Increasing Brain Gamma Activity Improves Episodic Memory and Restores Cholinergic Dysfunction in Alzheimer's Disease

Alberto Benussi, Valentina Cantoni, Mario Grassi, Lucie Brechet, Christoph M Michel, Abhishek Datta, Chris Thomas, Stefano Gazzina, Maria Sofia Cotelli, Marta Bianchi, Enrico Premi, Yasmine Gadola, Maria Cotelli, Marta Pengo, Federica Perrone, Maria Scolaro, Silvana Archetti, Eino Solje, Alessandro Padovani, Alvaro Pascual-Leone, Barbara Borroni, Alberto Benussi, Valentina Cantoni, Mario Grassi, Lucie Brechet, Christoph M Michel, Abhishek Datta, Chris Thomas, Stefano Gazzina, Maria Sofia Cotelli, Marta Bianchi, Enrico Premi, Yasmine Gadola, Maria Cotelli, Marta Pengo, Federica Perrone, Maria Scolaro, Silvana Archetti, Eino Solje, Alessandro Padovani, Alvaro Pascual-Leone, Barbara Borroni

Abstract

Objective: This study aimed to assess whether non-invasive brain stimulation with transcranial alternating current stimulation at gamma-frequency (γ-tACS) applied over the precuneus can improve episodic memory and modulate cholinergic transmission by modulating cerebral rhythms in early Alzheimer's disease (AD).

Methods: In this randomized, double-blind, sham controlled, crossover study, 60 AD patients underwent a clinical and neurophysiological evaluation including assessment of episodic memory and cholinergic transmission pre and post 60 minutes treatment with γ-tACS targeting the precuneus or sham tACS. In a subset of 10 patients, EEG analysis and individualized modelling of electric field distribution were carried out. Predictors to γ-tACS efficacy were evaluated.

Results: We observed a significant improvement in the Rey Auditory Verbal Learning (RAVL) test immediate recall (p < 0.001) and delayed recall scores (p < 0.001) after γ-tACS but not after sham tACS. Face-name associations scores improved with γ-tACS (p < 0.001) but not after sham tACS. Short latency afferent inhibition, an indirect measure of cholinergic transmission, increased only after γ-tACS (p < 0.001). ApoE genotype and baseline cognitive impairment were the best predictors of response to γ-tACS. Clinical improvement correlated with the increase in gamma frequencies in posterior regions and with the amount of predicted electric field distribution in the precuneus.

Interpretation: Precuneus γ-tACS, able to increase γ-power activity on the posterior brain regions, showed a significant improvement of episodic memory performances, along with restoration of intracortical excitability measures of cholinergic transmission. Response to γ-tACS was dependent on genetic factors and disease stage. ANN NEUROL 2022;92:322-334.

Trial registration: ClinicalTrials.gov NCT04842955.

Conflict of interest statement

A.B. and B.B. have pending patent on the use of non‐invasive brain stimulation to increase memory functions in patients with Alzheimer Disease.

© 2022 The Authors. Annals of Neurology published by Wiley Periodicals LLC on behalf of American Neurological Association.

Figures

FIGURE 1
FIGURE 1
Neuropsychological and neurophysiological scores pre and post sham or γ‐tACS. (A) Spaghetti plots of RAVL total recall, RAVL long delayed recall, FNAT scores. (B) Spaghetti plots of SAI measures. Legend: RAVL = Rey Auditory Verbal Learning test; FNAT = face–name associations task; tACS = transcranial alternating current stimulation; SAI = short‐latency afferent inhibition. *For FNAT, results are reported during stimulation.
FIGURE 2
FIGURE 2
Result of the EEG frequency analysis. Frequency bands: theta (3–6 Hz), alpha (6–12 Hz), beta (12–20 Hz), gamma (20–40 Hz). (A) Power maps pre and post sham stimulation. (B) Power maps pre and post γ‐tACS. (C) t‐Maps of the paired t‐test post vs. pre γ‐tACS. Blue areas indicate a power decrease after γ‐tACS, red areas a power increase. Significant effects at p < 0.05 were found on electrodes F3, T3, and T4 for theta (decrease after γ‐tACS), on electrodes P3, T5, T6, and O2 for beta (increase after γ‐tACS), and on electrodes T4 and O2 for gamma. No effect was found in the alpha band after γ‐tACS and no effect was found on any bands when comparing pre vs. post sham stimulation. Legend: EEG = electroencephalography; tACS = transcranial alternating current stimulation.

References

    1. Cummings J, Lee G, Ritter A, et al. Alzheimer's disease drug development pipeline: 2020. Alzheimer's Dement. Transl Res Clin Interv 2020;6:e12050.
    1. Hampel H, Mesulam MM, Cuello AC, et al. The cholinergic system in the pathophysiology and treatment of Alzheimer's disease. Brain 2018;141:1917–1933.
    1. Sevigny J, Chiao P, Bussière T, et al. The antibody aducanumab reduces Aβ plaques in Alzheimer's disease [internet]. Nature 2016;537:50–56. Available from: 10.1038/nature19323.
    1. FDA Grants Accelerated Approval for Alzheimer's Drug [Internet] . 2021. [cited 2021 Jul 6 ] Available from:
    1. Koenig T, Prichep L, Dierks T, et al. Decreased EEG synchronization in Alzheimer's disease and mild cognitive impairment [internet]. Neurobiol Aging 2005;26:165–171.[cited 2019 Oct 9 ] Available from:. .
    1. Babiloni C, Lizio R, Marzano N, et al. Brain neural synchronization and functional coupling in Alzheimer's disease as revealed by resting state EEG rhythms [internet]. Int J Psychophysiol 2016;103:88–102. Available from. 10.1016/j.ijpsycho.2015.02.008.
    1. Iaccarino HF, Singer AC, Martorell AJ, et al. Gamma frequency entrainment attenuates amyloid load and modifies microglia [internet]. Nature 2016;540:230–235. Available from. 10.1038/nature20587.
    1. Martorell AJ, Paulson AL, Suk H, et al. Multi‐sensory gamma stimulation ameliorates Alzheimer's‐associated pathology and improves cognition. [internet]. Cell 2019;177:256–271.e22. Available from. 10.1016/j.cell.2019.02.014.
    1. Adaikkan C, Middleton SJ, Marco A, et al. Gamma entrainment binds higher‐order brain regions and offers neuroprotection [internet]. Neuron 2019;102:1–15. Available from. .
    1. Herrmann CS, Murray MM, Ionta S, et al. Shaping intrinsic neural oscillations with periodic stimulation. J Neurosci 2016;36:5328–5337.
    1. Antal A, Paulus W. Transcranial alternating current stimulation (tACS). Front Hum Neurosci 2013;7:1–4.
    1. Fröhlich F, Sellers KK, Cordle AL. Targeting the neurophysiology of cognitive systems with transcranial alternating current stimulation. Expert Rev Neurother 2014;15:145–167.
    1. Vosskuhl J, Strüber D, Herrmann CS. Non‐invasive brain stimulation: a paradigm shift in understanding brain oscillations. Front Hum Neurosci 2018;12:1–19.
    1. Herrmann CS, Rach S, Neuling T, Strüber D. Transcranial alternating current stimulation: a review of the underlying mechanisms and modulation of cognitive processes. [Internet]. Front Hum Neurosci 2013;7:279. Available from. .
    1. Bréchet L, Yu W, Biagi MC, et al. Patient‐tailored, home‐based non‐invasive brain stimulation for memory deficits in dementia due to Alzheimer's disease. Front Neurol 2021;12:1–12.
    1. Benussi A, Cantoni V, Cotelli MS, et al. Exposure to gamma tACS in Alzheimer's disease: a randomized, double‐blind, sham‐controlled, crossover, pilot study [internet]. Brain Stimul 2021;14:531‐540. .
    1. Corder EH, Saunders AM, Strittmatter WJ, et al. Gene dose of apolipoprotein E type 4 allele and the risk of Alzheimer's disease in late onset families. [internet]. Science 1993;261:921–923. Available from. .
    1. Riddle J, McPherson T, Atkins AK, et al. Brain‐derived neurotrophic factor (BDNF) polymorphism may influence the efficacy of tACS to modulate neural oscillations [internet]. Brain Stimul 2020;13:998–999. 10.1016/j.brs.2020.04.012.
    1. Guerra A, Asci F, Zampogna A, et al. Gamma‐transcranial alternating current stimulation and theta‐burst stimulation: inter‐subject variability and the role of BDNF [internet]. Clin Neurophysiol 2020;131:2691–2699. 10.1016/j.clinph.2020.08.017.
    1. Jack CR, Bennett DA, Blennow K, et al. NIA‐AA research framework: toward a biological definition of Alzheimer's disease [Internet]. Alzheimers Dement 2018;14:535–562.Available from. .
    1. Benussi A, Dell'Era V, Cantoni V, et al. TMS for staging and predicting functional decline in frontotemporal dementia. [Internet]. Brain Stimul 2020;13:386–392. Available from:. .
    1. Nucci M, Mapelli D, Mondini S. Cognitive reserve index questionnaire (CRIq): a new instrument for measuring cognitive reserve. Aging Clin Exp Res 2012;24:218–226.
    1. Padovani A, Benussi A, Cantoni V, et al. Diagnosis of mild cognitive impairment due to Alzheimer's disease with transcranial magnetic stimulation. [Internet] J Alzheimers Dis 2018;65:221–230. Available from. .
    1. Kasten FH, Dowsett J, Herrmann CS. Sustained aftereffect of α‐tACS lasts up to 70 min after stimulation. Front Hum Neurosci 2016;10:1–9.
    1. Rey A. L'Examen Clinique en Psychologie [clinical examination in psychology]. 1964.
    1. Rentz DM, Amariglio RE, Becker JA, et al. Face‐name associative memory performance is related to amyloid burden in normal elderly [internet]. Neuropsychologia 2011;49:2776–2783. Available from. 10.1016/j.neuropsychologia.2011.06.006.
    1. Jung TP, Makeig S, Humphries C, et al. Removing electroencephalographic artifacts by blind source separation. Psychophysiology 2000;37:163–178.
    1. Benussi A, Cosseddu M, Filareto I, et al. Impaired long‐term potentiation‐like cortical plasticity in presymptomatic genetic frontotemporal dementia. [internet]. Ann Neurol 2016;80:472–476. 10.1002/ana.24731.
    1. Benussi A, Grassi M, Palluzzi F, et al. Classification accuracy of transcranial magnetic stimulation for the diagnosis of neurodegenerative dementias. [internet]. Ann Neurol 2020;87:394–404. Available from. .
    1. Tokimura H, Di Lazzaro V, Tokimura Y, et al. Short latency inhibition of human hand motor cortex by somatosensory input from the hand. [internet]. J Physiol 2000;523:503–513. 10.1111/j.1469-7793.2000.t01-1-00503.x.
    1. Mehta AR, Pogosyan A, Brown P, Brittain JS. Montage matters: the influence of transcranial alternating current stimulation on human physiological tremor [internet]. Brain Stimul 2015;8:260–268. 10.1016/j.brs.2014.11.003.
    1. Fernández‐Ruiz A, Oliva A, Soula M, et al. Gamma rhythm communication between entorhinal cortex and dentate gyrus neuronal assemblies. Science 2021;372:eabf3119.
    1. Yamamoto J, Suh J, Takeuchi D, Tonegawa S. Successful execution of working memory linked to synchronized high‐frequency gamma oscillations [internet]. Cell 2014;157:845–857. 10.1016/j.cell.2014.04.009.
    1. Scott L, Feng J, Kiss T, et al. Age‐dependent disruption in hippocampal theta oscillation in amyloid‐β overproducing transgenic mice [internet]. Neurobiol Aging 2012;33:1481.e13–1481.e23. 10.1016/j.neurobiolaging.2011.12.010.
    1. Başar E, Emek‐Savaş DD, Güntekin B, Yener GG. Delay of cognitive gamma responses in Alzheimer's disease. NeuroImage Clin 2016;11:106–115.
    1. Grunwald M, Busse F, Hensel A, et al. Correlation between cortical θ activity and hippocampal volumes in health, mild cognitive impairment, and mild dementia. J Clin Neurophysiol 2001;18:178–184.
    1. Naro A, Corallo F, De Salvo S, et al. Promising role of Neuromodulation in predicting the progression of mild cognitive impairment to dementia. J Alzheimers Dis 2016;53:1375–1388.
    1. Xing Y, Wei P, Wang C, et al. TRanscranial AlterNating current stimulation FOR patients with mild Alzheimer's disease (TRANSFORM‐AD study): protocol for a randomized controlled clinical trial. Alzheimer's Dement Transl Res Clin Interv 2020;6:1–8.
    1. Kim J, Kim H, Jeong H, et al. tACS as a promising therapeutic option for improving cognitive function in mild cognitive impairment: a direct comparison between tACS and tDCS [internet]. J Psychiatr Res 2021;141:248–256. 10.1016/j.jpsychires.2021.07.012.
    1. Johnson L, Alekseichuk I, Krieg J, et al. Dose‐dependent effects of transcranial alternating current stimulation on spike timing in awake nonhuman primates [Internet]. Sci.Adv 2020;6:eaaz2747. Available from. 10.1126/sciadv.aaz2747.
    1. Beliaeva V, Polania R. Can low‐intensity tACS genuinely entrain neural activity in vivo? Brain Stimul 2020;13:1796–1799.
    1. Amat‐Foraster M, Leiser SC, Herrik KF, et al. The 5‐HT6 receptor antagonist idalopirdine potentiates the effects of donepezil on gamma oscillations in the frontal cortex of anesthetized and awake rats without affecting sleep‐wake architecture [internet]. Neuropharmacology 2017;113:45–59. 10.1016/j.neuropharm.2016.09.017.
    1. Spencer JP, Middleton LJ, Davies CH. Investigation into the efficacy of the acetylcholinesterase inhibitor, donepezil, and novel procognitive agents to induce gamma oscillations in rat hippocampal slices [internet]. Neuropharmacology 2010;59:437–443. 10.1016/j.neuropharm.2010.06.005.
    1. Babiloni C, Del Percio C, Bordet R, et al. Effects of acetylcholinesterase inhibitors and memantine on resting‐state electroencephalographic rhythms in Alzheimer's disease patients [internet]. Clin Neurophysiol 2013;124:837–850. 10.1016/j.clinph.2012.09.017.
    1. Cavanna AE, Trimble MR. The precuneus: a review of its functional anatomy and behavioural correlates. Brain 2006;129:564–583.
    1. Woods AJ, Antal A, Bikson M, et al. A technical guide to tDCS, and related non‐invasive brain stimulation tools [internet]. Clin Neurophysiol 2016;127:1031–1048. Available from. .
    1. Inukai Y, Saito K, Sasaki R, et al. Comparison of three non‐invasive transcranial electrical stimulation methods for increasing cortical excitability. [internet]. Front Hum Neurosci 2016;10:668. Available from. .
    1. Sivaramakrishnan A, Datta A, Bikson M, Madhavan S. Remotely supervised transcranial direct current stimulation: a feasibility study for amyotrophic lateral sclerosis. NeuroRehabilitation 2019;45:369–378.
    1. Charvet LE, Shaw MT, Bikson M, et al. Supervised transcranial direct current stimulation (tDCS) at home: a guide for clinical research and practice [internet]. Brain Stimul 2020;13:686–693. Available from. 10.1016/j.brs.2020.02.011.
    1. Huo L, Li R, Wang P, et al. The default mode network supports episodic memory in cognitively unimpaired elderly individuals: different contributions to immediate recall and delayed recall. Front Aging Neurosci 2018;10:1–10.
    1. Whitfield‐Gabrieli S, Ford JM. Default mode network activity and connectivity in psychopathology. Annu Rev Clin Psychol 2012;8:49–76.
    1. Small GW, Ercoli LM, Silverman DHS, et al. Cerebral metabolic and cognitive decline in persons at genetic risk for Alzheimer's disease. Proc Natl Acad Sci U S A 2000;97:6037–6042.
    1. Lundstrom BN, Petersson KM, Andersson J, et al. Isolating the retrieval of imagined pictures during episodic memory: activation of the left precuneus and left prefrontal cortex. Neuroimage 2003;20:1934–1943.
    1. Wagner AD, Shannon BJ, Kahn I, Buckner RL. Parietal lobe contributions to episodic memory retrieval. Trends Cogn Sci 2005;9:445–453.
    1. Koch G, Bonnì S, Pellicciari MC, et al. Transcranial magnetic stimulation of the precuneus enhances memory and neural activity in prodromal Alzheimer's disease [internet]. Neuroimage 2018;169:302–311. 10.1016/j.neuroimage.2017.12.048.
    1. Kirwan CB, Stark CEL. Medial temporal lobe activation during encoding and retrieval of novel face‐name pairs. Hippocampus 2004;14:919–930.
    1. Ali MM, Sellers KK, Fröhlich F. Transcranial alternating current stimulation modulates large‐scale cortical network activity by network resonance. J Neurosci 2013;33:11262–11275.
    1. Meng A, Kaiser M, de Graaf TA, et al. Transcranial alternating current stimulation at theta frequency to left parietal cortex impairs associative, but not perceptual, memory encoding [internet]. Neurobiol. Learn. Mem 2021;182:107444. 10.1016/j.nlm.2021.107444.
    1. Freedberg M, Reeves JA, Toader AC, et al. Persistent enhancement of hippocampal network connectivity by parietal rTMS is reproducible. eNeuro 2019;6:1–13.
    1. Cacabelos R. Pharmacogenetic considerations when prescribing cholinesterase inhibitors for the treatment of Alzheimer's disease [internet]. Expert Opin Drug Metab Toxicol 2020;16:673–701. 10.1080/17425255.2020.1779700.
    1. Verghese PB, Castellano JM, Holtzman DM. Apolipoprotein E in Alzheimer's disease and other neurological disorders [internet]. Lancet Neurol 2011;10:241–252. 10.1016/S1474-4422(10)70325-2.
    1. Andrieu S, Coley N, Lovestone S, et al. Prevention of sporadic Alzheimer's disease: lessons learned from clinical trials and future directions [internet]. Lancet Neurol 2015;14:926–944. Available from. .
    1. Wright A, Hannon J, Hegedus EJ, Kavchak AE. Clinimetrics corner: a closer look at the minimal clinically important difference (MCID). J Man Manip Ther 2012;20:160–166.
    1. Honnorat J, Antoine J‐C, Saiz A, et al. Cerebellar ataxia with anti‐glutamic acid decarboxylase antibodies: study of 14 patients. [internet]. Arch Neurol 2001;58:225–230. Available from. .

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