Isabel Almeida

Computer-Assisted Rehabilitation Program - Virtual Reality (CARP-VR): A program for cognitive rehabilitation of executive dysfunction

Every year millions of individuals sustain Acquired Brain Injury (ABI) often resulting in physical, cognitive and psychosocial deficits, leading to life-long changes in the quality of life of patients and their families. In the domain of rehabilitation, virtual-reality (VR) technology has assumed a crucial role in the creation of innovative assessment and training programs. The purpose of this study is to present the Computer-Assisted Rehabilitation Program (CARP-VR) after a brief review of the state of the art. CARP-VR was tailored to the rehabilitation of executive functioning and other related cognitive functions in patients with ABI. It consists of virtual environments that simulate real-life contexts in which patients perform various activities that are based on daily situations. The final version of CARP-VR is now ready to be employed, and tests have been designed to validate it as a tool for the rehabilitation of executive functioning and related cognitive functions.

An fMRI paradigm based on Williams inhibition test to study the neural substrates of attention and inhibitory control

The purpose of this study is to present an fMRI paradigm, based on the Williams inhibition test (WIT), to study attentional and inhibitory control and their neuroanatomical substrates. We present an index of the validity of the proposed paradigm and test whether the experimental task discriminates the behavioral performances of healthy participants from those of individuals with acquired brain injury. Stroop and Simon tests present similarities with WIT, but this latter is more demanding. We analyze the BOLD signal in 10 healthy participants performing the WIT. The dorsolateral prefrontal cortex, the inferior prefrontal cortex, the anterior cingulate cortex, and the posterior cingulate cortex were defined for specified region of interest analysis. We additionally compare behavioral data (hits, errors, reaction times) of the healthy participants with those of eight acquired brain injury patients. Data were analyzed with GLM-based random effects and Mann-Whitney tests. Results show the involvement of the defined regions and indicate that the WIT is sensitive to brain lesions. This WIT-based block design paradigm can be used as a research methodology for behavioral and neuroimaging studies of the attentional and inhibitory components of executive functions.

Study of behavioural and neural bases of visuo-spatial working memory with an fMRI paradigm based on an n-back task.

The goal of this study was to propose a new functional magnetic resonance imaging (fMRI) paradigm using a language-free adaptation of a 2-back working memory task to avoid cultural and educational bias. We additionally provide an index of the validity of the proposed paradigm and test whether the experimental task discriminates the behavioural performances of healthy participants from those of individuals with working memory deficits. Ten healthy participants and nine patients presenting working memory (WM) deficits due to acquired brain injury (ABI) performed the developed task. To inspect whether the paradigm activates brain areas typically involved in visual working memory (VWM), brain activation of the healthy participants was assessed with fMRIs. To examine the tasks capacity to discriminate behavioural data, performances of the healthy participants in the task were compared with those of ABI patients. Data were analysed with GLM-based random effects procedures and t-tests. We found an increase of the BOLD signal in the specialized areas of VWM. Concerning behavioural performances, healthy participants showed the predicted pattern of more hits, less omissions and a tendency for fewer false alarms, more self-corrected responses, and faster reaction times, when compared with subjects presenting WM impairments. The results suggest that this task activates brain areas involved in VWM and discriminates behavioural performances of clinical and non-clinical groups. It can thus be used as a research methodology for behavioural and neuroimaging studies of VWM in block-design paradigms.

GANDRA-BARTA FOR THE ASSESSMENT OF FACIAL EMOTION RECOGNITION IN ACQUIRED BRAIN INJURY

Patients with acquired brain injury (ABI) may experience social difficulties more specifically in the emotional recognition of faces. The present research aims to test the discriminative validity of GandraBARTA to the changes in the emotional recognition of faces after ABI and to perceive its connection with the general cognitive functioning, executive functioning and other variables associated with ABI. The sample consists of two groups, the Clinical Group (n=20, ABI participants) and the Control Group (n=16, healthy participants). All participants underwent a global cognitive assessment through the Montreal Cognitive Assessment (MoCA), executive functioning was measured by INECO Frontal Screening and the evaluation of emotional recognition of faces through Gandra-BARTA. The results demonstrate that Gandra-BARTA presents discriminative capacity for the evaluation of the emotional recognition of faces in patients with acquired brain injury. We observed differences between the two groups in the capacity of emotional recognition especially in the identification of emotions such as anger, disgust, happiness and surprise. The study also shows the existence of a decline in the identification of emotions with age, in the recognition of the disgusting stimuli presents a deficit related to the age and executive functioning, while with the rage the decline is related to the age and schooling. The emotional recognition of faces presents improvements with time after injury. Identification of the neutral expression demonstrates an improvement over time after injury. The discriminative ability of Gandra-BARTA allows it to be an instrument to be used in the evaluation of the emotional recognition of faces in patients with acquired brain injury. Individuals with brain injury have difficulties in identifying anger, disgust, happiness and surprise. Emotional recognition differs in relation to age, executive functioning, schooling, and time after injury.

P-784 - A new fMRI paradigm to study behavioral and neural bases of visual working memory

Introduction Working memory (WM) is a cognitive process that refers to storing information in a temporary system that allows monitoring and handling this information. Objectives To propose and validate a new fMRI paradigm to study WM and its neuroanatomical substrates, using a language-free adaptation of the 2-back working memory task in order to avoid cultural and educational bias. Aims To test the hypothesis that the proposed paradigm would produce an increase of the BOLD signal in specialized areas for spatial WM (Superior Frontal Sulcus) and areas for monitoring and handling this information (Dorsolateral Prefrontal Cortex) in healthy participants. We also expected a significantly higher behavioral performance in this group than in subjects with suspected WM impairment due to acquired brain injury. Methods 10 neurologically healthy participants and 11 ABI participants performed the task in a block design experiment with four runs. These observed a 9-square matrix with one of the squares painted black and pressed a button each time the black square was the same as the one two trials back. We analyzed behavioral performance and brain activation in repeated trials. Results Higher BOLD activation of brain regions was associated with the performance of the WM task in the healthy group, as well as better behavioral performance. We also present behavior results of both groups, so these data can be compared to other clinical groups with suspected WM deficits. Conclusions This task may be used as a research methodology for behavioral and neuroimaging studies of visual WM in block-design paradigms.