Revistas
Revista:
FRONTIERS IN AGING NEUROSCIENCE
ISSN:
1663-4365
Año:
2022
Vol.:
13
Págs.:
778201
The human brain undergoes structural and functional changes across the lifespan. The study of motor sequence learning in elderly subjects is of particularly interest since previous findings in young adults might not replicate during later stages of adulthood. The present functional magnetic resonance imaging (fMRI) study assessed the performance, brain activity and functional connectivity patterns associated with motor sequence learning in late middle adulthood. For this purpose, a total of 25 subjects were evaluated during early stages of learning [i.e., fast learning (FL)]. A subset of these subjects (n = 11) was evaluated after extensive practice of a motor sequence [i.e., slow learning (SL) phase]. As expected, late middle adults improved motor performance from FL to SL. Learning-related brain activity patterns replicated most of the findings reported previously in young subjects except for the lack of hippocampal activity during FL and the involvement of cerebellum during SL. Regarding functional connectivity, precuneus and sensorimotor lobule VI of the cerebellum showed a central role during improvement of novel motor performance. In the sample of subjects evaluated, connectivity between the posterior putamen and parietal and frontal regions was significantly decreased with aging during SL. This age-related connectivity pattern may reflect losses in network efficiency when approaching late adulthood. Altogether, these results may have important applications, for instance, in motor rehabilitation programs.
Revista:
FRONTIERS IN AGING NEUROSCIENCE
ISSN:
1663-4365
Año:
2022
Vol.:
14
Págs.:
936661
The ability to appropriately perceive distances in activities of daily living, such as driving, is necessary when performing complex maneuvers. With aging, certain driving behaviors and cognitive functions change; however, it remains unknown if egocentric distance perception (EDP) performance is altered and whether its neural activity also changes as we grow older. To that end, 19 young and 17 older healthy adults drove in a driving simulator and performed an functional magnetic resonance imaging (fMRI) experiment where we presented adults with an EDP task. We discovered that (a) EDP task performance was similar between groups, with higher response times in older adults; (b) older adults showed higher prefrontal and parietal activation; and (c) higher functional connectivity within frontal and parietal-occipital-cerebellar networks; and (d) an association between EDP performance and hard braking behaviors in the driving simulator was found. In conclusion, EDP functioning remains largely intact with aging, possibly due to an extended and effective rearrangement in functional brain resources, and may play a role in braking behaviors while driving.
Revista:
FRONTIERS IN PSYCHOLOGY
ISSN:
1664-1078
Año:
2022
Vol.:
12
Págs.:
686928
Rather than occurring abstractly (autonomously), ethical growth occurs in interpersonal relationships (IRs). It requires optimally functioning cognitive processes [attention, working memory (WM), episodic/autobiographical memory (AM), inhibition, flexibility, among others], emotional processes (physical contact, motivation, and empathy), processes surrounding ethical, intimacy, and identity issues, and other psychological processes (self-knowledge, integration, and the capacity for agency). Without intending to be reductionist, we believe that these aspects are essential for optimally engaging in IRs and for the personal constitution. While they are all integrated into our daily life, in research and academic work, it is hard to see how they are integrated. Thus, we need better theoretical frameworks for studying them. That study and integration thereof are undertaken differently depending on different views of what it means to live as a human being. We rely on neuroscientific data to support the chosen theory to offer knowledge to understand human beings and interpersonal relational growth. We should of course note that to describe what makes up the uniqueness of being, acting, and growing as a human person involves something much more profound which requires too, a methodology that opens the way for a theory of the person that responds to the concerns of philosophy and philosophical anthropology from many disciplines and methods (Oron Semper, 2015; Polo, 2015), but this is outside the scope of this study. With these in mind, this article aims to introduce a new explanatory framework, called the Interprocessual-self (IPS), for the neuroscientific findings that allow for a holistic consideration of the previously mentioned processes. Contributing to the knowledge of personal growth and avoiding a reductionist view, we first offer a general description of the research that supports the interrelation between personal virtue in IRs and relevant cognitive, emotional, and ethic-moral processes. This reveals how relationships allow people to relate ethically and grow as persons. We include conceptualizations and descriptions of their neural bases. Secondly, with the IPS model, we explore neuroscientific findings regarding self-knowledge, integration, and agency, all psychological processes that stimulate inner exploration of the self concerning the other. We find that these fundamental conditions can be understood from IPS theory. Finally, we explore situations that involve the integration of two levels, namely the interpersonal one and the social contexts of relationships.
Revista:
BRAIN IMAGING AND BEHAVIOR
ISSN:
1931-7557
Año:
2022
Vol.:
16
N°:
3
Págs.:
1349-1361
Recent imaging studies with the stop-signal task in healthy individuals indicate that the subthalamic nucleus, the pre-supplementary motor area and the inferior frontal gyrus are key components of the right hemisphere ¿inhibitory network¿. Limited information is available regarding neural substrates of inhibitory processing in patients with asymmetric Parkinson¿s disease. The aim of the current fMRI study was to identify the neural changes underlying deficient inhibitory processing on the stop-signal task in patients with predominantly left-sided Parkinson's disease. Fourteen patients and 23 healthy controls performed a stop-signal task with the left and right hands. Behaviorally, PD patients showed delayed response inhibition with either hand compared to controls. We found small imaging differences for the right hand, however for the more affected left hand when behavior was successfully inhibited we found reduced activation of the inferior frontal gyrus bilaterally and the insula. Using the stop-signal delay as regressor, contralateral underactivation in the right dorsolateral prefrontal cortex, inferior frontal and anterior putamen were found in patients. This finding indicates dysfunction of the right inhibitory network in left-sided PD. Functional connectivity analysis of the left subthalamic nucleus showed a significant increase of connectivity with bilateral insula. In contrast, the right subthalamic nucleus showed increased connectivity with visuomotor and sensorimotor regions of the cerebellum. We conclude that altered inhibitory control in left-sided Parkinson's disease is associated with reduced activation in regions dedicated to inhibition in healthy controls, which then requires engagement of additional regions not observed in controls to successfully stop ongoing actions.
Revista:
FRONTIERS IN PSYCHOLOGY
ISSN:
1664-1078
Año:
2022
Vol.:
13
Págs.:
856558
The aim of this research was to delimit the predictive and mediational model of resilience between character strengths to predict flourishing, in a sample of undergraduate students. After signing their informed consent, 642 university students completed three validated scales. Using an ex post facto design, regression, structural modeling, and mediation analyses were carried out, in order to construct a multi-causal predictive model. Results indicated a consistent predictive direct effect of character strengths on resilience and flourishing and of resilience on flourishing. As hypothesized, resilience also showed a mediating effect on the relationship between character strengths and flourishing. Additionally, results also revealed that the reactive and proactive factors of resilience were explained by different character strengths, reinforcing the idea that the two directions are complementary and necessary. Finally, several implications were established for the practice of positive psychology.
Autores:
Wang, K.; Goldenberg, A.; Dorison, C.A.; et al.
Revista:
NATURE HUMAN BEHAVIOUR
ISSN:
2397-3374
Año:
2021
Vol.:
5
N°:
8
Págs.:
1089-1110
The COVID-19 pandemic has increased negative emotions and decreased positive emotions globally. Left unchecked, these emotional changes might have a wide array of adverse impacts. To reduce negative emotions and increase positive emotions, we tested the effectiveness of reappraisal, an emotion-regulation strategy that modifies how one thinks about a situation. Participants from 87 countries and regions (n=21,644) were randomly assigned to one of two brief reappraisal interventions (reconstrual or repurposing) or one of two control conditions (active or passive). Results revealed that both reappraisal interventions (vesus both control conditions) consistently reduced negative emotions and increased positive emotions across different measures. Reconstrual and repurposing interventions had similar effects. Importantly, planned exploratory analyses indicated that reappraisal interventions did not reduce intentions to practice preventive health behaviours. The findings demonstrate the viability of creating scalable, low-cost interventions for use around the world.
Revista:
INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH
ISSN:
1660-4601
Año:
2021
Vol.:
18
N°:
5
Págs.:
2253
The aim of the present cross-sectional study was to analyze the differential impact of the first COVID-19 lockdown (3rd April 2020) on stress, health practices, and self-care activities across different Hispanic countries, age range and gender groups. 1082 participants from Spain, Chile, Colombia, and Ecuador took part in this study. Irrespective of the country, and controlling for income level, young people, especially females, suffered a greater level of stress, perceived the situation as more severe, showed less adherence to health guidelines and reported lower levels of health consciousness, in comparison to their male peers and older groups. However, in the case of self-care, it seems that older and female groups are generally more involved in self-care activities and adopt more healthy daily routines. These results are mostly similar between Colombia, Ecuador, and Spain. However, Chile showed some different tendencies, as males reported higher levels of healthy daily routines and better adherence to health guidelines compared to females and people over the age of 60. Differences between countries, genders and age ranges should be considered in order to improve health recommendations and adherence to guidelines. It would also be crucial to identify vulnerable groups to promote the adoption of health behaviors that may help in the development of effective public health strategies. Future studies should be addressed to explore the possible causations of such [...]
Revista:
JOURNAL OF THEORETICAL AND PHILOSOPHICAL PSYCHOLOGY
ISSN:
1068-8471
Año:
2021
Vol.:
41
N°:
2
Págs.:
115 - 130
This article offers a proposal related to early childhood emotional education. It is in line with Erikson's (1959) ideas surrounding psychosocial development and his theory of attachment and social referencing, Bridges' (1932) emotional development scheme, and Rogers' notion related to "acceptance" of emotional complexity toward healthy development. This proposal is reinforced with approaches from Winnicott (1986) and Kohut (2009), who demonstrate that children's emotional education is indeed a process of self-consciousness development through interaction with their primary caregiver(s). These approaches demonstrate that early childhood emotional education is really a process related to children's development of self-consciousness through interaction, or lack thereof, with their primary caregiver(s). We coin our approach "emotional integration," which is conceptualized as a response to the dominant "emotional regulation" narrative. While emotional regulation focuses on behavioral and structured routines for facing diverse emotional situations, emotional integration is centered on interpersonal relationship improvements in different emotional contexts. For the emotional regulation approach, the child regulates her behavior depending on the primary caregiver's reactions. In emotional integration, the child acquires certain dispositions toward the self, starting from her interaction with her caregiver. In small children, caregiver behavior certainly has a determining role. For the emotional regulation approach, the caregiver tries to solve possible problems in behavior, whereas for emotional integration, the caregiver seeks to develop inner processes of personal growth through the child's interaction with the other.
Revista:
BMJ OPEN
ISSN:
2044-6055
Año:
2021
Vol.:
11
N°:
2
Págs.:
e048469
Objectives To examine the mediation role of self-care between stress and psychological well-being in the general population of four countries and to assess the impact of sociodemographic variables on this relationship. Design Cross-sectional, online survey. Participants A stratified sample of confined general population (N=1082) from four Ibero-American countries-Chile (n=261), Colombia (n=268), Ecuador (n=282) and Spain (n=271)-balanced by age and gender. Primary outcomes measures Sociodemographic information (age, gender, country, education and income level), information related to COVID-19 lockdown (number of days in quarantine, number of people with whom the individuals live, absence/presence of adults and minors in charge and attitude towards the search of information related to COVID-19), Perceived Stress Scale-10, Ryff's Psychological Well-Being Scale-29 and Self-Care Activities Screening Scale-14. Results Self-care partially mediates the relationship between stress and well-being during COVID-19 confinement in the general population in the total sample (F (3,1078)=370.01, p<0.001, R-2=0.507) and in each country. On the other hand, among the evaluated sociodemographic variables, only age affects this relationship. Conclusion The results have broad implications for public health, highlighting the importance of promoting people's active role in their own care and health behaviour to improve psychological well-being if stress management and social determinants of health are jointly addressed first. The present study provides the first transnational evidence from the earlier stages of the COVID-19 lockdown, showing that the higher perception of stress, the less self-care activities are adopted, and in turn the lower the beneficial effects on well-being.
Revista:
PERSONALITY AND INDIVIDUAL DIFFERENCES
ISSN:
0191-8869
Año:
2021
Vol.:
177
Págs.:
110679
Revista:
HEALTH AND QUALITY OF LIFE OUTCOMES
ISSN:
1477-7525
Año:
2021
Vol.:
19
N°:
1
Págs.:
1
In a context where there is no treatment for the current COVID-19 virus, the combination of self-care behaviours together with confinement, are strategies to decrease the risk of contagion and remain healthy. However, there are no self-care measures to screen self-care activities in general population and which, could be briefly in a lockdown situation. This research aims to build and validate a psychometric tool to screen self-care activities in general population.
Firstly, an exploratory factor analysis was performed in a sample of 226 participants to discover the underlying factorial structure and to reduce the number of items in the original tool into a significant pool of items related to self-care. Later a confirmatory factor analyses were performed in a new sample of 261 participants to test for the fit and goodness of factor solutions. Internal validity, reliability, and convergent validity between its score with perceived stress and psychological well-being measures were examined on this sample.
The exploratory analyses suggested a four-factor solution, corresponding to health consciousness, nutrition and physical activity, sleep, and intra-personal and inter-personal coping skills (14 items). Then, the four-factor structure was confirmed as the best model fit for self-care activities. The tool demonstrated good reliability, predictive validity of individuals¿ perception of coping with COVID-19 lockdown, and convergent validity with well-being and perceived stress.
Revista:
HUMAN MOLECULAR GENETICS
ISSN:
0964-6906
Año:
2020
Vol.:
29
N°:
19
Págs.:
3211 - 3223
Revista:
NEUROIMAGE
ISSN:
1053-8119
When humans make decisions, objective rewards are mainly discounted by delay, risk and effort. Whereas recentresearch has demonstrated that several brain areas process costs and code subjective value in effort-based decisionmaking, it remains obscure how neural activity patterns change when effort costs are reduced due to theacquisition of healthy habits, such as moving from sedentary to active lifestyles. Here, a sample of sedentaryvolunteers was behaviorally assessed and fMRI-scanned before and after completing a 3-monthfitness plan. Theimpact of effort cost on decisions, measured as the constant defining a hyperbolic decaying function, was reducedafter the plan. A logistic mixed model demonstrated that the explanatory power of effort decreased with time. At aneural level, there was a marginally significant disruption of effort-cost related functional activity in the anteriorcingulate after the plan. Functional connectivity between the amygdala and anterior cingulate cortex wasstrengthened after habit acquisition. In turn, this interaction was stronger in those participants with lower effortdiscounting. Thus, we show for thefirst time changes in value-based decision making after moving from asedentary to an active lifestyle, which points to the relevance of the amygdala-cingulate interplay when theimpact of effort on decisions fades away.
Revista:
EUROPEAN JOURNAL OF CHILD DEVELOPMENT, EDUCATION AND PSYCHOPATHOLOGY
ISSN:
2340-924X
Año:
2019
Vol.:
7
N°:
2
Págs.:
107-118
Revista:
CORTEX
ISSN:
0010-9452
Año:
2019
Vol.:
113
Págs.:
96-110
According to the theory of value-based decision making, subjects tend to choose the most valuable among a set of options. However, agents may not be consistent when facing the same decision several times. In this paper, Shannon¿s entropy (H) is employed as a measure of behavioral inconsistency: it is a central measure of information theory that, applied to decision making, allows the estimation of behavioral preferences among a set of options. We scanned (functional magnetic resonance imaging, fMRI) 24 young (18-25 year) subjects (14 female) while performing a decision-making task, where monetary rewards were devalued by physical effort (minutes running in the treadmill) and risk. Twenty different pairs of options were presented nine times each, and H was calculated for each pair and subject. Behavioral analyses showed that subjective value (SV) significantly explained agents¿ preferences only in pairs with a low inconsistent response. Averaged response time positively correlated with H, confirming entropy as an indicator of choice difficulty. Group analyses on fMRI data revealed a cluster in the paracingulate cortex as the neural correlate of H. Besides, BOLD signal in the posterior cingulate correlated with the SV of the pair only in consistent decisions, confirming that SV loses its explanatory power on highly inconsistent decisions. Finally, the anterior and central cingulate were especially recruited when predicting a secured effortless reward, compared with a secured re
Revista:
HUMAN BRAIN MAPPING
ISSN:
1065-9471
Año:
2018
Vol.:
39
N°:
11
Págs.:
4196 - 4212
Numerous daily tasks, including car driving, require fine visuospatial tuning. One such visuospatial ability, speed discrimination, declines with aging but its neural underpinnings remain unknown. In this study, we use fMRI to explore the effect of aging during a high speed discrimination task and its neural underpinnings, along with a complete neuropsychological assessment and a simulated driving evaluation in order to examine how they interact with each other through a multivariate regression approach. Beyond confirming that high speed discrimination performance is diminished in the elderly, we found that this deficit might be partly due to a lack of modulation in the activity and connectivity of the default mode network (DMN) in this age group, as well as an over-recruitment of frontoparietal and cerebellar regions, possibly as a compensatory mechanism. In addition, younger adults tended to drive at faster speeds, a behavior that was associated to adequate DMN dynamics and executive functioning, an effect that seems to be lost in the elderly. In summary, these results reveal how age-related declines in fine visuospatial abilities, such as high speed discrimination, were distinctly mediated by DMN functioning, a mechanism also associated to speeding behavior in a driving simulator.
Revista:
SCIENTIFIC REPORTS
ISSN:
2045-2322
Año:
2018
Vol.:
8
Págs.:
7584
Poisoning, a subtype of physical injury, is an important hazard in children and youth. Individuals with ADHD may be at higher risk of poisoning. Here, we conducted a systematic review and meta-analysis to quantify this risk. Furthermore, since physical injuries, likely share causal mechanisms with those of poisoning, we compared the relative risk of poisoning and injuries pooling studies reporting both. As per our pre-registered protocol (PROSPERO ID CRD42017079911), we searched 114 databases through November 2017. From a pool of 826 potentially relevant references, screened independently by two researchers, nine studies (84,756 individuals with and 1,398,946 without the disorder) were retained. We pooled hazard and odds ratios using Robust Variance Estimation, a meta-analytic method aimed to deal with non-independence of outcomes. We found that ADHD is associated with a significantly higher risk of poisoning (Relative Risk = 3.14, 95% Confidence Interval = 2.23 to 4.42). Results also indicated that the relative risk of poisoning is significantly higher than that of physical injuries when comparing individuals with and without ADHD (Beta coefficient = 0.686, 95% Confidence Interval = 0.166 to 1.206). These findings should inform clinical guidelines and public health programs aimed to reduce physical risks in children/adolescents with ADHD.
Revista:
NEUROSCIENCE AND BIOBEHAVIORAL REVIEWS
ISSN:
0149-7634
Año:
2018
Vol.:
84
Págs.:
63-71
A systematic review with meta-analyses was performed to: 1) quantify the association between ADHD and risk of unintentional physical injuries in children/adolescents ("risk analysis"); 2) assess the effect of ADHD medications on this risk ("medication analysis"). We searched 114 databases through June 2017. For the risk analysis, studies reporting sex-controlled odds ratios (ORs) or hazard ratios (HRs) estimating the association between ADHD and injuries were combined. Pooled ORs (28 studies, 4,055,620 individuals without and 350,938 with ADHD) and HRs (4 studies, 901,891 individuals without and 20,363 with ADHD) were 1.53 (95% CI=1.40,1.67) and 1.39 (95% CI=1.06,1.83), respectively. For the medication analysis, we meta-analysed studies that avoided the confounding-by-indication bias [four studies with a self-controlled methodology and another comparing risk over time and groups (a "difference in differences" methodology)]. The pooled effect size was 0.879 (95% CI=0.838,0.922) (13,254 individuals with ADHD). ADHD is significantly associated with an increased risk of unintentional injuries and ADHD medications have a protective effect, at least in the short term, as indicated by self-controlled studie
Revista:
BRAIN IMAGING AND BEHAVIOR
ISSN:
1931-7557
Año:
2017
Vol.:
11
N°:
4
Págs.:
986 - 997
Previous research on motor sequence learning (MSL) in the elderly has focused mainly on unilateral tasks, even though bilateral coordination might be impaired in this age group. In this fMRI study, 28 right-handed elderly subjects were recruited. The paradigm consisted of a Novel and a simple Control sequence executed with the right (R), left (L) and both hands (B). Behavioral performance (Accuracy[AC], Inter-tap Interval[ITI]) and associated brain activity were assessed during early learning. Behavioral performance in the Novel task was similar between unilateral conditions whereas in the bimanual condition more errors and slower motor execution were observed. Brain activity increases during learning showed differences between Conditions: R showed increased activity in pre-SMA, basal ganglia and left hippocampus while B showed activity increments mainly in posterior parietal cortex and cerebellum. L did not show any activity modulation during learning. Performance correlates for AC (related to spatial success) and ITI (related to accurate timing) shared a cortico-basal-cerebellar network. However, it was found that the ITI regressor presented additional significant correlations with activity in SMA and basal ganglia in R. The AC regressor showed additional significant correlations with activity in more extended thalamic and cerebellar areas in B. The present findings suggest that, behaviorally, the spatial and temporal components of MSL are impaired in elderly subjects when using both hands. Additionally, differential brain activity patterns were found across hand modalities. The results obtained reveal the existence of a highly specialized network in the dominant hand and identify areas specifically involved in bimanual coordination.
Revista:
BMJ OPEN
ISSN:
2044-6055
Año:
2017
Vol.:
7
N°:
9
Págs.:
e018027
Attention-deficit hyperactivity disorder (ADHD) has been related to increased rates of unintentional injuries. However, the magnitude of the effect and to which extent variables such as sex, age or comorbidity can influence this relationship is unknown. Additionally, and importantly, it is unclear if, and to which degree, ADHD medications can decrease the number of unintentional injuries. Due to the amount of economic and social resources invested in the treatment of injuries, filling these gaps in the literature is highly relevant from a public health standpoint. Here, we present a protocol for a systematic review and meta-analysis to estimate the relationship between ADHD and unintentional injuries and assess the impact of pharmacological treatment for ADHD METHODS AND ANALYSIS: We will combine results from 114 bibliographic databases for studies relating ADHD and risk of injuries. Bibliographic searches and data extraction will be carried out independently by two researchers. The studies' risk of bias will be assessed using the Newcastle-Ottawa Scale. Articles reporting ORs or HRs of suffering an injury in ADHD compared with controls (or enough data to calculate them) will be combined using Robust Variance Estimation, a method that permits to include multiple non-independent outcomes in the analysis. All analyses will be carried out in Stata. Age, sex and comorbid conduct disorders will be considered as potential causes of variance and their effect analysed through meta-re
Revista:
JOURNAL OF PLASTIC RECONSTRUCTIVE AND AESTHETIC SURGERY
ISSN:
1748-6815
Año:
2016
Vol.:
69
N°:
3
Págs.:
417-426
Several techniques have been described for smile restoration after facial nerve paralysis. When a nerve other than the contralateral facial nerve is used to restore the smile, some controversy appears because of the nonphysiological mechanism of smile recovering. Different authors have reported natural results with the masseter nerve. The physiological pathways which determine whether this is achieved continue to remain unclear. Using functional magnetic resonance imaging, brain activation pattern measuring blood-oxygen-level-dependent (BOLD) signal during smiling and jaw clenching was recorded in a group of 24 healthy subjects (11 females). Effective connectivity of premotor regions was also compared in both tasks. The brain activation pattern was similar for smile and jaw-clenching tasks. Smile activations showed topographic overlap though more extended for smile than clenching. Gender comparisons during facial movements, according to kinematics and BOLD signal, did not reveal significant differences. Effective connectivity results of psychophysiological interaction (PPI) from the same seeds located in bilateral facial premotor regions showed significant task and gender differences (p < 0.001). The hypothesis of brain plasticity between the facial nerve and masseter nerve areas is supported by the broad cortical overlap in the representation of facial and masseter muscles.
Revista:
JOURNAL OF ALZHEIMERS DISEASE
ISSN:
1387-2877
Año:
2016
Vol.:
53
N°:
1
Págs.:
303 - 313
Background: Frontotemporal lobar degeneration (FTLD) is a progressive dementia characterized by focal atrophy of frontal and/or temporal lobes caused by mutations in the gene coding for sequestosome 1 (SQSTM1), among other genes. Rare SQSTM1 gene mutations have been associated with Paget¿s disease of bone, amyotrophic lateral sclerosis, and, more recently, frontotemporal lobar degeneration (FTLD).
Objective: The aim of the study was to determine whether a characteristic pattern of grey and white matter loss is associated with SQSTM1 dysfunction.
Methods: We performed a voxel-based morphometry (VBM) study in FTD subjects carrying SQSTM1 pathogenic variants (FTD/SQSTM1 mutation carriers; n¿=¿10), compared with FTD subjects not carrying SQSTM1 mutations (Sporadic FTD; n¿=¿20) and healthy controls with no SQSTM1 mutations (HC/SQSTM1 noncarriers; n¿=¿20). The groups were matched according to current age, disease duration, and gender.
Results: After comparing FTD/SQSTM1 carriers with Sporadic FTD, a predominantly right cortical atrophy pattern was localized in the inferior frontal, medial orbitofrontal, precentral gyri, and the anterior insula. White matter atrophy was found in both medial and inferior frontal gyri, pallidum, and putamen. FTD/SQSTM1 carriers compared with HC/SQSTM1 noncarriers showed atrophy at frontal, temporal, and parietal lobes of both hemispheres whereas the MRI pattern found in Sporadic FTD compared with controls was frontal and left temporal lobe atrophy, extending toward parietal and occipital lobes of both hemispheres.
Conclusions: These results suggest that fronto-orbito-insular regions including corticospinal projections as described in ALS are probably more susceptible to the damaging effect of SQSTM1 mutations delineatinga specific gene-linked atrophy pattern.
Revista:
HUMAN BRAIN MAPPING
ISSN:
1065-9471
Año:
2016
Vol.:
37
N°:
5
Págs.:
1722 - 1737
The central nervous system has the ability to adapt our locomotor pattern to produce a wide range of gait modalities and velocities. In reacting to external pacing stimuli, deviations from an individual preferred cadence provoke a concurrent decrease in accuracy that suggests the existence of a trade-off between frequency and precision; a compromise that could result from the specialization within the control centers of locomotion to ensure a stable transition and optimal adaptation to changing environment. Here, we explore the neural correlates of such adaptive mechanisms by visually guiding a group of healthy subjects to follow three comfortable stepping frequencies while simultaneously recording their BOLD responses and lower limb kinematics with the use of a custom-built treadmill device. In following the visual stimuli, subjects adopt a common pattern of symmetric and anti-phase movements across pace conditions. However, when increasing the stimulus frequency, an improvement in motor performance (precision and stability) was found, which suggests a change in the control mode from reactive to predictive schemes. Brain activity patterns showed similar BOLD responses across pace conditions though significant differences were observed in parietal and cerebellar regions. Neural correlates of stepping precision were found in the insula, cerebellum, dorsolateral pons and inferior olivary nucleus, whereas neural correlates of stepping stability were found in a distributed network, suggesting a transition in the control strategy across the stimulated range of frequencies: from unstable/reactive at lower paces (i.e., stepping stability managed by subcortical regions) to stable/predictive at higher paces (i.e., stability managed by cortical regions).
Revista:
PLOS ONE
ISSN:
1932-6203
Año:
2015
Vol.:
10
N°:
7
Págs.:
e0131536
BACKGROUND:
Imaging studies help to understand the evolution of key cognitive processes related to aging, such as working memory (WM). This study aimed to test three hypotheses in older adults. First, that the brain activation pattern associated to WM processes in elderly during successful low load tasks is located in posterior sensory and associative areas; second, that the prefrontal and parietal cortex and basal ganglia should be more active during high-demand tasks; third, that cerebellar activations are related to high-demand cognitive tasks and have a specific lateralization depending on the condition.
METHODS:
We used a neuropsychological assessment with functional magnetic resonance imaging and a core N-back paradigm design that was maintained across the combination of four conditions of stimuli and two memory loads in a sample of twenty elderly subjects.
RESULTS:
During low-loads, activations were located in the visual ventral network. In high loads, there was an involvement of the basal ganglia and cerebellum in addition to the frontal and parietal cortices. Moreover, we detected an executive control role of the cerebellum in a relatively symmetric fronto-parietal network. Nevertheless, this network showed a predominantly left lateralization in parietal regions associated presumably with an overuse of verbal storage strategies. The differential activations between conditions were stimuli-dependent and were located in sensory areas.
CONCLUSION:
Successful WM processes in the elderly population are accompanied by an activation pattern that involves cerebellar regions working together with a fronto-parietal network.
Revista:
NEUROBIOLOGY OF AGING
ISSN:
0197-4580
Año:
2014
Vol.:
35
N°:
12
Págs.:
2681-90
A rare heterozygous TREM2 variant p.R47H (rs75932628) has been associated with an increased risk for Alzheimer's disease (AD). We aimed to investigate the clinical presentation, neuropsychological profile, and regional pattern of gray matter and white matter loss associated with the TREM2 variant p.R47H, and to establish which regions best differentiate p.R47H carriers from noncarriers in 2 sample sets (Spanish and Alzheimer's Disease Neuroimaging Initiative, ADNI1). This was a cross-sectional study including a total number of 16 TREM2 p.R47H carriers diagnosed with AD or mild cognitive impairment, 75 AD p.R47H noncarriers and 75 cognitively intact TREM2 p.R47H noncarriers. Spanish AD TREM2 p.R47H carriers showed apraxia (9 of 9) and psychiatric symptoms such as personality changes, anxiety, paranoia, or fears more frequently than in AD noncarriers (corrected p = 0.039). For gray matter and white matter volumetric brain magnetic resonance imaging voxelwise analyses, we used statistical parametric mapping (SPM8) based on the General Linear Model. We used 3 different design matrices with a full factorial design. Voxel-based morphometry analyses were performed separately in the 2 sample sets. The absence of interset statistical differences allowed us to perform joint and conjunction analyses. Independent voxel-based morphometry analysis of the Spanish set as well as conjunction and joint analyses revealed substantial gray matter loss in orbitofrontal cortex and anterior cingulate cortex with relative preservation of parietal lobes in AD and/or mild cognitive impairment TREM2 p.R47H carriers, suggesting that TREM2 p.R47H variant is associated with certain clinical and neuroimaging AD features in addition to the increased TREM2 p.R47H atrophy in temporal lobes as described previously. The high frequency of pathologic behavioral symptoms, combined with a preferential frontobasal gray matter cortical loss, suggests that frontobasal and temporal regions could be more susceptible to the deleterious biological effects of the TREM2 variant p.R47H.
Revista:
IEEE TRANSACTIONS ON MEDICAL IMAGING
ISSN:
0278-0062
Año:
2014
Vol.:
33
N°:
5
Págs.:
1044 - 1053
Repetitive and alternating lower limb movements are a specific component of human gait. Due to technical challenges, the neural mechanisms underlying such movements have not been previously studied with functional magnetic resonance imaging. In this study, we present a novel treadmill device employed to investigate the kinematics and the brain activation patterns involved in alternating and repetitive movements of the lower limbs. Once inside the scanner, 19 healthy subjects were guided by two visual cues and instructed to perform a motor task which involved repetitive and alternating movements of both lower limbs while selecting their individual comfortable amplitude on the treadmill. The device facilitated the performance of coordinated stepping while registering the concurrent lower-limb displacements, which allowed us to quantify some movement primary kinematic features such as amplitude and frequency. During stepping, significant blood oxygen level dependent signal increases were observed bilaterally in primary and secondary sensorimotor cortex, the supplementary motor area, premotor cortex, prefrontal cortex, superior and inferior parietal lobules, putamen and cerebellum, regions that are known to be involved in lower limb motor control. Brain activations related to individual adjustments during motor performance were identified in a right lateralized network including striatal, extrastriatal, and fronto-parietal areas.
