Spatial Span Test Research Articles

Neurocognitive Functions and Brain Volume in Patients with Endogenous Cushing's Syndrome Before and After Curative Surgery.

Introduction:Cushing's syndrome (CS) leads to various neuropsychiatric manifestations due to structural and functional changes of the brain and contributes significantly in the impairment of health-related quality of life.Aim and Objective:This study is conducted with aims to evaluate neurocognitive functions and brain volume in patients with endogenous Cushing's syndrome before and after curative surgery.Methods:The diagnosis of CS was made by clinical features, abnormal cortisol dynamics, ACTH levels, and imaging studies. Neuropsychiatric tests (Beck depression Index, Spatial span test, PGI memory scale, Color trail test, Verbal fluency test), and Brain volume (Bi-caudate and third ventricular diameter) were done before and after curative surgery.Results:Fifteen patients of CS were included for the study; all patients underwent curative surgery, neuropsychiatric assessment, and brain volume measurements. Nine patients were followed successfully till remission and repeat evaluation of these patients was done. Depression was the most common neuropsychiatric illness. Severity of depression positively correlated with 0800 h plasma cortisol and ACTH. Patients with higher severity of depression had maximum improvement after curative surgery. Significant decrease in the third ventricular, as well as bicaudate diameter, was observed after curative surgery (P < 0.01).Conclusion:Neuropsychiatric functions and structural brain changes reverse after curative surgery in patients with endogenous CS, however, long term follow-up is required to know whether these changes reverse completely or not.

Polymorphism in the LASP1 gene promoter region alters cognitive functions of patients with schizophrenia

Schizophrenia’s pathogenesis remains elusive. Cognitive dysfunction is the endophenotype and outcome predictor of schizophrenia. The LIM and SH3 domain protein (LASP1) protein, a component of CNS synapses and dendritic spines, has been related to the N-methyl-D-aspartate receptor (NMDAR) dysfunction hypothesis and schizophrenia. A single-nucleotide polymorphism (rs979607) in the LASP1 gene promoter region has been also implicated in schizophrenia susceptibility. The aim of this study was to investigate the role of the LASP1 rs979607 polymorphism in the cognitive functions of patients with schizophrenia. Two hundred and ninety-one Han Taiwanese patients with schizophrenia were recruited. Ten cognitive tests and two clinical rating scales were assessed. The scores of cognitive tests were standardized to T-scores. The genotyping of the LASP1 rs979607 polymorphism was performed using TaqMan assay. Among the 291 patients, 85 were C/C homozygotes of rs979607, 141 C/T heterozygotes, and 65 T/T homozygotes, which fitted the Hardy-Weinberg equilibrium. After adjusting age, gender, and education with general linear model, the C/C homozygotes performed better than C/T heterozygotes in overall composite score (p = 0.023), Category Fluency test (representing processing speed and semantic memory) (p = 0.045), and Wechsler Memory Scale (WMS)-III backward Spatial Span test (p = 0.025), albeit without correction for multiple comparisons for the latter two individual tests. To the best of our knowledge, this is the first study suggesting that the genetic variation of LASP1 may be associated with global cognitive function, category verbal fluency, and spatial working memory of patients with schizophrenia. The finding also lends support to the NMDAR dysfunction hypothesis of schizophrenia. More studies with longitudinal designs are warranted.

B-04 Combining tDCS and Cognitive Training for People with Severe Mental Illness: Preliminary Feasibility and Acceptability Findings

Abstract Objective Technological advances in neuromodulation and cognitive remediation provide opportunities to develop novel interventions, though a critical first determination is whether such treatments are feasible and acceptable to participants. This study evaluated a combined transcranial direct current stimulation (tDCS) and computerized cognitive training intervention for individuals with severe mental illness; we examined participant recruitment, retention, and adherence to the interventions, along with qualitative feedback. Method Participants included adults with schizophrenia-spectrum or bipolar disorder and impaired working memory (performance ≤1 standard deviation below average of healthy individuals on a spatial span or letter-number span test). In this randomized crossover study, all participants received the combined intervention (ten tDCS sessions in the clinic concurrent with cognitive training), and ten hours of at-home training, and completed neuropsychological and clinical assessments at three time points. Results To date, thirteen participants provided informed consent. Seven participants were screened out; five exceeded the cognitive cutoff and one did not meet the diagnostic criterion. No remaining participants have withdrawn prior to study completion. Four participants completed all tDCS sessions, and one completed 80%. No tDCS session has been discontinued. At-home training has proven more challenging; only one participant completed all ten hours, and three did not complete any at all. Participant feedback has been positive; all expressed satisfaction with both treatments though some said symptoms or busy schedules interfered with at-home training. Conclusions Combining tDCS with computerized cognitive training appears feasible and acceptable. Strategic recruitment efforts to capture those with cognitive impairment appears necessary, as well as troubleshooting barriers to at-home training.

Who will benefit from computerized cognitive remediation therapy? Evidence from a multisite randomized controlled study in schizophrenia.

Computerized cognitive remediation therapy (CCRT) is generally effective for the cognitive deficits of schizophrenia. However, there is much uncertainty about what factors mediate or moderate effectiveness and are therefore important to personalize treatment and boost its effects. In total, 311 Chinese inpatients with Diagnostic and Statistical Manual of Mental Disorders-IV schizophrenia were randomized to receive CCRT or Active control for 12 weeks with four to five sessions per week. All participants were assessed at baseline, post-treatment and 3-month follow-up. The outcomes were cognition, clinical symptoms and functional outcomes. There was a significant benefit in the MATRICS Consensus Cognitive Battery (MCCB) total score for CCRT (F1,258 = 5.62; p = 0.02; effect size was 0.27, 95% confidence interval 0.04-0.49). There were no specific moderators of CCRT improvements. However, across both groups, Wisconsin Card Sort Test improvement mediated a positive effect on functional capacity and Digit Span benefit mediated decreases in positive symptoms. In exploratory analyses younger and older participants showed cognitive improvements but on different tests (younger on Symbol Coding Test, while older on the Spatial Span Test). Only the older age group showed MSCEIT benefits at post-treatment. In addition, cognition at baseline negatively correlated with cognitive improvement and those whose MCCB baseline total score was around 31 seem to derive the most benefit. CCRT can improve the cognitive function of patients with schizophrenia. Changes in cognitive outcomes also contributed to improvements in functional outcomes either directly or solely in the context of CCRT. Age and the basic cognitive level of the participants seem to affect the cognitive benefits from CCRT.

The effect of transcranial direct current stimulation on the short-term spatial memory in healthy volunteers

Introduction. Transcranial direct current stimulation (tDCS) is a method of non-invasive brain stimulation. The application of a weak, subthreshold direct current on the cerebral cortex leads to a change in cortical neuron activity, which continues for a certain amount of time after exposure. The main mechanism of this effect is subthreshold changes in the membrane potential, while the after-effect phenomenon is associated with the influence of tDCS on synaptic plasticity. Study objective. To examine the effect of tDCS of the posterior parietal cortex on certain types of spatial memory with the electrodes positioned P3– P4+ and P3+ P4–. Materials and methods. The study included 18 healthy volunteers (10 men and 8 women) aged 18–23 years. The experiment used stimulation points P3 and P4 according to the 10–20 international electrode positioning system. Stimulation was performed using a direct current of 0.7 mA for 20 min. The study participants underwent three stimulation sessions (P3– P4+, P3+ P4–, P30 P40) in a randomized order with an interval of 3 days between them. After each session, the state of their short-term spatial memory was assessed using the Spatial Memory (categorical spatial memory) and Spatial Span (coordinate spatial memory) tests by Cambridge Brain Sciences, as well as the subjective effect of tDCS. Results. There were no statistically significant differences in the results of neuropsychological tests between ‘active’ stimulation (P3– P4+ and P3+ P4–) and sham stimulation. The lack of effect may be due to the use of insufficient current (0.7 mA) or other factors (duty cycle, electrode location, stimulation time, etc.). No adverse effects of stimulation were reported. Conclusion. tDCS with 0.7 mA current does not affect spatial memory in healthy people when using P3– P4+ and P3+ P4– electrode mountings.

Investigating the effect of daily sleep on memory capacity in college students.

Sleep is a natural periodic state of rest for body and mind and daily sleep affects physical and mental health. However, it is essential to address intensity of sleep characteristics affecting the memory capacity of humans positively or negatively. Using wearable devices to observe and assess the effect of daily sleep on memory capacity of college students. This study assessed the daily sleep characteristics and memory capacity of 39 college students who used wrist-worn devices. The spatial span test (SST) was used to evaluate the memory capacity. The study indicated a negative correlation between memory capacity and awake count on the test date and during the week before the test date (r=-0.153 (95% CI: -0.032, -0.282), r=-0.391 (95% CI: -0.520, -0.235), respectively). However, the minutes asleep on the test date and during the week before the test date positively affected memory capacity (r= 0.127 (95% CI: 0.220, 0.025), r= 0.370 (95% CI: 0.208, 0.500), respectively). In addition, spending ⩾ 6 hours and 42 minutes asleep on the test date or ⩾ 6 hours and 37 minutes asleep per day on average during the week before the test date resulted in a better memory capacity. A lower awake count led to a higher memory capacity in college students, as did more minutes asleep.

Cognitive and behavioural dispositions in offspring at high risk for alcoholism.

Offspring with family history of alcoholism are considered to be at high risk for alcoholism. The present study sought to expand our understanding of cognitive and behavioural dispositions associated with executive control and self-regulation in alcohol naïve offspring with and without family history of alcoholism. Sample comprised of alcohol naive offspring in two groups: (i) at high risk (n = 34) and (ii) at low risk for alcoholism (n = 34). Both groups were matched on age (+/-1 year), education (+/-1 year) and gender. Measures used were: Mini-International Neuropsychiatric Interview, Family Interview for Genetic Studies, Socio-demographic Data Sheet, Annett's Handedness Questionnaire, Barratt's Impulsiveness Scale-version 11, Digit Span Test, Spatial Span Test, Tower of London, Wisconsin Card Sorting Test, Iowa Gambling Task (IGT) and Game of Dice Task (GDT). Results showed that alcohol naive offspring at high risk for alcoholism reported significantly high impulsivity and demonstrated significant differences on executive functions and decision making tasks. Correlation analysis revealed that high impulsivity was significantly associated with poor performance on explicit decision making task (GDT) and executive function task (WCST). There was no significant correlation between two decision making tasks (IGT and GDT) in both groups and performance on IGT was not significantly associated with impulsivity and executive functions. The present study indicates cognitive and behavioural dispositions in alcohol naive offspring at high risk for alcoholism and support the sub-optimal balance between reflective and impulsive system responsible for addiction. Furthermore, present study supports separability between two different types of decision making tasks.

S68. Impulse control impairment relationships with Visfatin and body composition indices in patients with type 2 Diabetes Mellitus

Introduction Diabetes Mellitus is associated with a higher incidence of neurobehavioral symptoms, fatigue and cognitive impairment. Thus we aimed to study and compare serum visfatin levels, cognitive functions, fatigue and body composition in patients with type 2 Diabetes Mellitus (T2DM) and healthy subjects. Methods Sixty-five participants (31 T2DM and 34 controls) from outpatient clinics were recruited in this observational case-control study. Clinical and demographic characteristics were measured for each participant and cognition was assessed by Stop Signal Task (SST) and Intra-Extra Dimensional Set Shift (IED) and Spatial Span (SSP) tests using Cambridge Neuropsychological Automated Battery (CANTAB). Blood samples were collected to measure visfatin and glycosylated hemoglobin (HbA1c). Body composition was analyzed by Bio Impedance Analyzer (BIA). Results Cognitive impairments, in the form of longer reaction times and impaired spatial planning, were detected in T2DM. SST Stop Signal Reaction Time (SST SSRT) (p = 0.03), IED erros (p = 0.0412), SST Direction Errors on STOP and GO trials (p = 0.04) were significantly delayed in T2DM versus controls. The SSP length was significantly lower in T2DM indicating impaired working memory capacity (p = 0.02). In general linear model degree of glycemia was found to be independently predictive of impulse control. Visceral fat was also found to be significantly correlated with proportion of total IED errors (r = 0.333, p = 0.0412). Conclusion The results of this study show that T2DM patients have impaired cognitive functions in terms flexibility of impulse control, attention, and working memory capacity. Moreover, the degree of glycemia may be independently predictive of impulse control in these subjects.

Who Will Benefit from Computerized Cognitive Remediation Therapy? Evidence from a Multisite Randomized Controlled Study in Schizophrenia

Background: Computerized Cognitive Remediation Therapy (CCRT) is generally effective for the cognitive deficits of schizophrenia. However, there is much uncertainty about what factors mediate or moderate effectiveness and are therefore important to personalize treatment and boost its effects. Methods: In a multisite, single-blind, randomized clinical trial, 311 Chinese inpatients with a diagnosis of schizophrenia were recruited and randomized to receive CCRT (n = 196) or active control (n = 115) for 12 weeks with 4-5 sessions per week. All participants were assessed at baseline, post-treatment and 3-month follow-up. The main outcome was cognition (MATRICS Consensus Cognitive Battery total score, MCCB), and secondary outcomes included clinical symptoms (PANSS) and functional outcomes (UPSA, NOSIE and self-esteem). Findings: There was a significant benefit in the primary outcome (MCCB total score) in favour of CCRT (F (1, 258) = 5.62; p = 0.02; effect size was 0.27, 95% CI, 0.04-0.49). Wisconsin Card Sort Test change scores mediated a positive effect on functional capacity (UPSA score) solely in the context of CCRT. Both younger and older participants showed cognitive improvements but on different tests. Younger participants showed improvement in Symbol Coding Test, while older participants showed in Spatial Span Test. On the MSCEIT only the older age group showed benefits at post-treatment. In addition, the effect of cognitive remediation on MCCB total score was negatively correlated with the baseline level of MCCB total score. Participants with an MCCB baseline total score around 31 seem to derive the most cognitive benefits. Interpretation: CCRT can improve the general cognitive function of schizophrenia. The changes in cognitive outcomes also contributed to improvements in functional outcomes either directly or solely in the context of CCRT. Age and the basic cognitive level of the participants seem to affect the cognitive benefits from CCRT. Clinical Trial Number: This trial is registered with Chinese Clinical Trials.gov, identifier ChiCTR-TRC-08000249. Funding Statement: This study was partially supported by National Natural Science Foundation of China (No.31671145); Beijing Municipal Science & Technology Commission grant (Z141107002514016; D0906001000091; D101107047810005); Beijing Municipal Administration of Hospitals Clinical Medicine Development of special funding (XMLX201609; zy201409); Beijing Natural Science Foundation grant (No.7162087). Professor Wykes acknowledges the support of the NIHR Biomedical Research Centre at the South London and Maudsley NHS Foundation Trust and her NIHR Senior Investigator award. Declaration of Interests: We declare no competing interests. Ethics Approval Statement: All participants provided written informed consent, and the protocol was approved by the Beijing Huilongguan Hospital Ethics Committee (2006-3).

Impaired Visuospatial Short-Term Memory in Children with ADHD

ABSTRACTPrevious studies provide clear evidence that visuospatial memory performance in children with attention-deficit/hyperactivity disorder (ADHD) is significantly lower than in typically developing children. In the present study, we investigated a major cause of their low performance using a spatial span test. Possibly, inattention resulting from lack of motivation or interest causes their low performance so that they do not correctly encode targets to be remembered. On the other hand, a deficit in temporary maintenance per se may cause their low performance; that is, their inefficient use of rehearsal during a retention interval may lead to memory traces’ fast decay. Results in this study indicated that children with ADHD could sustain attention during the encoding phase. Furthermore, their performance at delayed recall was significantly lower than immediate recall, but delayed recall did not affect typically developing children's performance. These results provide evidence for the likelihood that a factor causing children with ADHD difficulty in temporarily maintaining visuospatial information is fast decay of memory traces as a result of inefficient use of rehearsal, not inattention in the encoding phase.

A Study of the Effects of Daily Physical Activity on Memory and Attention Capacities in College Students.

This study evaluated the relationship between daily physical activity (DPA) and memory capacity, as well as the association between daily activity and attention capacity, in college students in Taiwan. Participants (mean age = 20.79) wore wearable trackers for 106 days in order to collect DPA. These data were analyzed in association with their memory and attention capacities, as assessed using the spatial span test (SST) and the trail making test (TMT). The study showed significant negative correlations between memory capacity, time spent on the attention test (TSAT), calories burnt, and very active time duration (VATD) on the day before testing (r = −0.272, r = −0.176, r = 0.289, r = 0.254, resp.) and during the week prior to testing (r = −0.364, r = −0.395, r = 0.268, r = 0.241, resp.). The calories burnt and the VATD per day thresholds, which at best discriminated between normal-to-good and low attention capacity, were ≥2283 calories day−1, ≥20 minutes day−1 of very high activity (VHA) on the day before testing, or ≥13,640 calories week−1, ≥76 minutes week−1 of VHA during the week prior to testing. Findings indicated the short-term effects that VATD and calories burnt on the day before or during the week before testing significantly and negatively associated with memory and attention capacities of college students.

The Association between Obesity and Cognitive Function in Otherwise Healthy Premenopausal Arab Women.

Objective To examine the association between obesity and cognitive function in healthy premenopausal women. Methods From a cohort of 220 women, 98 were randomly selected that provided complete data. Body composition was examined by dual-energy X-ray scan. All participants completed the Cambridge Neuropsychological Test Automated Battery (CANTAB) to assess cognitive performance in three domains: attention, memory, and planning executive function. The Reaction Time (RTI) test was used to assess motor and mental response speeds; the Stockings of Cambridge (SOC) test was used to assess planning executive function. For memory assessment, the Delayed Match to Sample (DMS), Pattern Recognition Memory (PRM), and Spatial Span (SSP) tests were used to assess forced choice recognition memory, visual pattern recognition memory, and working memory capacity, respectively. Results 36 (36.7%) were morbidly obese, 22 (22.4%) obese, and 23 (23.5%) overweight. Performance on RTI and SOC planning ability were not associated with body mass index (BMI). DMS mean time to correct response, when stimulus is visible or immediately hidden (0 ms delay), was higher by 785 ± 302 ms (milliseconds) (p=0.011) and 587 ± 259 ms (p=0.026) in morbidly obese women compared to normal weight women. Memory span length was significantly lower in overweight (5.5 ± 1.3, p=0.008) and obese women (5.6 ± 1.6, p=0.007) compared to normal weight (6.7 ± 0.9). DEXA-assessed body fat (%) showed similar associations as BMI, and latency to correct response on DMS and PRM was positively correlated with percentage of body fat, but not with VO2 max. Conclusion In otherwise healthy premenopausal women, obesity did not impact accuracy on cognitive tasks related to attention, memory, or planning executive function, but morbid obesity was associated with higher latency to correct response on memory-specific tasks and lower memory span length.

Neurocognitive and physical functioning in the Seveso Women's Health Study

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is neurotoxic in animals but few studies have investigated its effects on the human brain. Related dioxin-like compounds have been linked to poorer cognitive and motor function in older adults, with effects more pronounced in women, perhaps due to the loss of neuro-protective estrogen in menopause. On 10 July 1976, a chemical explosion in Seveso, Italy, resulted in one of the highest known residential exposures to TCDD. In 1996, we initiated the Seveso Women's Health Study, a retrospective cohort study of the health of the women who were newborn to 40 years old in 1976. Here, we investigate whether TCDD exposure is associated with physical functioning and working memory more than 20 years later. Individual TCDD concentration (ppt) was measured in archived serum collected soon after the explosion. In 1996 and 2008, we measured physical functioning (n=154) and working memory (n=459), respectively. We examined associations between serum TCDD and motor and cognitive outcomes with multivariate linear regression and semi-parametric estimators. A 10-fold increase in serum TCDD was not associated with walking speed (adjusted β=0.0006ft/s, 95% Confidence Interval (CI): −0.13, 0.13), upper body mobility (adjusted β=−0.06, 95% CI: −0.36, 0.23), or manual dexterity (adjusted β=0.34, 95% CI: −0.65, 1.33). We observed an inverted U-shaped association in grip strength, with poorer strength in the lowest and highest TCDD exposure levels. There was no association between TCDD and the Wechsler digit and spatial span tests. Neither menopause status at assessment nor developmental timing of exposure modified associations between TCDD and working memory. Our findings, in one of the only studies of TCDD's effects on neuropsychological and physical functioning in women, do not indicate an adverse effect on these domains, with the exception of a U-shaped relationship with grip strength. Given the limited assessment and relative youth of the women at this follow-up, future work examining additional neuropsychological outcomes is warranted.

Sex differences of hippocampal structure in bipolar disorder

Although differential patterns in clinical characteristics have been consistently noted between male and female patients with bipolar disorder (BD), the effect of sex on the hippocampal structure remains unclear. To address this, the present study investigated the effects of BD and sex on the hippocampal structure, and the relationship between the hippocampal structure and cognitive performance. Morphometric and neurocognitive analyses were performed in 91 subjects (patients with BD: male/female = 33/19; normal controls: male/female = 22/17). Patients had significantly decreased left parahippocampal gyrus area and left/right hippocampal volume compared to normal controls. Within the BD group only, female patients presented with smaller right hippocampal volume than males. In the Spatial Span (SS) test (used to assess working memory capacity) and the Maze test (used to evaluate the ability to anticipate), patients demonstrated decreased performance compared to normal controls, with a significant main effect of sex. Left parahippocampal gyrus area and right hippocampal volume were positively correlated with SS and Maze in patients; moreover, right hippocampal volume predicted 17.4% of SS performance variance. These results suggest that there may be a difference between male and female patients with regard to right hippocampal volume, and that female patients may need more attention than males.

Phonological awareness and spatial visual memory among sample of dyslexic children

This study aims to identify the relationship between phonological awareness and spatial visual memory, as well as, to detect the differences between Kuwaiti males and females and non-Kuwaitis with regard to reading learning difficulties in certain variables. The study adopts a comparative descriptive approach and uses sample of 350 primary students (3-5 grades) with reading learning difficulties (200 males and 150 females) Kuwaitis and non-Kuwaitis. Their ages ranged between 8- 10 years. Phonological awareness test and spatial visual memory test are applied. The findings of the study show that there is a statistically significant positive correlation between the components of phonological awareness tests (syllable &amp; phoneme deletion test and non-word reading accuracy test) and between spatial visual memory tests (Forward Spatial Span Test and Backward Spatial Span Test) from males and females sample. There are no significant differences between males and females in phonological awareness skills (phoneme deletion test, and non-word reading accuracy test). Females show better performance than males in spatial visual memory tasks (Forward Spatial Span Test and Backward Spatial Span Test). Non-Kuwaitis show better performance than Kuwaitis in phonological awareness skills (syllable &amp; phoneme deletion, and non-word reading accuracy test) and in spatial visual memory tasks (Forward Spatial Span Test and Backward Spatial Span Test). The results of the regression suggested that the integration of sounds is the only test that can predict reading disabilities. As (syllable &amp; phoneme deletion, and t non-word reading accuracy test) are the most predictable of spatial visual memory.

Phonological awareness and spatial visual memory among sample of dyslexic children

This study aims to identify the relationship between phonological awareness and spatial visual memory, as well as, to detect the differences between Kuwaiti males and females and non-Kuwaitis with regard to reading learning difficulties in certain variables. The study adopts a comparative descriptive approach and uses sample of 350 primary students (3-5 grades) with reading learning difficulties (200 males and 150 females) Kuwaitis and non-Kuwaitis. Their ages ranged between 8- 10 years. Phonological awareness test and spatial visual memory test are applied. The findings of the study show that there is a statistically significant positive correlation between the components of phonological awareness tests (syllable &amp; phoneme deletion test and non-word reading accuracy test) and between spatial visual memory tests (Forward Spatial Span Test and Backward Spatial Span Test) from males and females sample. There are no significant differences between males and females in phonological awareness skills (phoneme deletion test, and non-word reading accuracy test). Females show better performance than males in spatial visual memory tasks (Forward Spatial Span Test and Backward Spatial Span Test). Non-Kuwaitis show better performance than Kuwaitis in phonological awareness skills (syllable &amp; phoneme deletion, and non-word reading accuracy test) and in spatial visual memory tasks (Forward Spatial Span Test and Backward Spatial Span Test). The results of the regression suggested that the integration of sounds is the only test that can predict reading disabilities. As (syllable &amp; phoneme deletion, and t non-word reading accuracy test) are the most predictable of spatial visual memory.

Age-related similarities and differences in monitoring spatial cognition

ABSTRACTSpatial cognitive performance is impaired in later adulthood but it is unclear whether the metacognitive processes involved in monitoring spatial cognitive performance are also compromised. Inaccurate monitoring could affect whether people choose to engage in tasks that require spatial thinking and also the strategies they use in spatial domains such as navigation. The current experiment examined potential age differences in monitoring spatial cognitive performance in a variety of spatial domains including visual–spatial working memory, spatial orientation, spatial visualization, navigation, and place learning. Younger and older adults completed a 2D mental rotation test, 3D mental rotation test, paper folding test, spatial memory span test, two virtual navigation tasks, and a cognitive mapping test. Participants also made metacognitive judgments of performance (confidence judgments, judgments of learning, or navigation time estimates) on each trial for all spatial tasks. Preference for allocentric or egocentric navigation strategies was also measured. Overall, performance was poorer and confidence in performance was lower for older adults than younger adults. In most spatial domains, the absolute and relative accuracy of metacognitive judgments was equivalent for both age groups. However, age differences in monitoring accuracy (specifically relative accuracy) emerged in spatial tasks involving navigation. Confidence in navigating for a target location also mediated age differences in allocentric navigation strategy use. These findings suggest that with the possible exception of navigation monitoring, spatial cognition may be spared from age-related decline even though spatial cognition itself is impaired in older age.

The Effect of Visuospatial Rehabilitation on the Visuospatial Function and Attention in Patients with Schizophrenia

본 연구는 시공간 재활훈련이 조현병 환자들의 시공간 기능을 포함한 인지기능의 향상과 사회적 기능, 조현병 증상의 완화에 효과적인가를 알아보고자 하였다. 연구대상은 서울 소재 사회복귀시설에 거주하고 있는 조현병 환자 43명으로, 이들은 재활집단(n=14), 비교집단(n=14), 통제집단(n=15)으로 무선할당되었다. 재활집단은 주 3회 각 40분씩 6주에 걸쳐 총 18회기의 시공간 재활훈련을, 비교집단은 동일한 회기 동안 테트리스 게임을 실시하였고, 통제집단은 아무런 처지도 받지 않았다. 시공간 재활훈련 프로그램은 Bracy (1994)가 개발한 PSS CogReHab을 국내 상황에 맞게 수정하여 개발한 인지재활 프로그램을 사용하였다. 시공간 기능/시각기억, 주의, 언어기억, 작업기억, 집행기능을 평가하는 신경심리검사와 조현병 증상을 측정하는 Positive and Negative syndrome Scale (PANSS), 사회적 기능을 평가하는 한국판 정신사회적 기능-증상 평가척도(BASIS-32) 설문지를 재활훈련 전과 후에 실시하였다. 그 결과, 재활 후 실시한 신경심리검사에서 재활집단은 비교집단과 통제집단과 다르게 Rey 도형검사 모사단계, 숫자외우기 검사의 바로 따라외우기 조건, Stroop 검사의 단어-색채 조건의 수행이 유의하게 증가하였다. 그리고 재활집단에서 PANSS로 측정한 음성증상이 완화된 것이 관찰되었다. 이러한 결과는 시공간기능 재활이 조현병 환자의 시공간 기능 및 주의 기능 향상, 음성증상 완화에 효과적이라는 것을 의미하며, 조현병 환자의 치료에 시공간 기능을 포함하는 인지재활의 필요성을 시사한다.

Serum dioxin levels and neuropsychological functioning in the Seveso Women’s Health Study

INTRODUCTION: 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is neurotoxic in animals but few studies have investigated its effects on the human brain. Related dioxin-like compounds have been linked to poorer cognitive function in adults, with effects more pronounced in women, perhaps due to the loss of neuro-protective estrogen in menopause. METHODS: In 2008, we measured working memory (n=459) via the Wechsler Memory Scale digit span and spatial span tests in the Seveso Women’s Health Study (SWHS), a historical cohort of women residing near Seveso, Italy in 1976, at the time of an industrial explosion which resulted in the highest known population exposure to TCDD. SWHS comprises 981 women who were 0 to 40 years in 1976, resided in the most contaminated areas, and had TCDD concentration measured in archived sera collected soon after the explosion. The associations between 1976 serum TCDD and memory scale scores were modeled with multivariate linear regression and targeted maximum likelihood estimation (tmle). RESULTS: In the 2008 study sample, the geometric mean of 1976 serum TCDD levels was 68.1 (95% confidence interval: 59.8, 77.5) ppt, lipid-adjusted. The average age was 52.3(±11.3) years, with 53% post-menopause in 2008. The proportion of women scoring below the age-scaled median on the digit span (7) and spatial span (8) tests was 44% and 41%, respectively. Adjusting for a priori confounders, a 10-fold increase in TCDD was not associated with performance on the digit span test [β=0.25 (95%CI -0.19, 0.69)], spatial span test (β=0.02 (95%CI -0.44, 0.48), nor their forward and backward components. We did not observe effect modification by menopause status in 2008. DISCUSSION: This is the first study of the exclusive effects of TCDD on cognition in women, particularly surrounding menopause. Our findings do not indicate an adverse effect of dioxin exposure on working memory function in adult women in Italy.

The Effects of Repeat Testing, Malingering, and Traumatic Brain Injury on Computerized Measures of Visuospatial Memory Span.

Spatial span tests (SSTs) such as the Corsi Block Test (CBT) and the SST of the Wechsler Memory Scale are widely used to assess deficits in spatial working memory. We conducted three experiments to evaluate the test–retest reliability and clinical sensitivity of a new computerized spatial span test (C-SST) that incorporates psychophysical methods to improve the precision of spatial span measurement. In Experiment 1, we analyzed C-SST test–retest reliability in 49 participants who underwent three test sessions at weekly intervals. Intraclass correlation coefficients (ICC) were higher for a psychophysically derived mean span (MnS) metric (0.83) than for the maximal span and total correct metrics used in traditional spatial-span tests. Response times (ReTs) also showed high ICCs (0.93) that correlated negatively with MnS scores and correlated positively with response-time latencies from other tests of processing speed. Learning effects were insignificant. Experiment 2 examined the performance of Experiment 1 participants when instructed to feign symptoms of traumatic brain injury (TBI): 57% showed abnormal MnS z-scores. A MnS z-score cutoff of 3.0 correctly classified 36% of simulated malingerers and 91% of the subgroup of 11 control participants with abnormal spans. Malingerers also made more substitution errors than control participants with abnormal spans (sensitivity = 43%, specificity = 91%). In addition, malingerers showed no evidence of ReT slowing, in contrast to significant abnormalities seen on other malingered tests of processing speed. As a result, differences between ReT z-scores and z-scores on other processing speed tests showed very high sensitivity and specificity in distinguishing malingering and control participants with either normal or abnormal spans. Experiment 3 examined C-SST performance in a group of patients with predominantly mild TBI: neither MnS nor ReT z-scores showed significant group-level abnormalities. The C-SST improves the reliability and sensitivity of spatial span testing, can accurately detect malingering, and shows that visuospatial working memory is largely preserved in patients with predominantly mild TBI.