[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"trial:NCT07208318":3,"trial-entities:NCT07208318":97,"trial-summary:NCT07208318":100},{"id":4,"nct_id":4,"org_study_id":5,"brief_title":6,"official_title":7,"overall_status":8,"completion_date":9,"status_verified_date":10,"last_update_date":11,"start_date":12,"sponsor_name":13,"lead_sponsor_class":14,"has_dmc":15,"brief_summary":16,"detailed_description":17,"conditions":18,"keywords":22,"study_type":23,"primary_purpose":24,"phases":25,"enrollment_info":27,"interventions":30,"primary_outcomes":38,"secondary_outcomes":49,"sex":50,"minimum_age":51,"maximum_age":52,"healthy_volunteers":53,"eligibility_criteria":54,"std_ages":72,"locations":75,"central_contacts":91,"overall_officials":94,"references":95,"see_also_links":96},"NCT07208318","4230E_2","Restructuring the Alpha-Gamma Code in Aging Vision","Rescuing Visual Perception in Aging Adults by Restructuring the Alpha-Gamma Neural Code","RECRUITING","2030-08-31","2026-07","2026-07-16","2026-04-02","Boston University Charles River Campus","OTHER",false,"Tests whether age-related visual deficits arise from disrupted alpha-gamma coupling in visual cortex (V1) and MT. Uses fMRI, source-resolved HD-EEG, and personalized complex-waveform HD-tACS to (1) quantify aging effects on phase-amplitude coupling, (2) drive PAC into a preferred \"gamma-at-alpha-troughs\" state, and (3) bidirectionally change perception by aligning gamma to alpha troughs vs peaks. Two five-day, double-blind, sham-controlled studies (n=120 each) target contrast sensitivity (V1) and 3D shape-from-motion (MT), aiming for mechanistic insight and remediation in older adults with implications for ADRD.","The project probes a causal account of age-related perceptual decline by focusing on alpha-gamma phase-amplitude coupling (PAC) in early visual cortex and area MT. The central hypothesis is that aging alters both the magnitude and phase structure of alpha-gamma interactions, degrading visual performance; restoring a preferred configuration-gamma power nested at alpha troughs-should improve perception.\n\nMultimodal methods combine structural\u002Ffunctional MRI, high-density EEG with source reconstruction, and individualized complex-waveform HD-tACS tuned to each participant's neuroanatomy and oscillatory frequencies. Three questions drive the work: (i) Do age-related deficits track changes in alpha-gamma PAC magnitude\u002Fphase? (ii) Can frequency-coupled HD-tACS enforce the preferred PAC configuration and enhance perception, especially in more impaired older adults? (iii) Is perception bidirectionally controllable by placing gamma at alpha troughs (facilitation) versus peaks (disruption)?\n\nTwo specific aims implement matched, five-day, within-subjects, double-blind, sham-controlled experiments with 120 participants each. Aim 1 targets early visual cortex to test whether contrast sensitivity deficits scale with age, spatial frequency, and noise, and whether personalized HD-tACS can optimize PAC to improve contrast perception. Aim 2 targets MT to test whether 3D shape-from-motion (parallax) judgments decline with age as a function of surface-point lifetime and simulated depth, and whether trough- versus peak-aligned stimulation can restructure PAC to enhance motion-based shape perception. Outcomes will establish mechanistic links between PAC and visual aging and evaluate a noninvasive, personalized intervention path relevant to age-related decline and ADRD.",[19,20,21],"Aging","Visual Perception","Noninvasive Brain Stimulation",[],"INTERVENTIONAL","BASIC_SCIENCE",[26],"EARLY_PHASE1",{"count":28,"type":29},240,"ESTIMATED",[31],{"type":32,"name":33,"description":34,"armGroupLabels":35},"DEVICE","High definition transcranial electrical current stimulation","Low-intensity and safe, noninvasive application of electrical current to the human scalp with the goal of gradually modulating levels of neuronal excitability.",[36,37],"active stimulation","sham stimulation",[39,43,46],{"measure":40,"description":41,"timeFrame":42},"contrast sensitivity","Orientation identification task","Baseline (pre-stimulation) and immediately post-stimulation, collected on each of the 5 study days.",{"measure":44,"description":45,"timeFrame":42},"3D structural-from-motion","surface point lifetime (unlimited, 12 and 2 successive views) on 3D discrimination task",{"measure":47,"description":48,"timeFrame":42},"phase-amplitude coupling","alpha phase, gamma amplitude coupling (magnitude of coherency)",[],"ALL","18 Years",null,true,{"inclusion":55,"exclusion":58,"raw_text":71},[56,57],"18+ years of age or older","normal or corrected-to-normal visual acuity, color vision, and stereo vision",[59,60,61,62,63,64,65,66,67,68,69,70],"not pregnant,","no metal implants in head,","no implanted electronic devices,","no history of neurological problems or head injury,","no skin sensitivity,","no claustrophobia,","no dementia (normal Mini Mental State Examination between 24-30; Montreal Cognitive Assessment \\> 25)","no depression (normal Beck Depression Inventory II \\\u003C13; Geriatric Depression Scale \\\u003C 10)","no ophthalmological diseases (e.g., strabismus, glaucoma, cataract, macular degeneration)","no history of psychosis","no cognitive deficits (MMSE score\\>24; MoCA\\>25)","cannot be taking any psychoactive medication.","Inclusion Criteria:\n\n* 18+ years of age or older\n* normal or corrected-to-normal visual acuity, color vision, and stereo vision\n\nExclusion Criteria:\n\n* not pregnant,\n* no metal implants in head,\n* no implanted electronic devices,\n* no history of neurological problems or head injury,\n* no skin sensitivity,\n* no claustrophobia,\n* no dementia (normal Mini Mental State Examination between 24-30; Montreal Cognitive Assessment \\> 25)\n* no depression (normal Beck Depression Inventory II \\\u003C13; Geriatric Depression Scale \\\u003C 10)\n* no ophthalmological diseases (e.g., strabismus, glaucoma, cataract, macular degeneration)\n* no history of psychosis\n* no cognitive deficits (MMSE score\\>24; MoCA\\>25)\n* cannot be taking any psychoactive medication.",[73,74],"ADULT","OLDER_ADULT",[76],{"facility":77,"status":8,"city":78,"state":79,"zip":80,"country":81,"contacts":82,"geoPoint":88},"111 Cummington Mall, Boston University","Boston","Massachusetts","02215","United States",[83],{"name":84,"role":85,"phone":86,"email":87},"Robert Reinhart, PhD","CONTACT","617-353-9481","rmgr@bu.edu",{"lat":89,"lon":90},42.35843,-71.05977,[92],{"name":84,"role":85,"phone":93,"email":87},"(617) 353-9481",[],[],[],{"nct_id":4,"conditions":98,"biomarkers":99},[19,20],[],{"nct_id":4,"found":53,"summary":101,"prompt_version":110},{"design":102,"status":103,"heading":6,"summary":104,"follow_up":105,"word_count":106,"commitments":107,"compensation":108,"drugs_mentioned":109},"This is an interventional study with a planned enrollment of 240 participants. It involves two separate five-day, double-blind, sham-controlled studies.","completed","This study is exploring how our brains process vision as we age and whether a technique called high definition transcranial electrical current stimulation (HD-tACS) can improve age-related vision changes. HD-tACS is a low-intensity, safe, noninvasive method that uses electrical currents applied to the scalp to gently adjust brain activity. Researchers want to see if changes in brain wave patterns, specifically alpha-gamma coupling, contribute to vision problems in older adults. The study aims to use HD-tACS to restore these brain wave patterns to a preferred state, hoping to improve your vision. We are looking for 240 participants aged 18 and older with normal or corrected-to-normal vision. The study will measure changes in your ability to see contrast and 3D shapes.","Your vision will be measured at baseline (before stimulation) and immediately after stimulation on each of the five study days.",119,"You would participate in two five-day studies. During each study day, your vision will be tested before and immediately after receiving the stimulation.","Not stated in the trial record.",[33],"v2"]