Human Thalamus in Propagation of Temporal Lobe Seizures and Memory Formation
- Conditions
- Epilepsy
- Registration Number
- NCT07226908
- Lead Sponsor
- Stanford University
- Brief Summary
The goal of the study is to examine how two key subregions of the human thalamus (ANT and PLV) are connected with other brain structures (Aim 1), how seizures involve the two thalamic subregions differently and how the map of cortico-thalamic ictal propagation matches the intrinsic connectivity maps identified in the same individuals (Aim 2), and the effect of ANT and PLV stimulations on memory formation (Aim 3).
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- ENROLLING_BY_INVITATION
- Sex
- All
- Target Recruitment
- 100
- No medical or surgical contraindication to electrode implantation
- Patient capable of understanding the scope of our project or signing informed consent independently
- Unable to provide informed consent
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- SINGLE_GROUP
- Primary Outcome Measures
Name Time Method Cerebro-cerebral evoked potentials During experiment up to 2 weeks To map thalamocortical and corticothalamic causal effective connectivity, the study team will use the well-known method of repeated single electrical pulse stimulation with intracranial EEG. Study team will measure the amplitude and timing to first peak of cerebro-cerebral evoked potentials (CCEPs).
fMRI BOLD activity During experiment up to 2 weeks To map thalamocortical and corticothalamic functional connectivity, he study team will obtain 8 runs of 6mins resting state fMRIs. Study team will measure the correlation of BOLD activity across voxels of interest.
Epileptogenicity Index (EI) During experiment up to 2 weeks The study team will identify seizure onset zones (SOZs) using the measure of Epileptogenicity Index (EI) applied to data collected through intracranial EEG, and will label the SOZs as medial temporal lobe epilepsy (mTLE) versus nonmedial TLEs.
Seizure propagation During experiment up to 2 weeks Seizure propagation to ANT and PLV will be examined through intracranial EEG data within individuals by measuring EI and the propagation latencies from SOZ to ANT and PLV recording sites will be noted.
Coordinated activity across HPC and ANT During experiment up to 2 weeks Successful memory encoding is associated with coordinated activity across hippocampus (HPC) and ANT (i.e., high frequency activity in ANT locked to the phase of hippocampal theta). Using intracranial EEG data, the study team will follow traditional analyses of changes in power in the canonical EEG bands (e.g., 3-7 Hz, theta band, 40-150 Hz, high gamma, etc.) as well as computationally derived aperiodic features of the signal \[i.e., using the fitting oscillations \& one over f (FOOOF) function\]. Response onset latency of neural activity will determine with simultaneous recordings across HPC, ANT, and PLV how each ROI is engaged in time during a given experimental condition (i.e., encoding trials later recalled and trials not later recalled). We will also use validated methods of phase amplitude coupling (PAC) and intersite phase coherence (ISPC) to quantify cross regional relationships.
Cognitive task performance During experiment up to 2 weeks In total, each patient will be asked to encode 200 words across the 5 sessions.
- Secondary Outcome Measures
Name Time Method
Trial Locations
- Locations (1)
Stanford Hospital
🇺🇸Stanford, California, United States
Stanford Hospital🇺🇸Stanford, California, United States