None listed
Conditions
Brief summary
Many people with Huntington’s disease (HD) experience problems with motivation, often referred to as “apathy”. This is thought to be because of how HD affects the frontal lobes of the brain. There are currently no effective treatments for apathy in HD. Recent research has looked at whether non-invasive brain stimulation can improve motivation in people experiencing other neurological conditions (e.g., stroke) with some promising results. The type of brain changes caused by HD mean that a gentle, non-invasive type of brain stimulation called transcranial alternating current stimulation (tACS) may be most effective. But there are different ways that tACS can be used, and some ways may be more effective than others. The purpose of this project is to investigate the best way of using tACS so that it changes brain activity and improves performance on a motivation task in people with HD as well as people without HD. If we can find an effective way of using tACS, then this may help in the development of interventions for reduced motivation in HD. This research project requires participants to attend three separate testing sessions during which they receive 20 minutes of tACS, have their brain activity recorded via EEG, and complete a task exploring motivation. During each session participants receive tACS targeting a different frequency. By frequency, we mean electrical brain waves. In one session they receive tACS at a low frequency (i.e., in the “delta” frequency range). In another session they receive tACS set at a middle frequency (i.e., in the “alpha” frequency range). In a third session they will receive sham (i.e., placebo) tACS.
Interventions
Randomized and counterbalanced sequence of three sessions of transcranial alternating current stimulation (tACS) conducted at least 72 hours apart, with details as follows:
1) 20 minutes and 2mA at the participants peak individualised alpha frequency;
2) 20 minutes and 2mA at 2Hz (delta frequency);
3) 20 minutes of sham (placebo) with 30 seconds 'fade in' followed by an immediate 30 seconds 'fade out'.
TACS is administered using a Startstim wireless hybrid electroencephalography(EEG)/transcrania
Randomized and counterbalanced sequence of three sessions of transcranial alternating current stimulation (tACS) conducted at least 72 hours apart, with details as follows: 1) 20 minutes and 2mA at the participants peak individualised alpha frequency; 2) 20 minutes and 2mA at 2Hz (delta frequency); 3) 20 minutes of sham (placebo) with 30 seconds 'fade in' followed by an immediate 30 seconds 'fade out'. TACS is administered using a Startstim wireless hybrid electroencephalography(EEG)/transcranial current stimulation 8-channel system (Neuroelectrics, Spain). EEG obtained via a 50-channel Neuroscan EEG system. All data collection (baseline measures, resting and task-related EEG) and tACS administration is conducted by Marie-Claire Davis (Registered Psychologist with practice endorsement in Clinical Neuropsychology and PhD candidate).
Sponsors
Monash University
Study design
Allocation
Randomised controlled trial
Primary purpose
Treatment
Eligibility
Sex/Gender
All
Age
18 Years to 75 Years
Healthy volunteers
Yes
Inclusion criteria
- Individuals with genetically confirmed prodromal or early stage HD, as well as individuals without HD matched for age, gender and education will be sought as participants. - Participants with prodromal HD will need to be within approximately 12 years of expected motor onset or have a “disease burden score” (DBS) of at least 280, indices calculated using the prospective participant’s current age and number of CAG repeats on the affected allele. - Participants with early stage manifest HD will need to have a total functional capacity (TFC) score greater than, or equal to 10 . The TFC is used to assess how much assistance a person with HD requires to perform tasks in five functional domains that decline with disease progression (i.e., occupation, finances, domestic chores, activities of daily living, and care level).
Exclusion criteria
- Use of anticonvulsant medications or regular treatment with benzodiazepines (versus limited as-needed use, with none consumed within the 48 hours prior to an experimental session). - Commencement or significant dosage alteration of other psychotropic medications (i.e., anti-depressants, anti-psychotics) during the four weeks prior to an experimental session. - Choreiform movements that preclude tACS or EEG data collection. - A current episode of psychiatric illness, or a current substance use or alcohol use disorder, initially assessed via the recruitment screen, and then as assessed and defined by the Mini International Neuropsychiatric Interview (MINI) 7.0.2. - Any history of significant head injury or traumatic brain injury, as defined by a loss of consciousness greater than 30 minutes or requiring a hospital admission. - Unstable medical illness. - Pregnancy or breastfeeding. - An uncorrected hearing or visual impairment (including difficulty with colour perception). - Significant difficulties with understanding or communicating in English. - Metallic implants within the head, a pacemaker, cochlear implant, medication pump or other electronic device within the body.
Outcome results
None listed