Clinical Research Directory

Spatial Scene Recognition Memory in Epilepsy Surgery

This study investigates the anatomical and physiological basis of spatial scene recognition memory in patients with temporal lobe epilepsy and temporal lobe lesions. Standard neuropsychological tests are insensitive to important memory deficits experienced by patients, particularly in spatial/scene memory, recollective experience, and familiarity processing. Using a validated virtual tour paradigm, the study examines how familiarity-based recognition and recall of spatial scenes relate to specific brain structures. In Aim I, a large cohort of patients with varied temporal lobe lesions at Emory University undergoes the virtual tour task with voxel-based lesion-symptom mapping to localize necessary brain regions. In Aim II, scalp event-related potentials and eye tracking in healthy participants at UC Davis characterize the temporal dynamics and lateralization of scene recognition. In Aim III, intracranial EEG recordings (including local field potentials and single-unit activity) in epilepsy surgery patients at UC Davis determine the precise network dynamics underlying spatial scene familiarity and recall. The long-term goal is to improve the prediction and prevention of cognitive morbidity from epilepsy surgery by providing a more complete model of spatial recognition memory circuits.

Changes in Attentional Control After a Focal Seizure.

Epilepsy is frequently associated with cognitive and attentional disorders. Several studies have pointed out that there are modifications of brain activity in resting state during peri-ictal period in EEG and functional MRI. However, to date, no study has assessed the changes in attentional control after a seizure. The investigators hypothesize that a localized discharge is associated with a disorganization of the networks engaged in attentional control. In this regard, the investigators propose a prospective longitudinal study assessing the changes in attentional control after a focal seizure.

Integrating Metabolism, Connectivity, and Mesoscale Imaging at Ultra-high Field to Decipher Mechanisms of Resilience and Neurodegeneration in Neurological Diseases and Healthy Aging

The MESO7 study is a prospective observational research project designed to investigate the mechanisms of resilience and neurodegeneration in neurological diseases and healthy aging. It leverages advanced multiparametric brain and spinal cord imaging at high (3T) and ultra-high magnetic fields (7T) to assess structural, functional, metabolic, and mesoscale changes in the central nervous system (CNS). Particular emphasis is placed on sodium (23Na-MRI) and phosphorus (31P-MRI) imaging, along with layer-dependent brain connectivity analysis. The primary objective is to evaluate the impact of neuronal energy failure, measured via sodium concentration, on functional and structural reorganization in both healthy individuals and patients with various neurological conditions. Directed brain network models will be constructed from MRI data to quantify the connectivity strength (in- and out-degree) of cortical nodes. These connectivity metrics will be correlated with sodium concentrations to assess energy failure and its role in network reorganization. Longitudinal follow-up over two years is planned for subgroups with clinically progressive diseases. Secondary objectives include decoding metabolic, microstructural, and functional signatures of successful aging at the laminar level; characterizing disease-specific patterns of cortical and spinal microstructure associated with physical and cognitive dysfunction; describing longitudinal mesoscale and metabolic changes; and generating representative normative imaging datasets for the neuroscience community. The study plans to enroll a total of 540 patients across 9 neurological conditions:Multiple Sclerosis (MS), Neuromyelitis Optica Spectrum Disorders (NMOSD), MOG Antibody Disease (MOGAD), Alzheimer's disease, Parkinson's disease, Amyotrophic Lateral Sclerosis (ALS), temporal and non-temporal epilepsy, and mild traumatic brain injury (mTBI),in addition to 160 age- and sex-matched healthy controls, totaling 700 participants. Imaging and clinical assessments will be performed at the CEMEREM center at Timone University Hospital, AP-HM, Marseille, France. Each participant will undergo multiparametric brain and spinal cord MRI, including DTI, BOLD, MP2RAGE, SWI, quantitative sodium and phosphorus imaging, and functional assessments including neuropsychological testing, visual and motor function tests. Disease-specific assessments such as OCT, evoked potentials, and disability scores (e.g., EDSS for MS) will also be included when appropriate. The study is expected to improve understanding of CNS adaptation mechanisms and support the development of more accurate diagnostic and prognostic tools for neurodegenerative diseases

Transcranial Electrical Stimulation Targeting the Cerebellum for the Treatment of Refractory Temporal Lobe Epilepsy

Study the therapeutic effect and potential neural mechanisms of transcranial electrical stimulation targeting the cerebellum for the treatment of refractory temporal lobe epilepsy through MRI and EEG.

Intensive Preoperative Speech Rehabilitation in Drug-Resistant Temporal Epilepsy

Out of 30,000 new cases per year in France, 30% of epileptic patients are drug-resistant. Neurosurgery, which consists in resecting the epileptogenic zone, is the only chance of cure. In the case of temporal epilepsy of the language-dominant hemisphere (TLE), this procedure presents a high risk of increasing cognitive difficulties and may even be contraindicated for this reason alone. The difficulties found are impairments in lexical access (anomia) and verbal memory and affect more than 60% of patients . Preoperative cognitive rehabilitation could influence brain plasticity mechanisms but there are currently no recommendations on this topic. In this context, the investigators have developed a speech rehabilitation procedure specific to the needs of ELTPR patients. They rely on cognitive hypotheses explaining the disorders but also on models of rehabilitation-induced neural plasticity likely to improve cognitive reserve before surgery. The investigators hypothesize that preoperative cognitive language rehabilitation in ELTPR patients may decrease surgical risk and improve postoperative language prognosis. The primary objective is to demonstrate the protective efficacy of preoperative speech rehabilitation on language performance postoperatively.