Menu
Recruiting NCT06344559

Brain Criticality, Oculomotor Control, and Cognitive Effort

No phase Interventional Healthy

For patients and families

In plain language

An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.

What is being studied
The protocol lists: transcranial magnetic stimulation.
Who it may be relevant to
Registry conditions: Healthy. Basic parameters: 18 years — 45 years · All.
What needs checking
Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
Where it takes place
United States
Next step
Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →

Unsure about the terms? Read our patient guide →

Official title

Theta-burst Stimulation Modulates Criticality and Cognitive Control

Overview

The project examines electroencephalography, MRI, and behavioral measures indexing flexibility (critical state dynamics) in the brain when healthy young adults do demanding cognitive tasks, and in response to transcranial magnetic stimulation.

Detailed description

The healthy human brain is a complex, dynamical system which is hypothesized to operate, at rest, near a phase transition - at the boundary between order and chaos. Proximity to this critical point is functionally adaptive as it affords maximal flexibility, dynamic range, and information transmission capacity, with implications for short term memory and cognitive control. Divergence from this critical point has become correlated with diverse forms of psychopathology and neuropathy suggesting that distance from a critical point is both a potential biomarker of disorder and also a target for intervention in disordered brains. The Investigators have further hypothesized that task performance depends on how closely brains operate to criticality during task performance and also that subjective cognitive effort is a reflection of divergence from criticality, induced by engagement with demanding tasks.

A key control parameter determining distance from criticality in a resting brain is hypothesized to be the balance of cortical excitation to inhibition (the "E/I balance"). Transcranial magnetic stimulation is a widely used experimental and clinical tool for neuromodulation and theta-burst stimulation (TBS) protocols are thought to modulate the E/I balance. Here the Investigators test whether cortical dynamics can be systematically modulated away from the critical point with continuous theta-burst stimulation (cTBS) and intermittent theta-burst stimulation (iTBS), which is thought to decrease and increase E/I balance, respectively. Depending on baseline E/I balance prior to stimulation, this will make people's brains either operate closer to, or farther away from critiality and thereby impact on cognitive control and subjective cognitive effort during performance of control-demanding tasks.

Interventions

  • Device transcranial magnetic stimulation
    The study intervention involves modulation of cortical excitation to inhibition (E/I) balance in the right frontal eye field (FEF) by means of 2 trains of spaced continuous or intermittent theta burst stimulation (cTBS, iTBS, respectively) using a transcranial magnetic stimulation device. The endpoint of this stimulation will be a decrease (cTBS) or increase (iTBS) in the local E/I ratio that should last at least 60 minutes post-stimulation (Chung et al., 2016). In separate sessions, all partic

Primary outcome measures

  • Critical dynamics - immediate effects of cTBS versus sham stimulation [Time frame: Change in correlations recorded during rest, immediately after stimulation, for active versus sham stimulation.]
  • Functional E/I balance - immediate effects of cTBS versus sham stimulation [Time frame: Change in the functional E/I balance recorded during rest, immediately after stimulation, for active versus sham stimulation.]
  • Avalanche branching ratio - immediate effects of cTBS versus sham stimulation [Time frame: Change in the avalanche branching ratio recorded during rest, immediately after stimulation, for active versus sham stimulation.]
  • Critical dynamics - immediate effects of iTBS versus sham stimulation [Time frame: Change in correlations recorded during rest, immediately after stimulation, for active versus sham stimulation.]
  • Functional E/I balance - immediate effects of iTBS versus sham stimulation [Time frame: Change in the functional E/I balance recorded during rest, immediately after stimulation, for active versus sham stimulation.]
  • Avalanche branching ratio - immediate effects of iTBS versus sham stimulation [Time frame: Change in the avalanche branching ratio recorded during rest, immediately after stimulation, for active versus sham stimulation.]
  • Memory-guided saccade accuracy - effects of cTBS versus sham stimulation [Time frame: Change in degrees of visual angle error estimated 44 minutes after stimulation, for cTBS versus sham stimulation.]
  • Memory-guided saccade accuracy - effects of iTBS versus sham stimulation [Time frame: Change in degrees of visual angle error estimated 44 minutes after stimulation, for iTBS versus sham stimulation.]
  • Anti-saccade accuracy - effects of cTBS versus sham stimulation [Time frame: Change in percent accuracy estimated 12 minutes after stimulation, for cTBS versus sham stimulation.]
  • Anti-saccade accuracy - effects of iTBS versus sham stimulation [Time frame: Change in percent accuracy estimated 12 minutes after stimulation, for iTBS versus sham stimulation.]

Eligibility criteria

Inclusion criteria

  • Provision of signed and dated informed consent form
  • Stated willingness to comply with all study and availability for the duration of the study
  • Males and females; Ages 18-45
  • Healthy, neurologically normal with no diagnosed mental or physical illness
  • Willingness to adhere to the MRI and two session stimulation protocol
  • Fluent in English
  • Normal or corrected to normal vision
  • At least twelve years of education (high school equivalent)

Exclusion criteria

  • Ongoing drug or alcohol abuse
  • Diagnosed psychiatric or mental illness
  • Currently taking psychoactive medication
  • Prior brain injury
  • Metal in body
  • History of seizures or diagnosis of epilepsy
  • Claustrophobia
  • Pregnant or possibly pregnant
  • Younger than 18 or older than 45
  • Use of medications which potentially lower the usage threshold

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Allocation
Randomized
Model
Crossover
Masking
Double blind
Primary purpose
Basic science

Study locations

United States · 1 center
  • Center for Advanced Human Brain Imaging Research — Piscataway

Publications

  • Huang YZ, Edwards MJ, Rounis E, Bhatia KP, Rothwell JC. Theta burst stimulation of the human motor cortex. Neuron. 2005 Jan 20;45(2):201-6. doi: 10.1016/j.neuron.2004.12.033. PMID 15664172
  • Chung SW, Hill AT, Rogasch NC, Hoy KE, Fitzgerald PB. Use of theta-burst stimulation in changing excitability of motor cortex: A systematic review and meta-analysis. Neurosci Biobehav Rev. 2016 Apr;63:43-64. doi: 10.1016/j.neubiorev.2016.01.008. Epub 2016 Feb 3. PMID 26850210

Identifiers

NCT: NCT06344559 · 2023001006

Primary sources (government registries)

View this study on ClinicalTrials.gov ↗