Related Experiment Video
Updated: May 14, 2026
10:58
TMS: Using the Theta-Burst Protocol to Explore Mechanism of Plasticity in Individuals with Fragile X Syndrome and Autism
Published on: December 28, 2010
16.9K
Fluoxetine does not influence response to continuous theta burst stimulation in human motor cortex
Duncan K Austin1,2, Lourenço M D Amador1,3, Lucia M Li1,4
1University College London, London, UK.
Neuropsychopharmacology Reports
|November 7, 2024
Summary
A single dose of fluoxetine did not alter brain responses to continuous theta burst stimulation in healthy volunteers. This suggests prior findings on selective serotonin reuptake inhibitors and brain stimulation may need larger sample sizes.
Area of Science:
- Neuroscience
- Psychopharmacology
- Neurophysiology
Background:
- Selective serotonin reuptake inhibitors (SSRIs) are hypothesized to modulate synaptic plasticity, a key mechanism in brain function.
- Non-invasive brain stimulation techniques like continuous theta burst stimulation (cTBS) can probe synaptic plasticity in vivo.
- Previous research suggested SSRIs might influence the cortical excitability changes induced by cTBS.
Purpose of the Study:
- To investigate the effect of a single dose of fluoxetine, an SSRI, on cortical excitability.
- To determine if fluoxetine modulates the motor evoked potential (MEP) response to cTBS.
- To clarify the interaction between SSRIs and non-invasive brain stimulation.
Main Methods:
- Thirty-one healthy participants underwent two sessions: one with 20mg fluoxetine and one with placebo, in a randomized order.
- Spaced continuous theta burst stimulation was applied to the motor cortex in each session.
- Changes in motor evoked potentials (MEPs) were recorded for 60 minutes post-stimulation.
Main Results:
- There was no significant difference in the MEP response to cTBS between fluoxetine and placebo conditions.
- A notable proportion of participants exhibited an unexpected paradoxical excitatory response to cTBS.
- The study did not find evidence that fluoxetine alters the inhibitory effects of cTBS.
Conclusions:
- A single 20mg dose of fluoxetine does not impact the neurophysiological response to cTBS.
- The findings challenge previous suggestions of SSRI modulation of inhibitory brain stimulation protocols.
- Insufficient sample sizes in prior studies may explain discrepancies in reported SSRI effects on brain stimulation.
More Related Videos
11:11Effects of Transcranial Alternating Current Stimulation on the Primary Motor Cortex by Online Combined Approach with Transcranial Magnetic Stimulation
Published on: September 23, 2017
9.0K
06:42Continuous Theta Burst Stimulation of the Posterior Medial Frontal Cortex to Experimentally Reduce Ideological Threat Responses
Published on: September 28, 2018
11.6K
Related Concept Videos
01:21Paracrine Signaling
Paracrine signaling allows cells to communicate with their immediate neighbors via secretion of signaling molecules. Such a signal can only trigger a response in nearby target cells because the signal molecules degrade quickly or are inactivated if not taken up. Prominent examples of paracrine signaling include nitric oxide signaling in blood vessels, synaptic signaling of neurons, the blood clotting system, tissue repair/wound healing, and local allergic skin reactions. Nitric oxide as a...
01:24Muscle Recovery and Fatigue
Muscle fatigue refers to the decline in a muscle's ability to maintain the force of contraction after prolonged activity. It primarily stems from changes within muscle fibers. Even before experiencing muscle fatigue, one may feel tired and have the urge to stop the activity. This response, known as central fatigue, occurs due to changes in the central nervous system, namely the brain and spinal cord. While there is no single mechanism that induces fatigue, it may serve as a protective response...
01:27Exercise and Muscle Performance
Exercise induces a range of adaptations in muscle tissue, depending on the type and duration of activity. Such physical training can be broadly categorized into two types: endurance exercises and resistance exercises.
Endurance exercises
Endurance exercises involve running, swimming, or cycling, which require repetitive movements with low force output. When a person engages in endurance exercise, a few noticeable changes occur in their skeletal muscles. For instance, the number of capillaries...
Endurance exercises
Endurance exercises involve running, swimming, or cycling, which require repetitive movements with low force output. When a person engages in endurance exercise, a few noticeable changes occur in their skeletal muscles. For instance, the number of capillaries...
01:16Sympathetic Activation
The sympathetic division can influence tissues and organs by releasing norepinephrine at peripheral synapses and distributing epinephrine and norepinephrine through the bloodstream. In times of crisis or stress, sympathetic activation occurs, which is regulated by sympathetic centers in the hypothalamus. As a result, sympathetic activation prepares the body for physical exertion, rapid ATP production, and heightened alertness, allowing individuals to respond effectively to challenging or...
01:20Exercise and Cardiovascular Response
Exercise significantly impacts cardiovascular response, which is crucial for understanding patient health and designing effective treatment plans.
Light to moderate physical activity initiates a series of interconnected responses in the body. The heart rate modestly increases in anticipation of the workout, followed by widespread vasodilation as oxygen consumption by skeletal muscles increases. This results in decreased peripheral resistance, increased capillary blood flow, and accelerated...
Light to moderate physical activity initiates a series of interconnected responses in the body. The heart rate modestly increases in anticipation of the workout, followed by widespread vasodilation as oxygen consumption by skeletal muscles increases. This results in decreased peripheral resistance, increased capillary blood flow, and accelerated...
01:26Exercise Stress Test
Introduction
Exercise stress testing, commonly known as a treadmill test, is a noninvasive procedure used to evaluate cardiovascular function and diagnose heart conditions.
Definition
An exercise stress test measures the heart's response to exertion using a treadmill or stationary bicycle. Chest electrodes record the heart's electrical activity through an ECG, and blood pressure is monitored regularly.
Purposes
Exercise stress testing, commonly known as a treadmill test, is a noninvasive procedure used to evaluate cardiovascular function and diagnose heart conditions.
Definition
An exercise stress test measures the heart's response to exertion using a treadmill or stationary bicycle. Chest electrodes record the heart's electrical activity through an ECG, and blood pressure is monitored regularly.
Purposes