Transcranial Direct Current Stimulation Effect on Pain Threshold and Working Memory in Healthy Adolescents, Young Adults and Elderly: a Randomized , Cross-over, Single Blind Trial
Overview
- Phase
- Not Applicable
- Intervention
- Not specified
- Conditions
- Transcranial Direct Current Stimulation
- Sponsor
- Hospital de Clinicas de Porto Alegre
- Enrollment
- 30
- Locations
- 1
- Primary Endpoint
- Heat pain Threshold
- Status
- Completed
- Last Updated
- 6 years ago
Overview
Brief Summary
Transcranial direct current stimulation (tDCS) is a non-invasive neuromodulation method which has great potential as an aid in the therapeutic management of neuropsychiatric disorders and chronic pain syndromes. However, despite promising results, the response to stimulation presents great variability among subjects. Age is a factor that is known to influence the tDCS effect forging the inconsistency of clinical effect.The purpose of this study is to evaluate the effect of tDCS on pain perception and working memory in healthy women from 3 different age groups: adolescents, young adults and elderly. This is a randomized, single-blinded, cross-over study of 2 different active interventions and sham.
Detailed Description
Transcranial direct current stimulation (tDCS) is a neuromodulation method that has great potential as an aid in the therapeutic management of neuropsychiatric disorders and chronic pain syndromes. tDCS modulates the neuronal membrane potential , facilitating neuronal depolarization or hyperpolarization, hence modifying the cortical excitability of the stimulated area. However, despite promising results the response to stimulation presents great variability among subjects. Chronological age is an important factor in the variation of brain plasticity. The dorsolateral prefrontal cortex (DLPFC) is associated with cognitive and emotional aspects of pain, in addition to being related to executive components of working memory. Anodal tDCS on DLPFC modulates pain level in patients with chronic pain and modifies working memory performance in healthy subjects and patients with memory impairment. The prefrontal cortex presents a great structural difference throughout lifespan: it is under maturational process in the adolescence, reaching peak of maturation in the adult life, and initiating process of cerebral senescence in elderly subjects. Therefore, the use of tDCS on DLPFC in these three age groups presents potential for a large variation in response. Faced with the potential of tDCS for adjuvant use in the treatment of several diseases, it is imperative to understand the variability of this intervention between different age groups. This knowledge may allow the optimization of neuromodulation protocols, allowing more careful and refined use in the clinic. The study primary outcomes is the difference between and within age groups on the variation of pre and post tDCS on pain threshold evaluated by Heath pain threshold on a Quantitative sensory testing paradigm and working memory performance evaluated by n-back test in healthy subjects of three age groups: adolescents, young adults, elderly. This is a randomized, single blinded, cross-over, sham-controlled clinical trial. The study will be conducted at the Clinical Research Center of the Hospital de Clínicas of Porto Alegre (HCPA). It will include 30 women, 10 women by age group: adolescents between 15 and 16 years,young adults between 30 and 40 years old and elderly women between 60 and 70 years. Participants will be randomized for a cross-over of three sessions: anodal stimulation in DLPFC, anodal stimulation in primary motor cortex (M1) as active control and sham stimulation.
Investigators
Eligibility Criteria
Inclusion Criteria
- •Age between 15 to 16 years for the adolescent group
- •Age between 30 to 40 years for the young adult group
- •Age between 60 to 70 years for the elderly group
- •From completed elementary school to incomplete superior education
- •right handed
Exclusion Criteria
- •Pregnancy
- •Current smoker or previous smoker within 10 years
- •Current Substance Use Disorder
- •Neurological condition (e.g., traumatic brain injury, stroke, brain tumor, epilepsy, brain surgery, brain implant)
- •Any diagnosed Psychiatric condition (e.g., Attention deficit/hyperactivity deficit (ADHD), bipolar disorder, major depressive disorder, schizophrenia, generalized anxiety disorder)
- •Use of any antidepressive or psychoactive, psychostimulant medication
- •Any chronic pain condition
Outcomes
Primary Outcomes
Heat pain Threshold
Time Frame: percentual change from before the tDCS onset, to immediately after the end of tDCS application for each cross-over session
Using the Quantitative sensory testing, this measure consists of the average temperature of 3 stimulus with increasing magnitude of heat where the participant presses a button to indicate when he/she first perceives pain.
Working memory performance
Time Frame: up to 60 minutes after tDCS onset
Working memory performance will be evaluated by a computerized n-back test associated with flankers at baseline and after each session of active tDCS (DLPFC or M1) or sham. The measure of performance is the D' discrimination index (calculated based on hit rate and false alarm rate).
Secondary Outcomes
- serum BDNF levels(up to 60 minutes before tDCS onset)
- Inhibitory control performance(up to 60 minutes after tDCS onset)
- Heat pain tolerance(percentual change from before the tDCS onset, to immediately after the end of tDCS application for each cross-over session)
- Moderate pain(percentual change from before the tDCS onset, to immediately after the end of tDCS application for each cross-over session)
- Theta wave power(up to 60 minutes after tDCS onset)
- Area under the curve of the ERP during inhibitory control task(up to 60 minutes after tDCS onset)
- Alpha wave power(up to 60 minutes after tDCS onset)
- Beta wave power(up to 60 minutes after tDCS onset)
- Heat thermal threshold(percentual change from before the tDCS onset, to immediately after the end of tDCS application for each cross-over session)
- Unpleasantness sensation(percentual change from before the tDCS onset, to immediately after the end of tDCS application for each cross-over session)