Podcast Host: Dr. Andrew Huberman (Stanford Associate Professor - brain development, brain plasticity, and neural regeneration and repair fields)
- Youtube
- Lab Website
Podcast Guest: Dr. Nolan Williams (Stanford Assistant Professor - synergistic treatments with TMS and psychedelics for treatment of depression and mood disorders)
- Lab Website
*Subject Recruitment for Dr. William's Lab's Clinical Trial: A bounty on ResearchHub, paid in ResearchCoin, will be attached to incentivize recruitment for this clinical trial. If you apply to be a participant for the clinical trial for treatment of depression and other mood disorders (here on the right side of the page) and if approved you can post a comment with a screenshot of an approval email under the bounty to receive payment.
-Current price of ResearchCoin
Transcranial magnetic brain stimulation (TMS), namely to the dorsolateral pre-frontal cortex is a viable option to treat depression and mood disorders. Dr. Williams combines TMS with other more novel psychedelic treatments including ibogaine, psilocybin, cannabis, ketamine and DMT. Dr. Williams and Dr. Huberman discuss studies surrounding the efficacy, safety, and future of psychedelic research, as well as what some early mouse studies are pointing towards which is the ability to remove the psychological effects of the drug treatment but maintain the mental illness treating aspect of it. Additional discussions include, the topic of whether or not SSRI's are efficacious, the misconception of a chemical imbalance, ketamine, cannabis (THC/CBD balances),
Note: In the ethos of Open Science and transparent publication, this is a living document which will undergo continuous improvement. If you have suggestions, expansions, or corrections please feel free to comment in this thread and we will adjust the document as well as award some RSC for your help.
The following are bounties related to the topics of the podcast
“Moderate depression is about as disabling as having a heart attack, acutely having a heart attack.”
- Dr. Nolan Williams
“Severe depression is as disabling as having cancer without treatment and dying from a cancer without a treatment”
- Dr. Nolan Williams
Generally in emergency medicine - increases in symptom severity increase the amount of treatments/procedures attempted; in psychiatric disease, as the disease severity increases, the number of treatments go down on average!
Regions of the brain associated with emotion and the heart are connected.Dr. Williams comments on how heart rate modulation associated with transcranial magnetic brain stimulation (TMS) only explains a small percentage of mood shifts. Rather, there is likely “some parasympathetic process” that causes this to happen as change in mood due to TMS is acute and otherwise healthy persons experience similar reduction in heart rate following TMS. Drs. Huberman and Williams speak on the ability to ‘control’ your autonomic nervous system as a ‘hinge' related to the “lack of control over inner states" associated with depression. Of note, this sense of ‘how do we talk to ourselves’ is a keystone of cognitive behavioral therapy (CBT)--a profoundly powerful tool for persons with compulsive and debilitating depressions.
Figure 2-1: Map of spatial connections in the frontal-vegal pathway, demonstrating brain-heart connection. Image obtained from [2-1].
[2-1] Iseger et al. 2020. “A frontal-vagal network theory for Major Depressive Disorder: Implications for optimizing neuromodulation techniques”. Brain Stimulation. https://www.sciencedirect.com/science/article/pii/S1935861X19304139
Left DLPFC: Strokes on the brain that cause depression have been shown to interrupt the wiring to the left dorsolateral pre-frontal cortex [3-1].
Figure 3-1: Map of overlaid lesions from Grajny et al. 2016 showing locations of most frequent lesion distribution. Image obtained from [3-1].
[3-1] Grajny et al. 2016. “Depression Symptoms in Chronic Left Hemisphere Stroke Are Related to dorsolateral Prefrontal Cortex Damage”. The Journal of Neuropsychiatry and Clinical Neurosciences. https://neuro.psychiatryonline.org/doi/10.1176/appi.neuropsych.16010004
Why does left DLPFC slow the heart rate down and alleviate some symptoms of depression? Brachycardia occurs during fear (slowing down of heart rate) rather than speeding up
Do other ways of slowing the heart rate down alleviate depression?
Can we talk ourselves out of a depressive symptom or talk ourselves into a manic situation? Is this a structural thing or a thought-pattern thing?
Figure 4-1: Example of the original Stroop Test showing the prompts that participants may be given to analyze language processing and ‘rule switching’. Image obtained from [4-2].
[4-1] D. Spiegel. 2013. “Tranceformations: hypnosis in brain and body”. Depression and Anxiety. https://pubmed.ncbi.nlm.nih.gov/23423952/
[4-2] Baghdadi et al. 2021. “Neurocognitive Mechanisms of Attention”. Computational Models, Physiology, and Disease States. https://www.sciencedirect.com/topics/neuroscience/stroop-effect
The Stroop Task, shown in Figure 4-1, is like a rule-switching game which forces participants to suppress responses. Depressed people set ‘rules’ for the context of positivity in their lives such as ‘I dress poorly’ but have a hard time contradicting that rule (i.e. telling themselves they look good in the mirror feels like a lie to them). Something about the DLPFC gives flexibility to rules and this is measured indirectly by the Stroop Task.
[5-1] Cladder-Micus et al. 2018. “Mindfulness-based cognitive therapy for patients with chronic, treatment-resistant depression: A pragmatic randomized controlled trial”. Depression and Anxiety. https://pubmed.ncbi.nlm.nih.gov/30088834/
[5-2] Zhang et al. 2019. "Cognitive behavioral therapy for primary care depression and anxiety: a secondary meta-analytic review using robust variance estimation in meta-regression". Journal of Behavioral Medicine. https://pubmed.ncbi.nlm.nih.gov/31004323/
[5-3] Cole et al. 2022. “Stanford Neuromodulation Therapy (SNT): A Double-Blind Randomized Controlled Trial”. American Journal of Psychiatry. https://pubmed.ncbi.nlm.nih.gov/34711062/
[5-4] Bartoli et al. 2018. “Temporal Dynamics of Human Frontal and Cingulate Neural Activity During Conflict and Cognitive Control”. Cerebral Cortex. https://pubmed.ncbi.nlm.nih.gov/29028974/
Can we say that the left DLPFC is the governor of how we interpret physiological signals and spontaneous thoughts?
What is mapped in the anterior cingulate? What things in the body and the mind make the cingulate fire?
Fun fact: Andrew Huberman is super hypnotizable
[7-1] Swick and Jovanovic 2002. “Anterior cingulate cortex and the Stroop task: neuropsychological evidence for topographic specificity”. Neuropsychologia. https://pubmed.ncbi.nlm.nih.gov/11931927/
[7-2] Bokor and Anderson 2014. “Obsessive-compulsive disorder”. J. Pharm Pract. https://pubmed.ncbi.nlm.nih.gov/24576790/
[7-3] Diering and Bell 1991. “Functional neurosurgery for psychiatric disorders: a historical perspective”. Stereotact Funct Neurosurg. https://pubmed.ncbi.nlm.nih.gov/1842976/
[7-4] Banks et al. 2015. “Neuroanatomical characteristics associated with response to dorsal anterior cingulotomy for obsessive-compulsive disorder”. JAMA Psychiatry. https://pubmed.ncbi.nlm.nih.gov/25536384/
[7-5] Arnts et al. 2020. “On the pathophysiology and treatment of akinetic mutism”. Neurosci Biobehav Rev. https://pubmed.ncbi.nlm.nih.gov/32044373/
[7-6] Bolgov et al. 2022. "The structure of catatonia in depression and depressive-delusional conditions". Zh Nevrol Psikhiatr Im S S Korsakova. https://pubmed.ncbi.nlm.nih.gov/35797200/
[7-7] Walther and Strik 2016. “Catatonia”. CNS Spectr. https://pubmed.ncbi.nlm.nih.gov/27255726/
[7-8] Choi et al. 2017. “The Dissociative Subtype of Posttraumatic Stress Disorder (PTSD) Among Adolescents: Co-Occurring PTSD, Depersonalization/Derealization, and Other Dissociation Symptoms”. J Am Acad Child Adolesc Psychiatry. https://pubmed.ncbi.nlm.nih.gov/29173740/
Popular treatments for depression include ketamine which is a dissociative anesthetic.
Others include psilocybin and MDMA that lead to the exact opposite state of highly engaged emotionality, heart rate, and sense of self → leading to alleviation of depression.
How could a drug that induces dissociative states (ketamine) AND a drug that induces hyper-associative states (MDMA) could lead to relief of the same system?
[8-1] Corriger and Pickering 2019. “Ketamine and depression: a narrative review” Drug Des Devel Ther. https://pubmed.ncbi.nlm.nih.gov/31695324/
[8-2] Williams et al. 2018. "Attenuation of Antidepressant Effects of Ketamine by Opioid Receptor Antagonism. Am J Psychiatry 175:12. https://ajp.psychiatryonline.org/doi/pdf/10.1176/appi.ajp.2018.18020138
[8-3] Cameron et al. 2020. “A non-hallucinogenic psychadelic analogue with therapeutic potential”. Nature 589, 474-479. https://www.nature.com/articles/s41586-020-3008-z
Selective serotonin re-uptake inhibitors. These are powerfully effective in OCD and depression but potentially not in the way we're thinking they're working. There seems to be data that suggest there is no correlation between serotonin levels and depression.
What could be happening that explains the therapeutic benefit of SSRI's given their potential lack of correlation to serotonin?
[9-1] Williams et al. 2021. "Accelerated Neuromodulation Therapy for Obsessive-Compulsive Disorder. Brain Stimulation. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8114181/
Synesthesia could be like a Stroop test of sorts where your brain interprets colors, sounds, sights, using alternate areas of perception. In the psychedelic experience, this could be important for affecting the ability of the depressed individuals to change the “Rule” creation laws that govern their thought.
Why would the brain hold on to rules that don't serve use well? We hold onto these memories from an evolutionary perspective in that they allow us to perform in similarly negatively valanced situations. But in the modern world, this doesn't serve us as well.
What about psilocybin and related molecules (in terms of their neurochemistry) that allow this novel rule consideration phenomenon? Reconsolidation of a memory in the neuroplastic state of psychedelics could help the memory to rest in one's mind.
What do these trials show? Are they effective after 1 or 2 sessions? Psilocybin and MDMA
[11-1] Krystal et al. 2021. "Psychotherapy-supported MDMA treatment for PTSD”. Cell Rep Med. https://pubmed.ncbi.nlm.nih.gov/34467253/
[11-2] Mitchell et al. 2021. “MDMA-assisted therapy for severe PTSD: a randomized, double-blind, placebo-controlled phase 3 study”. Nature Med. https://pubmed.ncbi.nlm.nih.gov/33972795/
[11-3] Goodwin et al. 2022. “Single-Dose Psilocybin for a Treatment-Resistant Episode of Major Depression”. New England Journal of Medicine. https://pubmed.ncbi.nlm.nih.gov/36322843/
The study group that first identified that MDMA may be neurotoxic in a study on monkeys later published a follow-up that determined that the first set of studies actually utilized methamphetamine (which is known to be neurotoxic) to the monkeys and not MDMA. Therefore, it was not true that the initial study showed a neurotoxic effect of MDMA. The correction did not make as big of a splash in popular press.
Group of individuals that only took MDMA and group of individuals that did not take MDMA. There was no neurocognitive profile differences which proved that MDMA is not damaging. Although this didn't have a pre-post MDMA exposure, it showed a comparative study which is pretty good.
Purity of MDMA substances is guaranteed in clinical studies, but maybe not so much in other settings (raves). There is a reported drop in energy for a few days after using MDMA. Very likely this could have to do with a surge in prolactin subsequent to the big surge of dopamine in MDMA [12-2]. Huge lifts in dopamine also cause huge increases in prolactin which has an effect on libido, energy, and fatigue [12-3].
MDMA is an amphetamine and thus has effects on the dopaminergic system but psilocybin is very much a neutral or lightly dopamine, much more of a serotonergic drug [12-4].
[12-1] Ricuarte et al. 1988. “(+/-)3,4-Methylenedioxymethamphetamine selectively damages central serotonergic neurons in nonhuman primates”. JAMA. https://pubmed.ncbi.nlm.nih.gov/2454332/
[12-2] Hysek et al. 2013. “MDMA enhances emotional empathy and prosocial behavior”. Soc Cogn Affect Neurosci. https://pubmed.ncbi.nlm.nih.gov/24097374/
[12-3] Fitzgerald and Dinan 2008. “Prolactin and dopamine: what is the connection? A review article”. J Psychopharmacol. https://pubmed.ncbi.nlm.nih.gov/18477617/
[12-4] Carhart-Harris et al. 2016. “Psilocybin with psychological support for treatment-resistant depression: an open-label feasibility study”. Lancet Psychiatry. https://pubmed.ncbi.nlm.nih.gov/27210031/
Psilocybin being a serotonergic drug operates on the 5HT serotonin 2A receptors [13-1]. What is psilocybin doing in the brain over time?
[13-1] Castro Santos and Gama Marques 2021. “What is the clinical evidence on psilocybin for the treatment of psychiatric disorders? A systematic review”. Porto Biomed J. https://pubmed.ncbi.nlm.nih.gov/33884324/
[13-2] Preller et al. 2020. “Psilocybin Induces Time-Dependent Changes in Global Functional Connectivity”. Biol Psychiatry. https://pubmed.ncbi.nlm.nih.gov/32111343/
[13-3] Cole et al. 2021. “Stanford Neuromodulation Therapy (SNT): A Double-Blind Randomized Controlled Trial”. The American Journal of Psychiatry. https://ajp.psychiatryonline.org/doi/10.1176/appi.ajp.2021.20101429
Is the untethering from the autonomic system important? i.e. letting go of physical control and leaving the medical professionals in charge of keeping you safe.
[14-1] “Exposure and Response Prevention”. Psychology Today. https://www.psychologytoday.com/us/therapy-types/exposure-and-response-prevention
[14-2] Breeksema et al. 2022. “Holding on or letting go? Patient experiences of control, context, and care in oral esketamine treatment for treatment-resistant depression: A qualitative study”. Front Psychiatry. https://pubmed.ncbi.nlm.nih.gov/36506427/
Normal scores for depression is not zero, with some sadness being considered as absolutely normal. The Montgomery-Asberg Depression Rating Scale (MADRS) is clinically user in adults 18-years or older [15-1]. The cutoff points for the scale are, as curated by [15-2]:
Anecdotally from Dr. Williams, the MADRS scores of 0-10 is the normal range and same on the OCD scale, with mildly abnormal around the 10. Psychiatric diagnosis is when it severely impacts your ability to function. It really is a range of the disease spectrum where some degree of OCD, depression, etc. is within the normal range if it doesn't impair your life but when it starts to affect life and the ability to function then it gets diagnosed.
[15-1] “Montgomery-Asberg Depression Rating Scale (MADRS)”. MDCalc. https://www.mdcalc.com/calc/4058/montgomery-asberg-depression-rating-scale-madrs#why-use
[15-2] “Montgomery–Åsberg Depression Rating Scale”. Wikipedia. 17 October 2022. https://en.wikipedia.org/wiki/Montgomery%E2%80%93%C3%85sberg_Depression_Rating_Scale
[15-3] Muller-Thomsen et al. 2005. “Detecting depression in Alzheimer's disease: evaluation of four different scales”. Archives of Clinical Neuropsychology. https://academic.oup.com/acn/article/20/2/271/2760?login=false
[15-4] Herrman et al. 1998. “The Sunnybrook Stroke Study: A Prospective Study of Depressive Symptoms and Functional Outcome”. Stroke. https://www.ahajournals.org/doi/10.1161/01.STR.29.3.618
What is ibogaine?
What does this have to do with the Toad?
Note: The book by Daniel Pinchbeck mentioned by Dr. Huberman has been linked below in [16-1].
[16-1] Pinchbeck, Daniel. 2002. Breaking Open the Head: A Psychedelic Journey into the Heart of Contemporary Shamanism. Broadway Books. ISBN 0-7679-0742-6.
[16-2] Wasko et al. 2018. “DARK Classics in Chemical Neuroscience: Ibogaine”. ACS Chem Neurosci. https://pubmed.ncbi.nlm.nih.gov/30216039/
[16-3] Meisner et al. 2016. “Ibogaine-associated cardiac arrest and death: case report and review of the literature”. Ther Adv Psychopharmacol. https://pubmed.ncbi.nlm.nih.gov/27141291/
[16-4] Barsuglia et al. 2018. “A case report SPECT study and theoretical rationale for the sequential administration of ibogaine and 5-MeO-DMT in the treatment of alcohol use disorder”. Prog Brain Res. https://pubmed.ncbi.nlm.nih.gov/30471678/
[16-5] Davis et al. 2020. “Psychedelic Treatment for Trauma-Related Psychological and Cognitive Impairment Among US Special Operations Forces Veterans”. Chronic Stress. https://pubmed.ncbi.nlm.nih.gov/32704581/
What is it used for clinically?
Should ibogaine be recreational?
[17-1] “An Observational Pre-post Study Evaluating the Safety of Tabernanthe Iboga Exposure”. U.S. National Library of Medicine: ClinicalTrials.gov. https://clinicaltrials.gov/ct2/show/study/NCT04313712?term=Nolan+Williams&draw=2
Ayahuasca is a sacramental psychadelic in Brazil, Peru, Ecuador, and other South American countries. It is a two plant combination, whose individual parts do little without the combination. Out of 20,000 plants in the forest, these two specifically being combined results in a potent psychadelic. Cooking it for 5-10 hours removes the DMT from one of the plants and the reversible monoamine oxidase inhibitor from the other plant - such that the reversible monoamine oxidase inhibitor prevents the GI breakdown of DMT and thus allows it to make it to the brain. Therefore, without the reversible monoamine oxidase inhibitor, it would never cross the blood brain barrier and cause a hallucinogenic effect. If it wasn't a reversible inhibitor, then it would throw you into a serotonin syndrome [18-1]. Dr. Williams describes ayahuasca as very safe, and describes small children who have been exposed to small doses in tribal settings have no neurocognitive deficit as assessed by a psychiatrist from UCLA Harbor. There have also been some studies that have evaluated ayahuasca as an antidepressant agent [18-2, 18-3].
Brazilian Prisoner Study
The Brazilian Prisoner study, as described by Dr. Williams and Dr. Huberman, seems to have began around 2015 although I had trouble locating good sources for the study. From what they said, it appears that half of the prisoners were given inert substance and half were given ayahuasca. They describe that the study found statistically significantly lower recidivism rate for prisoners given ayahuasca than those given inert substance. Here are two potential references I found that may describe the study they're referring to: [18-4] [18-5].
[18-1] “Serotonin syndrome”. Mayo Clinic. January 22 2022. https://www.mayoclinic.org/diseases-conditions/serotonin-syndrome/symptoms-causes/syc-20354758
[18-2] Palhano-Fontes et al. 2019. “Rapid antidepressant effects of the psychedelic ayahuasca in treatment-resistant depression: a randomized placebo-controlled trial”. Psychol Med. https://pubmed.ncbi.nlm.nih.gov/29903051/
[18-3] Faria Sanches et al. 2016. “Antidepressant Effects of a Single Dose of Ayahuasca in Patients With Recurrent Depression: A SPECT Study”. J Clin Psychopharmacol. https://pubmed.ncbi.nlm.nih.gov/26650973/
[18-4] “In Brazil, Some Inmates Get Therapy with Hallucinogenic Tea”. New York Times. March 2015: https://www.nytimes.com/2015/03/29/world/americas/a-hallucinogenic-tea-time-for-some-brazilian-prisoners.html?smid=tw-share
[18-5] Aaron, Kase.“Brazil Offers Ayahuasca To Violent crime Inmates on Their Path to Redemption”. https://reset.me/story/brazil-offers-ayahuasca-to-violent-crime-inmates-on-their-path-to-redemption/
Dr. Williams and Dr. Huberman mentioned a Lancet psychology report on 18-20 yr old subjects' use of cannabis that demonstrated the exacerbation of psychosis in later life by cannabis use. There were counter points regarding the tendency of those users to seek pharmacologically-mediated help however the effect size was large as pointed out by Dr. Huberman. Although I was unable to determine exactly which report they were referring to, I've gathered two potential reports from Lancet including [19-1] Di Forti et al. 2015 which found that high potency cannabis in South London might have resulted in greater numbers of first onset psychosis in 18-65 year olds than previous studies; and [19-2] Crow 2015, which found that in a 15-year follow-up of 45,570 conscripts in the Swedish army there were 21 cases of schizophrenia among the 752 who had taken cannabis >50 times; this represented a 6x increased relative risk and the authors note that the schizophrenia was not found at age 21 but the individuals were 3x more at risk of other psychiatric diagnosis.
For more information on cannabis and psychosis, there was a thorough review article published in 2018 by Bettina Ortiz-Medina et al. that assessed 66 papers (23 cohort trials and 43 reviews) and concluded that Cannabis roughly doubles the risk of developing psychosis in vulnerable people [19-3]
The two primary chemicals involved in Cannabis are Tetrahydrocannabinol (THC) and Cannabidiol (CBD). There is a THC-free cannabis strain (Charlotte's Web). CBD at high doses is anti-psychotic and anti-schizophrenic. CBD has been bred out of cannabis over time for THC content, but THC is pro-psychotic and pro-schizophrenic. High doses of THC has driven some individuals to psychosis for short periods of time, and once the THC clears from their system the psychosis resolves. The balance of THC and CBD matters critically in the balance of psychotic and schizophrenic downstream effects. CBD was given to children who have severe, seizures and was shown to help with symptoms when other treatments (barbiturates, bromide) were ineffective. However, high THC load in adolescents before pre-frontal maturation (approx. < 25 years) may have some role of developing psychosis. Adolescents and children who have not experienced pre-frontal maturation should not be exposed to THC-containing substances including cannabis for the potential to develop psychosis in adult life.
[19-1] Di Forti et al. 2015. “Proportion of patients in south London with first-episode psychosis attributable to use of high potency cannabis: a case-control study”. Lancet Psychiatry. https://pubmed.ncbi.nlm.nih.gov/26359901/
[19-2] Crow 2015. “Cannabis and Psychosis”. Lancet Psychiatry. https://pubmed.ncbi.nlm.nih.gov/26360274/
[19-3] Bettina Ortiz-Medina et al. 2018. “Cannabis consumption and psychosis or schizophrenia development." Int J Soc Psychiatry. https://pubmed.ncbi.nlm.nih.gov/30442059/
Alcohol is ranked number one as the most dangerous drug in the world, ahead of cocaine, heroine, and other drugs in it's harm to others [20-1]. Dr. Williams thinks there is a chance that alcohol follows a similar path to smoking, where a threshold moment will allow prompt universities and hospitals to remove/prohibit alcohol consumption due to it's highly negative effects on human health as well as it's danger ranking.
[20-1] Nutt et al. 2010. “Drug harms in the UK: a multicriteria decision analysis”. The Lancet. https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(10)61462-6/fulltext
The foundation of mental health, physical health, and high performance is to try to get enough quality deep sleep for 80% of the nights of your life, just like exercise and good social behavior.
Triple Therapy:
Dr. Greg Sahlem, who is a professor at Stanford, has done a lot of work with sleep, particularly sleep deprivation. One night of sleep deprivation will have an anti-depressant effect but after the following night of sleep, they come into the same level of initial depression. Insomnia is highly related to depression, with symptoms of depression having a range of sleep disruptive effects. The triple therapy involves sleep depriving an individual, then shifting their phase of sleep, and simultaneously exposing them to bright light in an attempt to re-entrain their circadian rhythm [21-1]. From the Triple Therapy trials, there was a fairly durable and profound anti-depressant effect. This should not be done at home due to the complexities involved, as noted by Dr. Williams. Sleep deprivation is a profound anxiety agent and thus should be done under medical supervision.
[21-1] Sahlem et al. 2014. “Adjunctive triple chronotherapy (combined total sleep deprivation, sleep phase advance, and bright light therapy) rapidly improves mood and suicidality in suicidal depressed inpatients: An open label pilot study”. Journal of Psychiatric Research. https://www.sciencedirect.com/science/article/pii/S0022395614002519?via%3Dihub
TMS studies for treating depression have been done since around 1995 [22-1] and FDA clearance has been granted for TMS treatments around 2008 [22-2]. Before precision instruments, researchers were using rulers to approximate left DLPFC and ice to keep the coil at low temperatures but still able to engineer the stimulation.
The Stanford Neuromodulation Therapy (SNT) study uses TMS as a device to deliver a treatment [22-3]. The treatment is the protocol of stimulation parameter set in a specific brain region for each specific condition. This means that different conditions can be treated by using the same TMS device to deliver a different treatment, i.e. different parameters to a different brain region. Condition-specific and patient-specific treatment regimens are the future of TMS, and are actively discussed in literature such as Cash et al. 2020 which describe the identification of a target for use in all patients as well as a personalized target for each individual patient [22-4].
[22-1] George et al. 1995. “Daily repetitive transcranial magnetic stimulation (rTMS) improves mood in depression”. Neuroreport. https://pubmed.ncbi.nlm.nih.gov/8547583/
[22-2] Horvath et al. 2010. “The NeuroStar TMS device: conducting the FDA approved protocol for treatment of depression”. J vis Exp. https://pubmed.ncbi.nlm.nih.gov/21189465/
[22-3] Cole et al. 2022. “Stanford Neuromodulation Therapy (SNT): A Double-Blind Randomized Controlled Trial”. American Journal of Psychiatry. https://pubmed.ncbi.nlm.nih.gov/34711062/
[22-4] Cash et al. 2020. “Using Brain Imaging to Improve Spatial Targeting of Transcranial Magnetic Stimulation for Depression”. Biol Psychiatry. https://pubmed.ncbi.nlm.nih.gov/32800379/
The stimulation protocol can be modified but run through the same TMS device. In 2005 a group published a paper in Neuron to demonstrate that if you stimulate with the Hippocampal rhythms through a TMS coil, you can excite the brain with memory rhythms and it lasts an hour. Although I'm not certain this is the exact publication mentioned by Dr. Williams, Huang et al. 2005 published on a related topic in Neuron [23-1] and Paulus 2005 [23-2] also published a commentary on the results of Huang et al. 2005, pointing at it's impact. Other groups next looked to implement 6-week schedules for repeated TMS programs. Interestingly, groups are working on optimizing and reorganizing the time-course of the treatment approach by using Space Learning Theory.
Space Learning Theory is a psychological nuance best explained by the following example:
Space Learning Theory has been applied to TMS by altering the time-course of stimulation to align with our psychological nuances. To put it more clearly, by theta-burst stimulating a hippocampal slice (from a mouse in the example study), you will induce some enlarged dendritic spines and some primed dendritic spines. Interestingly, if you re-stimulate immediately after you will see very little if any change, but if you wait 1-1.5 hours you get even more enlarged and even more primed dendritic spines. Dr. Williams used this Space Learning Theory to reorganize 6-weeks of TMS to properly fit into 1-day and 9-months of TMS in 5-days, where each day is roughly 10-hours of temporally spaced 9-minute sessions and it abides by the 1-1.5 rest time. 60-90% of the time, patients will go into total remission quantified as a normal mood by the end of session. Some remission ranges as verbalized by Dr. Williams range from 1-year to 4-years.
Fun Fact: Ketamine also causes the same enlargement and increased priming of dendritic spines as theta stimulation by Space Learning Theory spacing in time.
[23-1] Huang et al. 2005. “Theta burst stimulation of the human motor cortex”. Neuron. https://pubmed.ncbi.nlm.nih.gov/15664172/
[23-2] Paulus 2005. “Toward establishing a therapeutic window for rTMS by theta burst stimulation”. Neuron. https://pubmed.ncbi.nlm.nih.gov/15664167/