{"count":5,"limit":50,"offset":0,"edits":[{"id":4973,"actor_id":null,"entity_type":"hypothesis","entity_id":"h-var-b7e4505525","action":"update","diff_json":{"after":"376c6f823ef164848811131013812e8da1f81e32c1b0f7fdcecd16033681ae27","before":"0bcc1a904cca52ecde8e569b49bc07c072fa2fa74735f452cb7a2151ae3fa3d6"},"change_reason":"enrich EC-II vulnerability hypotheses with evidence addenda","created_at":"2026-04-21T02:54:50.595930+00:00"},{"id":4974,"actor_id":null,"entity_type":"hypothesis","entity_id":"h-var-b7e4505525","action":"update","diff_json":{"after":"This hypothesis proposes using closed-loop transcranial focused ultrasound (tFUS) to selectively activate somatostatin-positive (SST) interneurons in entorhinal cortex layer II as an upstream intervention to restore hippocampal gamma oscillations in Alzheimer's disease. The approach leverages mechanosensitive ion channel activation (PIEZO1/TREK-1) in EC-II SST interneurons through precisely timed ultrasonic stimulation, triggering SST release and creating gamma-frequency entrainment at 30-80 Hz that propagates through the perforant path to re-establish hippocampal CA1 gamma dynamics. Unlike direct hippocampal targeting, this upstream intervention addresses the source of gamma disruption by restoring the entorhinal cortex's role as the primary gamma pacemaker for the hippocampal formation. The closed-loop system uses real-time EEG monitoring to detect endogenous gamma power in the entorhinal-hippocampal circuit, delivering ultrasound bursts only when gamma coherence falls below threshold levels, ensuring physiologically appropriate timing and preventing overstimulation. SST interneurons in EC layer II are strategically positioned to gate perforant path transmission through perisomatic inhibition of stellate cells, making them ideal targets for restoring the precise inhibitory timing required for gamma generation. The ultrasound-induced depolarization triggers calcium influx through mechanosensitive channels, activating calcium-dependent potassium channels and SST release, which binds to somatostatin receptors (SSTR1-5) creating a negative feedback loop that entrains gamma oscillations. This mechanism bypasses the direct targeting of damaged hippocampal PV interneurons while leveraging the entorhinal cortex's preserved capacity for gamma generation in early AD stages, offering a non-invasive approach to restore hippocampal-prefrontal synchrony and rescue memory function.\n\n## Evidence enrichment addendum: ecii-sst-tfus-perforant-gating\n\n        ### Mechanistic focus\n        SST interneuron activation, perforant-path gating, and hippocampal gamma restoration.\n\n\nThe shared evidence base for this EC layer II vulnerability family is now\nstronger than a generic \"entorhinal dysfunction\" claim. Neuropathology and\nsingle-cell evidence both place transentorhinal and entorhinal circuits at the\nfront of the Alzheimer cascade: Braak staging identified early neurofibrillary\nchange in these regions, modern tau-seeding work shows seeding activity can\nbegin in transentorhinal/entorhinal tissue before widespread cortical spread,\nand recent human cell-type profiling reports layer II entorhinal neurons as a\nselectively vulnerable population at the onset of AD neuropathology (PMID:\n39435008; PMID: 39803521). A 2023 review of entorhinal cortex dysfunction in AD\nalso links medial and lateral EC layer 2 output neurons to the perforant and\ntemporoammonic paths that feed dentate gyrus, CA3, and CA1, making EC-II a\nplausible upstream control point rather than a downstream bystander (PMID:\n36513524). In an EC-tau mouse model, tau pathology was sufficient to produce\nexcitatory neuron loss, degraded grid-cell tuning, altered network activity, and\nspatial memory deficits reminiscent of early AD (PMID: 28111080). The\nneuromodulation branch of this task is additionally supported by 40 Hz gamma\nentrainment studies: optogenetic or sensory gamma stimulation altered amyloid\nburden and microglial state in AD models (PMID: 27929004), and early feasibility\nclinical studies show that noninvasive gamma stimulation can entrain human\nneural activity with acceptable short-term tolerability while leaving efficacy\nas an open question (PMID: 34027028; PMID: 30155285).\n\nThe implication for SciDEX scoring is that EC-II hypotheses should be evaluated\non three separable axes: first, whether the proposed target maps to a layer II\ncell type or projection that is actually vulnerable in AD; second, whether the\nintervention can shift the network state without causing hyperexcitability,\nseizure risk, or nonspecific arousal; and third, whether the readout captures\nearly circuit rescue rather than only late global cognition. Strong support\nwould therefore require convergent biomarkers: tau or p-tau217 to confirm\ndisease stage, high-resolution structural or functional imaging of EC and\nhippocampal subfields, EEG/MEG evidence for theta-gamma coupling or gamma power\nchanges, and a behavioral assay sensitive to path integration, mnemonic\nseparation, or spatial remapping. Weak support would be any result that improves\na broad cognitive endpoint without demonstrating EC engagement, because such a\nsignal could come from attention, sleep, mood, or generalized cortical\nactivation rather than the specific layer II mechanism.\n\n\n        ### Hypothesis-specific interpretation\n        The strongest form of this hypothesis is that EC-II SST cells regulate dendritic integration in perforant-path recipient circuits, so closed-loop tFUS should be timed to deficient gamma/theta-gamma states rather than delivered tonically. The therapeutic objective is to restore information gating from EC into dentate gyrus and CA fields before pathological tau spread becomes self-propagating.\n\n        ### Validation path\n        Use closed-loop EEG or local field potential triggers, quantify perforant-path input-output gain, and track p-tau spread from EC to hippocampus alongside spatial navigation behavior.\n\n        ### Counterevidence and market caveats\n        SST activation can suppress dendritic integration too strongly; dose-finding must include hypoactivity and memory-encoding failure as adverse mechanistic endpoints. A reasonable Exchange price should increase only when\n        EC engagement, cell-type specificity, and disease-stage matching are\n        demonstrated together. The most informative near-term experiment is a\n        staged design that first confirms the circuit target in an ex vivo or\n        animal model, then tests a closed-loop intervention with blinded\n        oscillatory, pathology, and behavioral endpoints. This keeps the claim\n        falsifiable: failure to engage EC-II physiology, failure to alter tau or\n        amyloid-linked pathology, or benefit that disappears under sham-controlled\n        stimulation would all materially weaken the hypothesis.\n","before":"This hypothesis proposes using closed-loop transcranial focused ultrasound (tFUS) to selectively activate somatostatin-positive (SST) interneurons in entorhinal cortex layer II as an upstream intervention to restore hippocampal gamma oscillations in Alzheimer's disease. The approach leverages mechanosensitive ion channel activation (PIEZO1/TREK-1) in EC-II SST interneurons through precisely timed ultrasonic stimulation, triggering SST release and creating gamma-frequency entrainment at 30-80 Hz that propagates through the perforant path to re-establish hippocampal CA1 gamma dynamics. Unlike direct hippocampal targeting, this upstream intervention addresses the source of gamma disruption by restoring the entorhinal cortex's role as the primary gamma pacemaker for the hippocampal formation. The closed-loop system uses real-time EEG monitoring to detect endogenous gamma power in the entorhinal-hippocampal circuit, delivering ultrasound bursts only when gamma coherence falls below threshold levels, ensuring physiologically appropriate timing and preventing overstimulation. SST interneurons in EC layer II are strategically positioned to gate perforant path transmission through perisomatic inhibition of stellate cells, making them ideal targets for restoring the precise inhibitory timing required for gamma generation. The ultrasound-induced depolarization triggers calcium influx through mechanosensitive channels, activating calcium-dependent potassium channels and SST release, which binds to somatostatin receptors (SSTR1-5) creating a negative feedback loop that entrains gamma oscillations. This mechanism bypasses the direct targeting of damaged hippocampal PV interneurons while leveraging the entorhinal cortex's preserved capacity for gamma generation in early AD stages, offering a non-invasive approach to restore hippocampal-prefrontal synchrony and rescue memory function."},"change_reason":"enrich EC-II vulnerability hypotheses with evidence addenda","created_at":"2026-04-21T02:54:50.595930+00:00"},{"id":4975,"actor_id":null,"entity_type":"hypothesis","entity_id":"h-var-b7e4505525","action":"update","diff_json":{"after":0.78,"before":0.9},"change_reason":"enrich EC-II vulnerability hypotheses with evidence addenda","created_at":"2026-04-21T02:54:50.595930+00:00"},{"id":4976,"actor_id":null,"entity_type":"hypothesis","entity_id":"h-var-b7e4505525","action":"update","diff_json":{"after":"2026-04-20 19:54:50.595930-07:00","before":"2026-04-20 06:26:26.993470-07:00"},"change_reason":"enrich EC-II vulnerability hypotheses with evidence addenda","created_at":"2026-04-21T02:54:50.595930+00:00"},{"id":4977,"actor_id":null,"entity_type":"hypothesis","entity_id":"h-var-b7e4505525","action":"update","diff_json":{"after":"'-5':239 '-80':94 '2':421 '2023':406 '27929004':517 '28111080':486 '30':93 '30155285':549 '34027028':547 '36513524':452 '39435008':402 '39803521':404 '40':497 'accept':534 'activ':40,70,224,304,368,476,532,701,814 'actual':584 'ad':273,399,413,484,514,587 'addendum':293 'addit':494 'address':117 'advers':833 'alongsid':805 'also':414 'alter':474,507,910 'alzheim':24,61,350 'amyloid':508,914 'amyloid-link':913 'anim':880 'approach':65,280 'appropri':174 'arous':604 'assay':662 'attent':695 'axe':567 'base':316 'becom':771 'begin':370 'behavior':661,808,894 'benefit':918 'bind':234 'biomark':626 'blind':890 'braak':352 'branch':489 'broad':681 'burden':509 'burst':163 'bypass':251 'bystand':450 'ca':765 'ca1':107,436 'ca3':434 'calcium':219,226 'calcium-depend':225 'capac':267 'captur':610 'cascad':351 'caus':598 'caveat':812 'cell':198,337,382,472,578,725,847 'cell-typ':381,846 'chang':357,658 'channel':69,223,229 'circuit':160,344,612,734,873 'claim':332,899 'clinic':521 'close':2,32,141,737,779,886 'closed-loop':1,31,140,736,778,885 'cognit':619,682 'coher':167 'come':693 'confirm':633,871 'control':444,924 'converg':625 'cortex':48,127,264,410 'cortic':376,700 'could':692 'counterevid':809 'coupl':654 'creat':87,240 'damag':256 'defici':744 'deficit':480 'degrad':469 'deliv':161,749 'demonstr':685,856 'dendrit':727,817 'dentat':432,762 'depend':227 'depolar':217 'design':868 'detect':151 'direct':111,253 'disappear':920 'diseas':26,63,634,852 'disease-stag':851 'disrupt':122 'dose':822 'dose-find':821 'downstream':449 'dynam':109 'dysfunct':331,411 'earli':272,355,483,519,611 'ec':9,74,182,319,419,439,456,558,644,686,722,760,802,844,905 'ec-ii':8,73,438,557,721,904 'ec-tau':455 'ecii':295 'ecii-sst-tfus-perforant-g':294 'eeg':148,781 'eeg/meg':648 'efficaci':541 'encod':830 'endogen':152 'endpoint':683,835,895 'engag':687,845,903 'enrich':292 'ensur':172 'entorhin':47,126,158,263,330,343,388,409,934 'entorhinal-hippocamp':157,933 'entrain':91,246,500,529 'establish':105 'evalu':563 'evid':291,315,338,649 'ex':877 'exchang':838 'excitatori':466 'experi':864 'failur':831,901,908 'fall':168 'falsifi':900 'famili':323 'feasibl':520 'feed':431 'feedback':243 'field':766,784 'find':823 'first':568,870 'focus':5,35,301 'form':715 'format':138 'frequenc':90 'front':347 'function':290,641 'gain':794 'gamma':16,58,89,108,121,133,153,166,211,247,269,311,499,505,526,653,656,936 'gamma-frequ':88 'gamma/theta-gamma':745 'gate':22,189,299,308,758 'general':699 'generat':212,270 'generic':329 'global':618 'grid':471 'grid-cel':470 'gyrus':433,763 'high':637 'high-resolut':636 'hippocamp':15,57,106,112,137,159,257,284,310,646,935 'hippocampal-prefront':283 'hippocampus':804 'human':380,530 'hyperexcit':599 'hypoact':826 'hypothes':560 'hypothesi':28,710,718,931 'hypothesis-specif':709 'hz':95,498 'ideal':201 'identifi':354 'ii':10,50,75,184,321,387,440,559,577,707,723,906 'imag':642 'implic':551 'improv':679 'includ':825 'increas':841 'induc':216 'influx':220 'inform':757,860 'inhibit':195 'inhibitori':207 'input':792 'input-output':791 'integr':666,728,818 'interneuron':12,45,77,180,259,303,941 'interpret':712 'intervent':54,116,591,888 'invas':279 'ion':68 'keep':897 'late':617 'later':418 'layer':49,183,320,386,420,576,706 'leav':540 'level':171 'leverag':66,261 'link':415,915 'local':783 'loop':3,33,142,244,738,780,887 'loss':468 'make':199,437 'map':573 'market':811 'match':854 'materi':928 'mechan':250,708 'mechanist':300,834 'mechanosensit':67,222,942 'medial':416 'memori':289,479,829 'memory-encod':828 'microgli':511 'mnemon':667 'model':459,515,881 'modern':361 'monitor':149 'mood':697 'mous':458 'must':824 'navig':807 'near':862 'near-term':861 'negat':242 'network':475,595,938 'neural':531 'neurofibrillari':356 'neuromodul':488 'neuron':389,423,467 'neuropatholog':333,400 'non':278 'non-invas':277 'noninvas':525 'nonspecif':603 'object':753 'offer':275 'onset':397 'open':544 'optogenet':502 'oscil':17,59,248,937 'oscillatori':891 'output':422,793 'overstimul':178 'p':630,798 'p-tau':797 'p-tau217':629 'pacemak':134 'path':21,101,191,307,429,665,732,776,790 'patholog':461,768,892,916 'perfor':20,100,190,298,306,426,731,789 'perforant-path':305,730,788 'perisomat':194 'physiolog':173,907 'piezo1/trek-1':71 'place':340 'plausibl':442 'pmid':401,403,451,485,516,546,548 'point':445 'popul':394 'posit':43,187 'potassium':228 'potenti':785 'power':154,657 'precis':79,206 'prefront':285 'preserv':266 'prevent':177 'price':839 'primari':132 'produc':465 'profil':384 'project':581 'propag':97,774 'propos':29,571 'pv':258 'quantifi':787 'question':545 'rather':446,614,702,747 're':104 're-establish':103 'readout':609 'real':146 'real-tim':145 'reason':837 'recent':379 'receptor':237 'recipi':733 'region':360 'regul':726 'releas':85,232 'remap':671 'reminisc':481 'report':385 'requir':209,624 'rescu':288,613 'resolut':638 'restor':14,56,124,204,282,312,756 'result':677 'review':407 'risk':601 'role':129 'scidex':553 'score':554 'second':588 'seed':364,367 'seizur':600 'select':39,392 'self':773 'self-propag':772 'sensit':663 'sensori':504 'separ':566,668 'sham':923 'sham-control':922 'share':314 'shift':593 'short':536 'short-term':535 'show':366,523 'signal':691,943 'singl':336 'single-cel':335 'sleep':696 'somatostatin':42,236 'somatostatin-posit':41 'sourc':119 'spatial':478,670,806 'specif':705,711,849 'spread':377,770,800 'sst':11,44,76,84,179,231,296,302,724,813,932,940 'sstr1':238 'stage':274,353,635,853,867 'state':512,596,746 'stellat':197 'stimul':82,506,527,925 'strateg':186 'strong':620,820 'stronger':326 'strongest':714 'structur':639 'studi':501,522 'subfield':647 'suffici':463 'support':495,621,673 'suppress':816 'synchroni':286 'system':143 'target':7,113,202,254,572,874 'task':492 'tau':363,457,460,627,769,799,911 'tau-seed':362 'tau217':631 'temporoammon':428 'term':537,863 'test':883 'tfus':37,297,739 'therapeut':752 'therefor':623 'theta':652 'theta-gamma':651 'third':606 'three':565 'threshold':170 'time':80,147,175,208,742 'tissu':373 'togeth':857 'toler':538 'tonic':750 'track':796 'transcrani':4,34 'transentorhin':341 'transentorhinal/entorhinal':372 'transmiss':192 'trigger':83,218,786 'tune':473 'type':383,579,848 'ultrason':81 'ultrasound':6,36,162,215 'ultrasound-induc':214 'unlik':110 'upstream':19,53,115,443 'use':30,144,777 'valid':775 'via':18,939 'vivo':878 'vulner':322,393,585 'weak':672 'weaken':929 'whether':569,589,607 'widespread':375 'without':597,684 'work':365 'would':622,674,926","before":"'-5':239 '-80':94 '30':93 'activ':40,70,224 'ad':273 'address':117 'alzheim':24,61 'approach':65,280 'appropri':174 'bind':234 'burst':163 'bypass':251 'ca1':107 'calcium':219,226 'calcium-depend':225 'capac':267 'cell':198 'channel':69,223,229 'circuit':160 'close':2,32,141 'closed-loop':1,31,140 'coher':167 'cortex':48,127,264 'creat':87,240 'damag':256 'deliv':161 'depend':227 'depolar':217 'detect':151 'direct':111,253 'diseas':26,63 'disrupt':122 'dynam':109 'earli':272 'ec':9,74,182 'ec-ii':8,73 'eeg':148 'endogen':152 'ensur':172 'entorhin':47,126,158,263,293 'entorhinal-hippocamp':157,292 'entrain':91,246 'establish':105 'fall':168 'feedback':243 'focus':5,35 'format':138 'frequenc':90 'function':290 'gamma':16,58,89,108,121,133,153,166,211,247,269,295 'gamma-frequ':88 'gate':22,189 'generat':212,270 'hippocamp':15,57,106,112,137,159,257,284,294 'hippocampal-prefront':283 'hypothesi':28 'hz':95 'ideal':201 'ii':10,50,75,184 'induc':216 'influx':220 'inhibit':195 'inhibitori':207 'interneuron':12,45,77,180,259,300 'intervent':54,116 'invas':279 'ion':68 'layer':49,183 'level':171 'leverag':66,261 'loop':3,33,142,244 'make':199 'mechan':250 'mechanosensit':67,222,301 'memori':289 'monitor':149 'negat':242 'network':297 'non':278 'non-invas':277 'offer':275 'oscil':17,59,248,296 'overstimul':178 'pacemak':134 'path':21,101,191 'perfor':20,100,190 'perisomat':194 'physiolog':173 'piezo1/trek-1':71 'posit':43,187 'potassium':228 'power':154 'precis':79,206 'prefront':285 'preserv':266 'prevent':177 'primari':132 'propag':97 'propos':29 'pv':258 're':104 're-establish':103 'real':146 'real-tim':145 'receptor':237 'releas':85,232 'requir':209 'rescu':288 'restor':14,56,124,204,282 'role':129 'select':39 'signal':302 'somatostatin':42,236 'somatostatin-posit':41 'sourc':119 'sst':11,44,76,84,179,231,291,299 'sstr1':238 'stage':274 'stellat':197 'stimul':82 'strateg':186 'synchroni':286 'system':143 'target':7,113,202,254 'tfus':37 'threshold':170 'time':80,147,175,208 'transcrani':4,34 'transmiss':192 'trigger':83,218 'ultrason':81 'ultrasound':6,36,162,215 'ultrasound-induc':214 'unlik':110 'upstream':19,53,115 'use':30,144 'via':18,298"},"change_reason":"enrich EC-II vulnerability hypotheses with evidence addenda","created_at":"2026-04-21T02:54:50.595930+00:00"}]}