How does environmental knowledge allow us to come back home?

Herein, we investigate how the three types of mental spatial representation (landmark, route and survey) are reorganized to perform wayfinding and homing behaviour. We also investigate the contribution of visuo-spatial working memory in reaching and in vista space in performing the retracing of the path. For this purpose, we asked 68 healthy college students to learn and come back along an unknown path in a real environment and to perform two different forward and backward working memory tasks, one in the reaching space (Corsi Block-Tapping Test) and the other in a vista space (Walking Corsi Test). The results show that participants performed better when travelling the route forward (which corresponds to the originally learned direction) than when travelling the route backward (return path) and that working memory in vista space is crucial for both wayfinding and homing behaviour, while the working memory for reaching space contributes only to homing behaviour. Although homing behaviour is an early mechanism in navigation shared among many species, it represents a very complex behaviour that requires both topographic and visuo-spatial memory as well as the first two levels of environmental knowledge.

Complexity of Frontal Cortex fNIRS Can Support Alzheimer Disease Diagnosis in Memory and Visuo-Spatial Tests.

Decline in visuo-spatial skills and memory failures are considered symptoms of Alzheimer's Disease (AD) and they can be assessed at early stages employing clinical tests. However, performance in a single test is generally not indicative of AD. Functional neuroimaging, such as functional Near Infrared Spectroscopy (fNIRS), may be employed during these tests in an ecological setting to support diagnosis. Indeed, neuroimaging should not alter clinical practice allowing free doctor-patient interaction. However, block-designed paradigms, necessary for standard functional neuroimaging analysis, require tests adaptation. Novel signal analysis procedures (e.g., signal complexity evaluation) may be useful to establish brain signals differences without altering experimental conditions. In this study, we estimated fNIRS complexity (through Sample Entropy metric) in frontal cortex of early AD and controls during three tests that assess visuo-spatial and short-term-memory abilities (Clock Drawing Test, Digit Span Test, Corsi Block Tapping Test). A channel-based analysis of fNIRS complexity during the tests revealed AD-induced changes. Importantly, a multivariate analysis of fNIRS complexity provided good specificity and sensitivity to AD. This outcome was compared to cognitive tests performances that were predictive of AD in only one test. Our results demonstrated the capabilities of fNIRS and complexity metric to support early AD diagnosis.

Cerebral Haemodynamic Changes in Type 2 Diabetes Mellitus Following a Three-Month Yoga Intervention: A Randomized Controlled Trial.

Background and purpose Cerebral haemodynamics and cognitive performance may be adversely affected in type 2 diabetes mellitus (T2DM). Previous studies reported reduced cerebral blood flow (CBF) and altered cerebrovascular reactivity (CVR) in T2DM. Yoga, an ancient holistic health approach, is known to be beneficial for T2DM. We hypothesized that yoga practice may alter CBF and the flow resistance in the middle cerebral artery (MCA) and improve cognition in T2DM. Our secondary objective was to explore the relationship between changes in cerebral haemodynamics and cognition in T2DM. Materials and methods Participants were randomly allotted into the yoga and control groups based on the eligibility criteria. One hour of yoga intervention specific to type 2 diabetes was provided to the yoga group for three months, while conventional treatment was provided to the control group. A transcranial Doppler was used to evaluate longitudinal changes in cerebral haemodynamics in MCA. A Corsi block tapping test was used to assess visio-spatial working memory. Results There were 75 participants recruited, of whom 38 participated in yoga and 37 participated in a control group. Both intention to treat and per protocol analysis showed significant results. At day 90, intention-to-treat analysis showed significant changes in CBF velocities (mean difference -10.85%, 95% CI (-13.26, -6.15), p<0.001), cerebral vasodilatory reserve (mean difference -0.23%, 95% CI (-0.43, -0.03), p=0.02) and cognition (mean difference -12.13%, 95% CI (-17.48, -6.78), p≤0.001). There was no between-group effect. Also, the correlation between the CBF and cognition did not show any significant results. Conclusion The three-month yoga intervention was associated with an improvement in cerebral hemodynamics. The study also revealed an improvement in visio-spatial working memory among patients with T2DM. The study did not show any correlation between the improvement in cerebral haemodynamics and working memory. We recommend larger and longer studies on yoga intervention for T2DM patients to evaluate whether such benefits are sustained and improve their quality of life.

Forward and backward spatial recall in Parkinson's disease and matched controls: A 1-year follow-up study.

Patients with Parkinson's disease (PD) exhibit a domain-general visuospatial dysfunction; however, no previous study has examined changes over time in forward and backward spatial recall in PD against controls. To evaluate changes in short-term (STM) and working memory (WM) dysfunction in PD, the current study assessed performance on a computer-modified version of the Corsi Block-Tapping Test (forward and backward recall) at two-time points 1 year apart, while simultaneously exploring associations with potentially relevant demographic and clinical variables. We enrolled 38 patients with PD and 38 controls matched for age, sex, and Montreal Cognitive Assessment (MoCA) total scores. Linear mixed-effects models analyzed the primary measured variables (forward and backward scores). At baseline, the dysfunction effect sizes were as follows: forward recall (-0.45, 95% CI [-0.90, 0.01]) and backward recall (-0.26, 95% CI [-0.71, 0.19]). At follow-up, patients exhibited substantially greater difficulties in backward recall (-0.65, 95% CI [-1.18, -0.13]) compared to the baseline assessment, whereas the forward dysfunction effect size remained almost the same (-0.43, 95% CI [-0.94, 0.09]). Age (p = .005, f = 0.35) and total scores on MoCA (p = .017, f = 0.18), irrespective of group and recall condition, were significant predictors of spatial block scores. The pattern of dysfunction effect sizes indicates that, in contrast to forward recall, backward recall dysfunction in PD worsened 1-year after the baseline assessment, presumably reflecting the progression of PD-related visuospatial WM dysfunction.

Spatial Olfactory Memory and Spatial Olfactory Navigation, Assessed with a Variant of Corsi Test, Is Modulated by Gender and Sporty Activity.

Many studies have focused on navigation, spatial skills, and the olfactory system in comparative models, including those concerning the relationship between them and physical activity. Although the results are often in contrast with each other, it is assumed that physical activity can affect cognition in different ways-both indirectly and through a certain influence on some brain structures. In contrast, there is little research that focuses on the relationship between spatial abilities and olfactory abilities in humans. This research aimed to evaluate and compare the performance in working memory tasks of athletes and non-athletes who require good visual-spatial navigation, olfactory-spatial navigation, and olfactory-semantic skills. The study involved 236 participants (83 athletes) between the ages of 18 and 40. All subjects were matched by age or sex. The standard Corsi Block Tapping Test (CBTT) was administrated to investigate the visual-spatial memory. Olfactory-spatial navigation and olfactory-semantic skills were assessed with two modified versions of CBTT: Olfactory CBTT (OCBTT) and Semantic-Olfactory CBTT (SOCBTT) respectively. The results show differences between the CORSI conditions in direction of a poor performance for athletes. A gender effect in favor of men was also found, particularly in the classic version of the CBTT. Both groups performed better in the classic version of the CBTT than OCBTT and SOCBTT. The mean of SOCBTT results is markedly lower, perhaps due to the different information processing systems needed to perform this kind of task. It is possible to explain how sports practice can affect tasks that require spatial skills and olfactory perception differently, thus supporting new hypotheses and opening new scientific horizons.

Effects of a Coordinative Ability Training Program on Adolescents' Cognitive Functioning.

The purpose of this randomized controlled study was to investigate the effects of a 12-week coordinative ability training program on adolescents' cognitive functioning, using evaluation tests of visuospatial perception, attention, and working memory. We randomly assigned 60 public school students (14-15 years) to either an experimental coordinative abilities training (∼40 min twice/week) group (n = 30) or a control group (n = 30) who received general psycho-physical wellness training (∼40 min., twice a week). At baseline and after training we used two standardized motor tests and a single cognitive measure (Corsi's Block-tapping test) to assess students' visuospatial perception, attention, and working memory. We found a significant Time x Group interaction for the Throwing and Catching Test and Corsi's Block-Tapping test, reflecting a meaningful experimental group improvement (p < 0.001), and there were no significant pre-post changes found in the control group. Thus, a 12-week program of coordinative abilities was able to improve not only coordination skills but aspects of cognitive functioning relevant to academic achievement.

Are ventrolateral and dorsolateral prefrontal cortices involved in the computerized Corsi block-tapping test execution? An fNIRS study.

The Corsi block-tapping test (CBT) is an old neuropsychological test that, requiring the storage and the reproduction of spatial locations, assesses spatial working memory (WM). Despite its wide use in clinical practice, the specific contribution of prefrontal cortex (PFC) subregions during CBT execution has not been clarified yet. Considering the importance of spatial WM in daily life and the well-known role of ventrolateral-PFC/dorsolateral-PFC (VLPFC/DLPFC) in WM processes, the present study was aimed at investigating, by a 20-channel functional near-infrared spectroscopy (fNIRS) system (including four short-separation channels), the hemodynamic response of the VLPFC/DLPFC during a computerized version of the CBT. Thirty-nine university students were asked to perform CBT standard version (CBTs), block-suppression CBT (CBTb), and control task (CBTc). A VLPFC activation during CBTs and a DLPFC activation during CBTb were hypothesized. The results of the Bayesian analysis have not shown a delineated specific activation of VLPFC/DLPFC during either CBTs or CBTb. These results together with the related ones obtained by others using fMRI are not sufficient to definitively state the role of the PFC subregions during CBT execution. The adoption of high-density diffuse optical tomography would be helpful in further exploration of the PFC involvement in spatial WM tasks.

A selective egocentric topographical working memory deficit in the early stages of Alzheimer's disease: a preliminary study.

The aim of this study was to determine whether an egocentric topographical working memory (WM) deficit is present in the early stages of Alzheimer's disease (AD) with respect to other forms of visuospatial WM. Further, we would investigate whether this deficit could be present in patients having AD without topographical disorientation (TD) signs in everyday life assessed through an informal interview to caregivers. Seven patients with AD and 20 healthy participants performed the Walking Corsi Test and the Corsi Block-Tapping Test. The former test requires memorizing a sequence of places by following a path and the latter is a well-known visuospatial memory task. Patients with AD also performed a verbal WM test to exclude the presence of general WM impairments. Preliminary results suggest that egocentric topographical WM is selectively impaired, with respect to visuospatial and verbal WM, even without TD suggesting an important role of this memory in the early stages of AD.

Neuropsychological functioning in young subjects with generalized anxiety disorder with and without pharmacotherapy.

The purpose of this study was to investigate the neuropsychological functioning and the effect of antidepressant drug intake on cognitive performance in a group of relatively young generalized anxiety disorder (GAD) patients. Forty patients with a DSM-IV diagnosis of GAD and 31 healthy subjects participated in the study (Control group, CON). None of the selected subjects had comorbid depression. GAD subjects were divided into two different subgroups: 18 were taking antidepressants [GAD-pharmacotherapy (GAD-p group)] and 22 were treatment-naïve (GAD group). Each group was administered with a comprehensive neuropsychological battery to assess attention, memory and executive functions. Performance on executive and non-verbal memory tasks of both GAD groups was largely worse than the CON group. However, these deficits seem to be more marked in patients taking antidepressants, especially in the domains of attention, non-verbal memory and executive functions. The present study indicates that GAD is associated with cognitive impairments among young adults. However, the observed association of neuropsychological deficits and the use of pharmacotherapy suggest a possible effect of antidepressant treatment on attention, executive functioning and non-verbal memory.

Spatial working memory in Alzheimer's disease: A study using the Corsi block-tapping test.

The Corsi block-tapping test was developed as a non-verbal task to measure spatial memory. In this test, cubes are tapped by the examiner in novel sequences of increasing length after which participants are required to reproduce each sequence immediately. OBJECTIVES: To evaluate spatial working memory in Alzheimer's disease (AD) patients. METHODS: 30 elderly control subjects (21 women, 9 men) and 30 patients with probable Alzheimer's disease (15 women and 15 men), with 8 or more years of schooling, were evaluated with the Mini-Mental State Examination (MMSE), digit span and Corsi block-tapping test. Proportions were compared using Chi-Square, and continuous variables with the Mann-Whitney tests. RESULTS: AD patients were older than controls (p=0.014), but there were no differences regarding gender or educational level between these groups. The performance on the Corsi block-tapping test differed between AD and control individuals (p=0.010), and between patients with moderate dementia and controls (p=0.032), but not between control individuals and patients with mild dementia (p=0.090). CONCLUSIONS: In the present study, AD patients with moderate dementia showed impairment in spatial working memory while those with mild dementia did not. This finding may be due to the relatively small sample size, but it is also possible that spatial memory may be normal in the initial (limbic) phase of AD.

O teste dos blocos de Corsi (TBC) foi desenvolvido como uma medida não verbal da memória operacional espacial (MOE). Os blocos devem ser tocados pelo examinador em seqüências crescentes e os participantes devem repetir cada seqüência. OBJETIVOS: Avaliar a MOE em pacientes com DA. MÉTODOS: 30 sujeitos controles (21 mulheres, 9 homens) e 30 pacientes com DA provável (15 mulheres, 15 homens) com escolaridade superior a 8 anos foram avaliados através do Mini Exame do Estado Mental (MEEM), extensão de dígitos, fluência verbal e TBC. Os dados foram comparados através do teste do qui-quadrado e as variáveis contínuas através do teste de Mann-Whitney. RESULTADOS: Pacientes com DA eram mais velhos (p=0,014), mas não houve diferença quanto ao gênero ou escolaridade. O desempenho no teste dos blocos de Corsi foi diferente entre os pacientes com DA e sujeitos controles (p=0,010) e entre pacientes com demência de intensidade moderada e controles (p=0,032), mas não houve diferença entre pacientes com DA leve e controles (p=0,090). CONCLUSÕES: No presente estudo, pacientes com DA moderada demonstraram comprometimento na memória operacional espacial, o que não foi demonstrado nos pacientes com demência leve. Este achado pode estar relacionado ao pequeno tamanho da amostra, mas também é possível que a memória operacional espacial esteja normal na fase inicial (límbica) da DA.