One main focus of research is the cognitive neuroscience of language and executive function, particularly on language learning, bilingual processing and human action monitoring (human error detection and correction processes). In this research we combine the use of different neuroimaging techniques (electrophysiological and magnetic resonance imaging) which are crucial in order to better understand human cognitive functions. Also we have developed new paradigms related to some main research questions: how do we learn a new language? In this respect, we have carried out a large number of experiments with the aim of evaluating and testing different models, which will be further explored using neuroimaging tools. Finally, we have been also studying in which degree genetic variability related to certain neurotransmitters (dopamine) influences cognitive processing, and specially, the way in which we process erroneous actions and reward experiences.
LANGUAGE LEARNING AND HUNTINGTON DISEASE
This research combines information from brain-damaged patients and imaging in healthy individuals to understand whether words and rules of language require different neural and cognitive mechanisms to be acquired since the earliest stages of contact with a new language. We are particularly interested in the role of the striatum as a brain structure that could make the interface between language and other cognitive functions necessary in the learning process.
ACTION MONITORING AND REWARD PROCESSING
In the same line, we are interested is action monitoring and reward processing. The goal is to study the neurophysiological activation patterns generated during the use of executive functions, especially in action monitoring and reward processing, and the relationship between these two systems. It is known that the medial frontal cortex (especially the anterior cingulated cortex) is involved in the processing of cerebral executive functions. Moreover, the reinforcement learning theory suggests that an activation/deactivation of dopaminergic neurons in the midbrain could modulate executive functions such as the processing of error, conflict and reward. In this project we study these relations by functional neuroimaging techniques: functional magnetic resonance (fMRI), electro-encephalography (EEG) and magnetoencephalography (MEG). The information provided by these techniques is critical to our understanding of cerebral function. Hence, study of the oscillatory patterns of brain electrical activity enables us to describe several processes that are not accessible by traditional filtering and averaging methods employed in event-related potentials computation. Patterns of high-frequency EEG activity have been related to synchronization of distant neural populations. Given that fMRI studies show that positive outcomes are evaluated by the orchestration of a sparse net of structures related to the emotions and reward processing, its electrical processing could be reflected as beta and gamma (>20 Hz) M/EEG activity. Hence the frequency study of M/EEG activity is not additional information, but critical.
MUSICAL-THERAPY INDUCED PLASTICITY IN THE SENSORIMOTOR CORTEX AFTER STROKE
A new multidisciplinary approach (neurology, neuropsychology, music and cognitive neurosciences) has been undertaken in order to investigate the effectiveness of a new Musical-Therapy (MT) as a neurorehabilitation technique. This new MT approach has been developed in order to improve the use of the affected upper extremity after stroke (Schneider et al., 2007). The rationale behind this therapy is that motor amelioration will occur because music training promotes auditory-motor coupling. Preliminary data has shown positive effects of this intervention. However the effects and generalization of the MT have not been contrasted appropriately with conventional therapy or with a group in which the other well-known neuroscience-based rehabilitation technique, Constraint-Induced Movement therapy (CIT), has been used.
The present coordinated project investigates the complex pattern of reorganization and brain plasticity of the sensorimotor system in stroke patients using this new musical therapy approach. Two different longitudinal clinical protocols have been undertaken. The project will also benefit from the utilization of behavioural and spatiotemporal neuroimaging in order to evaluate the brain changes induced after the application of the different neurorehabilitation techniques. Three different techniques are used in order to evaluate sensorimotor reorganization and brain connectivity: electroencephalography (Event-related brain potentials and time-frequency analysis, ERD-ERS), Magnetic Resonance Imaging (MRI, functional and diffusion tensor imaging, DTI) and repeated Transcortical Magnetic Stimulation (rTMS). These data will provide information about the physiological mechanisms underlying the efficacy of MT and will be used to further improve new techniques of rehabilitation. We expect that the significant improvement in the functional use of the paretic arm in the patients will be accompanied by signs of neuroplastic reorganization at the sensorimotor cortex evidenced by the different neuroimaging techniques.
We are interested in understanding human memory function and its implementation in the brain. A current view in memory research holds that reactivation of facts and events is a key feature of how brain resolves the problem of maintaining, storing and retrieving memory events. Recent advances in neuroimaging techniques (fMRI, EEG, MEG) allows us directly testing this hypothesis as well as to further investigate the neural mechanisms sustaining it. Previous findings suggest that human hippocampus play a crucial role in coordinating brain information to be stored in the brain. This coordination brings up the possibility to associate, integrate and consolidate new information in long-term memory but also to reinstate it to flexibly manipulate it in our ongoing day life. Here, we attempt to study information reactivation as one of the fundamental aspects of human memory functioning. Our group combines data from behavioral and neuroimaging techniques on healthy population to characterize the neural mechanisms sustaining memory reactivation. This approach is also extended to neurological patients who suffer from medial temporal lobe impairment.