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espanolPara evaluar los efectos del cafe cafeinado (150mg/130 ml) en la memoria inmediata y en la planificacion visomotora en estudiantes universitarios, se utilizo una muestra de 109 estudiantes, de los cuales 54 conformaban el grupo de cafe descafeinado (control) y 55, el de cafe cafeinado. El diseno fue experimental pretest-postest, con grupo control. Se evaluo la memoria inmediata, los aciertos, los errores de secuenciacion, de atravesamientos y totales, asi como la velocidad y la precision mediante una prueba de planificacion visomotora (TESEN). Luego, aleatoriamente y mediante el metodo doble-ciego, se les dio a beber a los participantes 130ml de cafe sin cafeina/con cafeina, (grupo control y experimental, respectivamente); despues de 30 minutos, se evaluaron los mismos indices con diferentes pruebas. Los datos se analizaron mediante ANOVA de medidas repetidas, con un alpha= 0.05. El cafe cafeinado (150mg/130 ml) incremento la memoria inmediata y disminuyo los errores de atravesamiento, lo que muestra leves efectos ergogenicos del cafe con cafeina en los estudiantes de ambos sexos. EnglishTo evaluate the effects of caffeinated coffee (150mg/130 ml) on immediate memory and visuomotor planning in university students, an experimental design pretest-posttest with a control group was used. The sample was constituted by 109 students -54 belonged to the decaffeinated coffee group (control) and 55 to the caffeinated coffee group-. Immediate memory, successes, sequencing, traversing and total mistakes, as well as speed and accuracy were evaluated by a test of visuomotor planning (TESEN). Then, randomly and using the double-blind method, participants drank 130ml of coffee without caffeine/with caffeine (control and experimental group, respectively). After 30 minutes, the same indexes were evaluated with different tests. Data were analyzed by repeated measures ANOVA with an alpha = 0.05. Caffeinated coffee (150mg / 130ml) increased immediate memory and decreased traversing mistakes, showing its light ergogenic effects on students of both sexes.

Objective An intriguing electrophysiological feature of patients with Huntington’s disease (HD) is the delayed latency and decreased amplitude of somatosensory long-latency evoked potentials (LLeps). We investigated whether such dysfunction was associated with delayed conscious perception of the sensory stimulus. Methods Sixteen HD patients and 16 control subjects faced a computer screen showing the Libet’s clock ( Libet et al., 1983 ). In Rest trials, subjects had to memorize the position of the clock handle at perception of either electrical or thermal stimuli (AW). In React, additionally, they were asked to make a fist with their right hand, in a simple reaction time task (SRT). LLseps were recorded from Cz in both conditions. Results LLeps negative peak latency (N2) and SRT were abnormally delayed in patients in all conditions. AW was only abnormally prolonged in the React condition but the time difference between AW and the negative peak of the LLeps was not different in the two groups. There was a significant negative correlation between SRT and AW or LLeps amplitude in patients but not in healthy subjects. Conclusion Our HD patients did not show abnormalities in conscious perception of sensory stimuli but their LLeps abnormalities were more marked when they had to react. This is compatible with failure to detect stimulus salience rather than with a cognitive defect. Significance HD patients at early stages of the disease have preserved subjective perception of sensation but faulty sensorimotor integration.

A cognitive stimulating lifestyle has been observed to confer cognitive benefits in multiple neurodegenerative diseases. However, the underlying neurobiological basis of this phenomenon remains unclear. Huntington's disease can provide a suitable model to study the effects and neural mechanisms of cognitive engagement in neurodegeneration. In this study, we investigate the effect of lifestyle factors such as education, occupation and engagement in cognitive activities in Huntington's disease gene carriers on cognitive performance and age of onset as well as the underlying neural changes sustaining these effects, measured by magnetic resonance imaging. Specifically, we analyzed both gray matter volume and the strength of connectivity of the executive control resting-state network. High levels of cognitive engagement were significantly associated with more preserved executive functions, a delay in the appearance of symptoms, reduced volume loss of the left precuneus and the bilateral caudate and a modulation of connectivity strength of anterior cingulate cortex and left angular gyrus with the executive control network. These findings suggest that a cognitively stimulating lifestyle may promote brain maintenance by modulating the executive control resting-state network and conferring protection against neurodegeneration, which results in a delayed onset of symptoms and improved performance in executive functions.

A prospective, observational multicenter study was carried out assessing neuropsychiatric symptoms in a sample of 117 subjects in order to validate the Spanish version of the Problem Behaviors Assessment-Short (PBA-s). The psychometric properties of this version were analyzed. Inter- and intra-rater reliability were good: the mean weighted Cohen’s kappa was 0.90 for severity scores and 0.93 for frequency scores. Four factors accounting for 56% of the total variance were identified after an exploratory factor analysis: apathy, irritability, depression, and perseveration. The PBA-s correlates strongly with the Neuropsychiatric Inventory, demonstrating its accuracy for assessing neuropsychiatric symptoms in patients with Huntington’s disease.

We investigated the influence of color on the identification of both non-studied and studied objects. Participants studied black and white and color photos of common objects and memory was assessed with an identification test. Consistent with our meta-analysis of prior research, we found that objects were easier to identify from color than from black and white photos. We also found substantial priming in all conditions, and study-to-test changes in an object's color reduced the magnitude of priming. Color-specific priming effects were large for color-complex objects, but minimal for color-simple objects. The pattern and magnitude of priming effects was not influenced either by the extent to which an object always appears in the same color (i.e., whether a color is symptomatic of an object) or by the object's origin (natural versus fabricated). We discuss the implications of our findings for theoretical accounts of object perception and repetition priming.

En este trabajo se evaluó el papel que juega la cafeína (150mg/kg) en el aprendizaje espacial (adquisición y retención) en ratones mediante las mediciones de la latencia de salida, velocidad, aciertos, regresos, errores y excretas en un laberinto de 3 x 3 metros. Los sujetos fueron moldeados para una ruta en el laberinto y luego se aleatorizaron 20 machos y 20 hembras para la administración de cafeína (s.c.) y solución salina durante ocho días consecutivos; luego se observó la retención de este aprendizaje y se moldeó otra ruta para evaluar su retención 24 horas después: La cafeína incrementó la retención del aprendizaje 1, donde hubo los mayores aciertos, y en el segundo las hembras con cafeína exhibieron mayor velocidad y aciertos mientras que los machos, presentaron menores aciertos y velocidad que todos los grupos; como vemos, en el segundo caso, la cafeína fortaleció la retención del aprendizaje 2 en las hembras y la debilitó en los machos. Se concluye que la cafeína (150mg/kg) influyó positivamente en la retención del aprendizaje espacial, mas no en la adquisición. Este artículo está asociado a la línea de investigación en Cafeína y Cognición de la Universidad de la Sabana.

El objetivo de la presente revisión es analizar varios factores relacionados con la cafeína, sus efectos sobre determinados aspectos de la salud y de los procesos cognoscitivos. La cafeína es una sustancia ergogénica, que interactúa principalmente con esta sustancia, la adenosina, con sus diferentes subtipos de receptores y las acciones diversas que median cada uno de éstos, así como la distribución de estos receptores en el organismo; se destacaron algunos de los efectos positivos y negativos sobre la salud. Se examinan los aspectos neurobioquímicos de la cafeína, su relación con algunas patologías como el cáncer, el Parkinson y el Alzheimer. Adicionalmente se revisaron los efectos de la cafeína sobre la atención, base fundamental de otros procesos cognoscitivos más complejos como el aprendizaje, la memoria, el lenguaje y el pensamiento, y teniendo en cuenta la alta incidencia del déficit atencional con y sin hiperactividad, se presentan algunas investigaciones relacionadas con esta problemática, sus síntomas, formas de evaluación y de tratamiento, en las que se involucraran a la familia y los profesores.

Objective In Parkinson's disease (PD), effects on behavior and cognition of levodopa/carbidopa intestinal gel (LCIG) and subthalamic stimulation (STN-DBS) and their practical consequences remain controversial. This study was designed to analyze the possible effects of these therapies on cognition and behavior after 1 year follow-up. Methods This was an open-label, nonrandomized prospective study for pre- and postintervention analyses. Twenty-four patients were considered eligible to be candidates for complex therapies such as STN-DBS or LCIG; 23 patients treated with standard medication were included as controls. Several cognitive, behavioral, and motor scales were administered before and at 6 and 12 months after the intervention. Results Patients treated with LCIG experienced significant improvement in specific neuropsychological functions when compared with patients receiving STN-DBS and conventional medical treatment after 1 year from the onset of the intervention. In this study, no significant cognitive or behavioral changes occurred in patients treated with subthalamic stimulation when compared to patients receiving conventional medical treatment at 1 year follow-up. Conclusions Patients treated with LCIG may significantly improve some specific neuropsychological functions when compared with patients receiving STN-DBS and with patients receiving conventional medical treatment after 1 year from the intervention; there are not significant cognitive or behavioral changes in patients treated with STN-DBS when compared to PD patients receiving conventional medical treatment after 1 year from the intervention. The outcomes showed in the study can help to the selection of the appropriate candidates for STN-DBS and LCIG.

Background: Basic issues regarding factors influencing progressive supranuclear palsy (PSP) patient caregiver burden remain unresolved, including whether and how disease severity and duration influence caregiver burden. Objective: To examine the relation between PSP patient caregiver burden and disease severity, describe the time course of caregiver burden in relation to disease progression, and identify the contribution of other factors (e.g., patient memory and behavioral problems, caregiver gender) to caregiver burden. Methods: Mail survey of 180 caregivers of PSP patients (living at home and cared for by nonprofessionals) who were members of the Society for Progressive Supranuclear Palsy. The survey included the Burden Interview, an instrument measuring caregiver burden by inquiring how they feel about different aspects and demands of caregiving. Results: Caregiver burden was related to both PSP disease severity ( r = 0.40) and disability/need for assistance ( r = 0.43). The relation between burden and disease duration was nonlinear, following the same time course as disease severity; the burden increased during the first 18 months postdiagnosis and leveled off thereafter. Women reported more burden than men (caregiver sex Δ r 2 = 0.05), even after controlling for disease severity and duration (Δ r 2 = 0.22) and patient gender (Δ r 2 r 2 = 0.09), and aggressiveness (Δ r 2 = 0.02). Conclusion: Burden in PSP is related to disease severity, disease duration, and caregiver gender (even after controlling for patient9s memory, patient depression, and aggression).

Many studies have demonstrated a strong association between the presence of one or two epsilon 4 alleles and Alzheimer's disease (AD), although few data are available on the apolipoprotein E (APOE) epsilon 4 frequencies at the preclinical stages of AD. Thus, with a view to determining whether APOE genotyping could be useful in the early detection of AD, we determined the Apoe allele frequencies in patients with memory complaints without dementia (age-related memory decline, ARMD). We found an APOE epsilon 4 allele frequency of 0.315 in the ARMD group, similar to 0.293 in the AD group, in contrast to 0.057 in the control group. Significant differences (t=-2.91, df=25, p=0.008) were found between the Alzheimer's Disease Assessment Scale (ADAS) total scores in the ARMD patients with at least one epsilon 4 allele (mean=24.2) compared with the ARMD patients without the epsilon 4 allele (mean=14.7). Our results suggest that the patients with memory complaints, a high ADAS score, and the presence of one or two APOE-4 alleles could be at high risk for developing AD. Thus, we propose that genotyping in conjunction with the ADAS scale may prove useful as diagnostic markers of AD in the presymptomatic stages.

Background Although age of onset of Huntington’s disease (HD) is mainly determined by the size of the CAG repeat expansion, other factors may play a role. One potential factor is Cognitive Reserve (CR), as it has been shown in other neurodegenerative disorders and ageing. Objective The objective of this study is to investigate the effect of CR on age of onset in HD and to examine the neural bases underlying the individual differences in executive function that could be due to the effects of CR in HD. Methods Thirty-one HD patients completed a CR questionnaire and were scanned using functional magnetic resonance imaging. We analysed the Resting State Executive Control Network (RS-ECN), a novel approach to study the brain areas underlying executive function. The strength of connectivity with this network was calculated voxel-wise. The difference between the theoeretical and estimated age of onset (26 symptomatic-HD) was calculated for each patient. Results Our results revealed that high levels of CR significantly delayed the appearance of clinical symptoms. Functional connectivity and morphometry analysis showed a brain reorganisation modulated by CR, which changed the connectivity strength in the anterior cingulate cortex, in the left superior parietal cortex (SPC) and slowed the volume loss in the bilateral precuneus and the bilateral caudate. Furthermore, higher strength of connectivity in the left SPC was related to better performance in cognitive flexibility (TMT B-A) and working memory (Backward Digits Span) tasks. Conclusions These findings provide converging evidence that CR might act as a protective mechanism for the progression of the disease, delaying the onset of symptoms and improving the performance in executive functions by modulating the RS-ECN and slowing brain atrophy.

Introduction Huntington’s disease (HD) is a neurodegenerative disorder that induces striatal and cortical neuronal dysfunction and loss which main symptom is motor impairment. Goals to study whether this motor impairment is accompanied by changes in brain activity and functional connectivity. Methods Fifteen early stage HD patients with a UHDRS motor score > 5 (9 men, mean age = 48 ± 8.9, mean TFC = 11.7 ± 1.17) and 15 controls (9 men, mean age = 46.6 ± 8.1) matched in age, gender and educational background underwent 3T structural and functional MRI scanning while they performed a sequential tapping task with their right or left hand in alternated blocks. Results Compared to rest blocks, active tapping activated the contralateral primary motor, premotor and supplementary motor areas, thalamus and cerebellum in both patients and controls. However, in the right hand condition, patients deactivated the right putamen to a greater extent than controls, which suggests that patients need a greater inhibition of the ipsilateral putamen in order to suppress the movement of the opposite hand. Furthermore, HD patients showed less activation in the right putamen during the left hand condition compared to controls. These effects could be ascribed to the general imbalance in the Go and No-Go cortico-striatal pathways that is believed to occur in HD. The left precentral gyrus, was selected as a seed region for a whole brain functional connectivity analysis. Compared with controls, right precentral gyrus, right SMA and right putamen were more connected (negatively) to the left precentral gyrus in patients. This indicates that not only the right putamen, but all the right motor circuit undergoes a greater deactivation in HD patients when they move their left hand. In addition, the negative functional connectivity between the left precentral gyrus and the right putamen showed a positive correlation with the motor-UHDRS score and the TFC score. Conclusions These results indicate that HD patients need to inhibit the contralateral motor circuit of the moving hand to compensate for the hyperactivation of the dopaminergic system that underlies their motor symptoms. This effect is specific to the right hemisphere, showing an asymmetry of the motor circuit dysfunction.

Patients with Huntington Disease (HD) show poor self-awareness of a variety of symptoms. Previous research in HD has primarily examined awareness of motor symptoms, whereas less attention has been given to unawareness of cognitive function and behavioural disorders. This study aim to assess self-awareness of executive deficits in HD and to explore the association between impaired awareness, cognition (executive function and memory) and evolution of the disease. Self-awareness was tested in 17 patients with HD (8 male, age=50.5 ± 9.8 years) at early stage of the disease (mean TFC 11.7) by comparing patient and family ratings using the Dysexecutive Questionnaire (DEX) with five-factor factorial structure (Inhibition, Intentionality, executive memory, negative and positive affect). Executive and memory functions were assessed by different standardised neuropsychological tests included in cognitive protocol Registry 3. Finally, we extracted the volume of the different striatal substructures (left and right caudate, putamen and nucleus accumbens) as a neuroanatomical signature of disease progression in HD. Statistical analysis revealed a significant discrepancy between the DEX-Family and DEX-Patient specifically in the second factor of DEX (intentionality). This factor contains items about disinhibition, aggression, euphoria, lack of insight and social conscience. We also found that poor insight in this area measured by DEX is significantly and specifically related with the atrophy of the left caudate. None of the cognitive tests that were administrated showed significant correlation with unawareness. Our results are consistent with previous literature, indicating that patients with HD generally overestimate their abilities. This study shows that the awareness of dysexecutive function in HD is not a general and uniform process, but is specific to certain symptoms (predominantly behaviours related with intentionality and disinhibition) and suggests the involvement of specific neuroanatomical substrates for unawareness in HD.

The Mini-Mental State (MMS) is a brief structured test of cognitive function. The purpose of this study was to adapt and normalise MMS for the Spanish population. The test was administered to 450 subjects (253 control volunteers, 86 mild memory/cognitive impairment without dementia subjects - CIWD and 111 Alzheimer's Disease patients - AD). A cross-sectional statistical study in a population stratified by age and education was conducted. A more accurate diagnosis is provided by scores that have been adjusted for age and level of education. The recommended cut-off in our study was 24/25 (non-demented above 24). The adaptation and normalisation of MMS provides the Spanish population with a highly valuable screening tool.

Huntington's disease (HD) is a genetic neurodegenerative disease which involves a triad of motor, cognitive and psychiatric disturbances. However, there is great variability in the prominence of each type of symptom across individuals. The neurobiological basis of such variability remains poorly understood but would be crucial for better tailored treatments. Multivariate multimodal neuroimaging approaches have been successful in disentangling these profiles in other disorders. Thus we applied for the first time such approach to HD. We studied the relationship between HD symptom domains and multimodal measures sensitive to grey and white matter structural alterations. Forty-three HD gene carriers (23 manifest and 20 premanifest individuals) were scanned and underwent behavioural assessments evaluating motor, cognitive and psychiatric domains. We conducted a multimodal analysis integrating different structural neuroimaging modalities measuring grey matter volume, cortical thickness and white matter diffusion indices – fractional anisotropy and radial diffusivity. All neuroimaging measures were entered into a linked independent component analysis in order to obtain multimodal components reflecting common inter-subject variation across imaging modalities. The relationship between multimodal neuroimaging independent components and behavioural measures was analysed using multiple linear regression. We found that cognitive and motor symptoms shared a common neurobiological basis, whereas the psychiatric domain presented a differentiated neural signature. Behavioural measures of different symptom domains correlated with different neuroimaging components, both the brain regions involved and the neuroimaging modalities most prominently associated with each type of symptom showing differences. More severe cognitive and motor signs together were associated with a multimodal component consisting in a pattern of reduced grey matter, cortical thickness and white matter integrity in cognitive and motor related networks. In contrast, depressive symptoms were associated with a component mainly characterised by reduced cortical thickness pattern in limbic and paralimbic regions. In conclusion, using a multivariate multimodal approach we were able to disentangle the neurobiological substrates of two distinct symptom profiles in HD: one characterised by cognitive and motor features dissociated from a psychiatric profile. These results open a new view on a disease classically considered as a uniform entity and initiates a new avenue for further research considering these qualitative individual differences. Keywords: Linked ICA, Data fusion, Huntington's disease, Neurodegeneration, Clinical profiles, Structural MRI

Background The most accurate knowledge about progressive supranuclear palsy (PSP) comes from small sample studies that preclude precise estimation of the proportion of PSP patients affected with various symptoms and the examination of factors predicting survival time. Objectiue To describe the course of PSP in a large clinically diagnosed sample of PSP patients and to identify factors predicting survival time. Methods We surveyed the caregivers of 318 living and 119 deceased patients with progressive supranuclear palsy. The main outcome measures were a principal symptom severity questionnaire and a signs and symptoms questionnaire. Results The estimated age of PSP symptom onset depends critically on how symptom onset is defined, with estimates differing by as much as 1.5 years. Men and women were represented equally (51.6% versus 48.4%) in the living sample, but men formed 61.8% of the deceased sample. Men were diagnosed later than women following symptom onset (33.4 versus 24.1 months) and died earlier following the diagnosis (37.0 versus 47.6 months). Motor and visual symptoms appeared first, followed by emotional and personality problems, cognitive impairment, and sleep changes. Whereas motor symptoms eventually affected almost every patient, emotionallpersonality and cognitive symptoms did not. The early onset, presence of falls, slowness, and inability to move eyes downward early in the development of the disease predicted survival time. Conclusion PSP is a rapidly progressive disease dominated by motor symptoms, and it affects men more frequently than women.