and (b) cigarette smoking after abstinence, on reward responsiveness and cognitive functions which are putatively dependent on activity in the dopaminergic system implicated in smoking. DESIGN: During Ramadhan, Muslim smokers elected to abstain from smoking either for the whole month (RAMQUIT) or during daylight hours (DAYQUIT). These groups, and non-smokers (NOSMOKE), were assessed on two occasions 6 hours apart (TEST1 and TEST2). DAYQUIT participants had abstained for 6 hours at TEST1 and smoked a single cigarette immediately prior to TEST2. RAMQUIT participants had abstained for at least 10 days prior to TEST1 and remained abstinent at TEST2. NOSMOKE and RAMQUIT participants are a small snack prior to TEST2 to control for non-specific consummatory effects. SETTING: TEST1 was conducted at the mosque and TEST2 in participants' homes. PARTICIPANTS: All were male; mean age was 26.7 years. Modal cigarette consumption prior to Ramadhan by both the 13 DAYQUIT and the 11 RAMQUIT smokers was 21-30 per day. DAYQUIT subjects rated themselves as more dependent. MEASUREMENTS: The Card Arranging Reward Responsivity Objective Test (CARROT), testing behavioural responsiveness to small financial incentive; digit span, measuring attention; verbal fluency, indexing frontal lobe function; and the two-choice guessing test (2CGT; at TEST1 only), measuring response stereotypy. FINDINGS: At TEST1, compared with non-smokers, both smoking groups showed greater stereotypy (2CG) and lower reward responsiveness (CARROT). DAYQUIT participants improved on all measures after smoking a single cigarette. No marked changes were seen in the other groups. CONCLUSION: These data suggest that (i) abstaining smokers have impaired dopaminergic function and (ii) nicotine consumption may boost their dopaminergic activity.

Adult↗

PubMed2005

Long-term effects of sequential cortical infarcts on scar size, brain volume and cognitive function.

Focal ischemia induces long-term pathophysiological consequences in widespread brain areas. Here we analyzed long-term effects of sequential cortical lesions on brain volume and cognitive function. Rats received either single photothrombotic lesions in the forelimb sensorimotor cortex (SL) or two lesions in sequence either immediately (DL0), 2 days (DL2), 7 days (DL7), or 10 days (DL10) after the first surgery in the homotopic contralateral area. Infarct and global brain volume were measured 7 days (SL and DL2 groups) and one month (all groups) after the last period of ischemia. In the weeks following a stroke, the single lesion shrank considerably. This shrinkage was accentuated by a further lesion received either earlier or later. Thirty-one days after obtaining the second lesion, the lesion scars on both sides had a mean volume of 5.8 +/- 2.3 mm3 in DL2 as compared to 8.5 +/- 3.5 mm3 in SL-animals. In addition, there was a super-additive loss of residual brain volume by 2.2-8.0% in each hemisphere in animals with sequential lesions. In the watermaze, this loss of brain volume corresponded to a slight but significant impairment in performance. The present study revealed a complex interaction of lesions in animals with sequential strokes associated with global reduction of brain volume and cognitive impairment indicating degenerative processes beyond the lesions itself.

Animals↗

PubMed1998

Assessing cognitive functions in tree shrews: visuo-spatial and spatial learning in the home cage.

We developed a holeboard paradigm to investigate the cognitive abilities of tree shrews (Tupaia belangeri). The design allows animals to be tested in their homecages, which reduces possible confounding and stress factors, such as transfer to a special testing arena, food deprivation or other restraints. Nine male tree shrews performed four visuo-spatial and one spatial trial per day in two blocks of 5 consecutive days. Tree shrews needed only 1 day, that is five trials, to learn the complex holeboard paradigm. From the second day onwards the learning scores remained almost stable. To demonstrate the applicability of this paradigm in studies on the influence of stress on cognitive functions, three animals were subjected to and tested under psychosocial stress conditions on 2 consecutive days. Since the experimental animals also performed the task under stressful conditions the home cage holeboard paradigm is a valid tool to study the development of stress induced cognitive impairments.

Animals↗

PubMed1995

Cognitive functioning in chronically hospitalized schizophrenic patients: age-related changes and age disorientation as a predictor of impairment.

Although schizophrenic patients manifest cognitive impairments, there is considerable variability across patients in the severity of this impairment. Very chronic patients with a poor outcome, particularly geriatric patients, manifest the most severe impairments, which have often been characterized as resembling dementia. This study examined age-related changes in cognitive functioning in a sample of schizophrenic patients (n = 393) ranging from 25 to 95 years of age, with a specific focus on identifying aspects of performance that were impaired in the youngest patients and preserved in the oldest patients. Age disorientation was examined in detail because it was previously found to predict global intellectual impairment in chronic patients. All 22 test items changed linearly over time (with age), with aspects of orientation, concentration, and delayed recall most impaired in young patients and naming and sentence repetition most preserved in the oldest patients. Age disoriented patients had more severe cognitive impairments at each age and the age-related changes in global impairment were more severe for these patients. The prevalence of age disorientation was consistent with previous reports and a one-year retest of the sample found that age disorientation was extremely stable over time within patients. The types of functions that are preserved in the oldest patients underscore previous findings of differences between geriatric schizophrenic patients and patients with degenerative diseases and the stability of age disorientation suggests that it is a trait of a subset of schizophrenic patients, those who appear to have the most severely declining course of illness.

Adult↗

PubMed2003

Cognitive functioning in younger and older HIV-1-infected adults.

In young adults, a major neurologic complication of HIV-1 infection is cognitive motor impairment. Epidemiologic findings suggest that increasing age is a significant risk factor for HIV-1-associated dementia as the AIDS-defining illness. Findings from the few studies that have directly measured cognition in younger and older HIV-1-infected adults, however, have been mixed, in part, because of small sample sizes and other methodologic differences between studies. The authors present preliminary findings on cognitive functioning in symptomatic HIV-1-infected younger (aged 20-39 years) and older (aged 50 years or older) adults. Independent of age, HIV-1 infection was accompanied by learning and memory retrieval deficits, which were significantly associated with high plasma viral loads in the young adults. Relative to the younger and older HIV-1-negative (HIV-1-) groups, only the younger HIV-1-positive (HIV-1+) group had significantly longer reaction times (RTs). Within the older HIV-1+ group, however, longer simple and choice RTs were significantly correlated with higher viral loads and lower CD4 cell counts. Although HIV-1 infection affects cognition independent of age, longitudinal studies involving large numbers of older individuals are needed to determine whether there are age differences in the prevalence, nature, and severity of HIV-1-associated cognitive dysfunction.

Acquired Immunodeficiency Syndrome↗

PubMed2000

Effects of lamotrigine on nocturnal sleep, daytime somnolence and cognitive functions in focal epilepsy.

OBJECTIVES: The aim of our study was to evaluate possible changes in nocturnal sleep, daytime somnolence and cognitive functions induced by add-on therapy with lamotrigine (LTG). MATERIAL AND METHODS: Thirteen patients affected by seizures resistant to common antiepileptic drugs (AEDs) underwent nocturnal polysomnographic monitorings, daytime somnolence evaluations and a neuropsychological battery before and after 3 months of treatment with LTG. RESULTS: With LTG therapy we observed a significant increase in REM sleep and a significant reduction in the number of entries into REM and stage shifts. No significant correlation was observed between the decrease in nocturnal epileptiform activity and the increase in REM sleep. Other sleep parameters were unmodified. No significant changes were observed in daytime somnolence and in cognitive performances. CONCLUSION: LTG may produce positive effects on epileptic seizures and interictal abnormalities without interfering negatively on REM sleep, with improvement of sleep stability and without changes in daytime somnolence and neuropsychological performances. For these reasons it could be an important drug for improving epileptic patients' quality of life.

Adolescent↗

PubMed2005

The relationship between self-awareness of neurobehavioral symptoms, cognitive functioning, and emotional symptoms in multiple sclerosis.

OBJECTIVE: To examine self-awareness of neurobehavioral symptoms in multiple sclerosis (MS) across three domains of function (apathy, disinhibition, and executive control), and examine the relationship between self-awareness and cognitive functioning. METHODS: Twenty-six individuals with MS completed neuropsychological testing, measures of emotional functioning, and self-ratings of neurobehavioral symptoms using the Frontal Systems Behavior Scale (FrSBe), a 46-item questionnaire with subscales assessing frequency of symptoms in executive dysfunction, disinhibition, and apathy. Informants' ratings of the FrSBe were also obtained. Decreasing differences between patient and informant reports on each subscale of the FrSBe (concordance) indicate higher levels of self-awareness. RESULTS: Results showed significant positive correlations between cognitive abilities and self-awareness of executive dysfunction and disinhibition. In contrast, affect symptomatology (measures of anxiety and depression) were negatively correlated with self-awareness of executive dysfunction. CONCLUSIONS: Level of self-awareness of neurobehavioral symptoms in MS is related to level of cognitive impairment In addition, symptoms of depression and anxiety reduced the accuracy of self-reporting. Thus, a clinician who relies on self-reports in creating an evaluation and treatment plan should consider the patient's cognitive and emotional states.

Adult↗

PubMed2005

Neuroimaging and cardiac correlates of cognitive function among patients with cardiac disease.

In the present study, we examined the relationships between whole brain volume (WBV), subcortical hyperintensities (SH), indices of cardiac disease and cognitive function in nondemented cardiac patients with evidence of mild cerebrovascular disease. A total of 27 individuals with evidence of cardiac disease underwent neuropsychological examination, neuroimaging, and cardiac assessment. Cognition was assessed with the Dementia Rating Scale-2 (DRS). WBV and SH were quantified using a semi-automated thresholding program based on MRI. Correlational analyses revealed that WBV predicted performance on the overall DRS score, the attention subscale and the initiation/perseveration scale. SH were significantly associated with performance on the attention subscale, and the initiation/perseveration subscale. Regression analyses revealed that SH accounted for most of the variance in the initiation/perseveration scale, whereas WBV accounted for most of the variance in the attention scale. The only cardiac structural or functional variable related to the neurological indices was aortic diameter, which was strongly related to both neuroimaging variables, as well as performances on the DRS attention and initiation/perseveration subscales. Our results highlight the importance of overall brain parenchyma in determining cognitive status among patients at risk for cognitive decline and suggest that select indices of structural cardiac morphology may be related to the early phases of cerebrovascular disease and cognitive status.

Aged↗

PubMed2006

Urban neighborhood context, educational attainment, and cognitive function among older adults.

Existing research has not addressed the potential impact of neighborhood context--educational attainment of neighbors in particular--on individual-level cognition among older adults. Using hierarchical linear modeling, the authors analyzed data from the 1993 Study of Assets and Health Dynamics Among the Oldest Old (AHEAD), a large, nationally representative sample of US adults born before 1924. Data from participants residing in urban neighborhoods (n = 3,442) were linked with 1990 US Census tract data. Findings indicate that 1) average cognitive function varies significantly across US Census tracts; 2) older adults living in low-education areas fare less well cognitively than those living in high-education areas, net of individual characteristics, including their own education; 3) this association is sustained when controlling for contextual-level median household income; and 4) the effect of individual-level educational attainment differs across neighborhoods of varying educational profiles. Promoting educational attainment among the general population living in disadvantaged neighborhoods may prove cognitively beneficial to its aging residents because it may lead to meliorations in stressful life conditions and coping deficiencies.

Aged↗

PubMed2001

Improvement of cognitive functions after cobalamin/folate supplementation in elderly patients with dementia and elevated plasma homocysteine.

OBJECTIVES: To investigate the effect of cobalamin/folate supplementation on cognitive function in elderly patients with dementia. METHOD: The cobalamin/folate status of the patients was evaluated by measuring plasma homocysteine, serum methylmalonic acid, serum cobalamin and blood folate. Thirty-three patients were studied and repeatedly assessed with the Mini-Mental State Examination (MMSE) and 'A short cognitive performance test for assessing memory and attention' (SKT) during vitamin substitution. RESULTS: Patients with mild-moderate dementia and elevated plasma homocysteine levels improved clinically with increased test scores after vitamin substitution, while severely demented patients and patients with normal plasma homocysteine levels did not improve clinically. CONCLUSIONS: Plasma homocysteine may be the best marker for detecting treatable cobalamin/folate deficiency in patients with dementia.

Aged↗

PubMedDate not supplied

The heritability of level and rate-of-change in cognitive functioning in Danish twins aged 70 years and older.

To investigate heritable influences on overall level and rate-of-change in cognitive ability, biometric growth models were fit to cognitive data from nearly 1000 Danish twins age 70 years and older. Twins are participants in the ongoing Longitudinal Study of Aging Danish Twins, a cohort-sequential study of twins assessed every 2 years for up to four waves. Cognitive ability was assessed by five brief cognitive tasks: a fluency measure, forward and backward digit span, and immediate and delayed list recall. Model-fitting results indicated that although the overall level of cognitive functioning was highly heritable (h(2) = .76, 95% confidence interval of .68 to .82), the rate of linear change was not (h(2) = .06, 95% confidence interval of .00 to .57). These findings suggest that the search for specific genes might reasonably focus on average level of cognitive performance, whereas specific environmental influences might account for cognitive change.

Aged↗

PubMed2003

The Maudsley early onset schizophrenia study: cognitive function in adolescents with recent onset schizophrenia.

Neuropsychological function has been little studied early in the course of adolescent onset schizophrenia. The present study investigated cognitive function in adolescents with recent onset schizophrenia (n=20) and healthy controls (n=21), employing a comprehensive battery of intelligence, memory and executive function paradigms. Relative to the control group, the patients showed significant or near-significant deficits in more than half of the cognitive variables we examined. A substantial proportion of this broadly based neuropsychological deficit could be accounted for, at least in part, by a mild decrement in general intellectual ability. However, deficits in general and verbal memory remained highly significant after co-varying for IQ.

Adolescent↗

PubMed2006

Cognitive functioning in delusions: a longitudinal analysis.

BACKGROUND: This study explored the longitudinal course of the relationship between delusions and different aspects of cognitive functioning. METHODS: Deluded patients were compared to psychiatric and non-clinical controls on three tasks: negative priming, a probabilistic judgement task (the 'beads' task), and the pragmatic inference task (PIT). All groups were tested at two time points, once when actively symptomatic, and once when in remission. RESULTS: Deluded individuals exhibited a 'jump-to-conclusions' (JTC) reasoning bias: i.e., they made decisions on the basis of limited evidence and were more likely to revise their estimates when faced with disconfirmatory evidence. This JTC bias remained stable over time, although probability judgments seemed to normalise in remission. No deficits in cognitive inhibition were found on negative priming. The deluded group displayed an excessive self-focus on the PIT at both time points, but did not show a depressive attributional style. Only a small sub-sample, characterised by the "bad-me" type of paranoia [Trower & Chadwick, 1995 Clinical Psychology: Science and Practice, 2, 263-278.], demonstrated depressive schemas when symptomatic, but no longer did so when remitted. Few relationships were found between tasks, suggesting that different areas of functioning are relatively independent. The only measures associated with delusion symptom scores were from the 'beads' task. CONCLUSIONS: Overall these findings suggest that the JTC bias is a stable factor associated with delusional thinking, while the depressive attributional style characteristic of a small sub-sample of paranoid patients fluctuates with delusional course.

Adult↗

PubMed2004

Effect of low doses of ionising radiation in infancy on cognitive function in adulthood: Swedish population based cohort study.

OBJECTIVE: To determine whether exposure to low doses of ionising radiation in infancy affects cognitive function in adulthood. DESIGN: Population based cohort study. SETTING: Sweden. PARTICIPANTS: 3094 men who had received radiation for cutaneous haemangioma before age 18 months during 1930-59. MAIN OUTCOME MEASURES: Radiation dose to frontal and posterior parts of the brain, and association between dose and intellectual capacity at age 18 or 19 years based on cognitive tests (learning ability, logical reasoning, spatial recognition) and high school attendance. RESULTS: The proportion of boys who attended high school decreased with increasing doses of radiation to both the frontal and the posterior parts of the brain from about 32% among those not exposed to around 17% in those who received > 250 mGy. For the frontal dose, the multivariate odds ratio was 0.47 (95% confidence interval 0.26 to 0.85, P for trend 0.0003) and for the posterior dose it was 0.59 (0.23 to 1.47, 0.0005). A negative dose-response relation was also evident for the three cognitive tests for learning ability and logical reasoning but not for the test of spatial recognition. CONCLUSIONS: Low doses of ionising radiation to the brain in infancy influence cognitive abilities in adulthood.

Adolescent↗

PubMed2001

Cognitive functioning and the early development of PTSD.

Cross-sectional studies of chronic PTSD reveal deficits in verbal memory. We studied cognitive functioning and its relationship to current and subsequent PTSD severity during an early phase of trauma response. Thiry-eight participants with traumatic injuries and only posttrauma incident psychopathology were evaluated shortly after admission to a Level I Trauma Center Neuropsychological measures were obtained at baseline and assessment of PTSD and other psychiatric disorders was conducted at baseline and follow-up, 6 weeks later. Significant negative correlations were found for follow-up PTSD severity with delayed recall and retroactive interference. These relationships were not significant for and were independent of baseline PTSD severity. Relative deficits in select areas of verbal memory after a trauma may confer greater risk for developing PTSD.

Adult↗

PubMed2003

Absence of adverse effects of severe hypoglycemia on cognitive function in school-aged children with diabetes over 18 months.

OBJECTIVE: Some children with type 1 diabetes may be at risk of cognitive impairments, but mechanisms of this effect have not been confirmed. The objective of this study was to determine whether severe hypoglycemia (SH) in children with type 1 diabetes is associated with cognitive decline over 18 months. RESEARCH DESIGN AND METHODS: A sample of 142 6- to 15-year-old children with type 1 diabetes (mean age 11.6 +/- 2.7 years) enrolled in a trial of intensive therapy (IT) or usual care (UC) were tested with the Das-Naglieri Cognitive Assessment System at baseline and after 9 and 18 months. Episodes of SH were recorded by parents and reported promptly for verification by study nurses. HbA(1c) was measured quarterly. RESULTS: Over 18 months, 58 of 142 patients (41%) experienced 111 SH episodes, with a RR of SH of 1.12 for IT over UC. Neither occurrence nor frequency of SH was associated with decline in full-scale intelligence quotient (IQ), standard scores for planning, attention, simultaneous processing, or successive processing, or scaled scores on any of eight subtests. The same findings emerged when only patients who had experienced hypoglycemic seizures or coma were included in the SH group for analyses. These effects persisted when the child's age, sex, type 1 diabetes duration, and age at diagnosis were controlled statistically. HbA(1c) during the trial was not associated with cognitive changes. CONCLUSIONS: SH did not induce adverse changes in the measures of cognitive function administered to 6- to 15-year-old children with type 1 diabetes in this study. Although SH should be avoided in all children with diabetes, these episodes did not have adverse effects on cognition in this age-group over 18 months.

Adolescent↗