The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers
Trial registered on ANZCTR


Registration number
ACTRN12615000886583
Ethics application status
Approved
Date submitted
12/08/2015
Date registered
25/08/2015
Date last updated
28/11/2019
Date data sharing statement initially provided
28/11/2019
Date results information initially provided
28/11/2019
Type of registration
Prospectively registered

Titles & IDs
Public title
Brain stimulation, aging and cognition: Investigating neuroplasticity and cognitive enhancement following brain stimulation in amnestic mild cognitive impairment.
Scientific title
Effect of transcranial direct current stimulation on neuroplasticity and cognitive performance in adults with amnestic mild cognitive impairment
Secondary ID [1] 287266 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Amnestic Mild Cognitive Impairment 295888 0
Condition category
Condition code
Neurological 296139 296139 0 0
Neurodegenerative diseases
Neurological 296201 296201 0 0
Alzheimer's disease
Mental Health 296274 296274 0 0
Studies of normal psychology, cognitive function and behaviour

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Transcranial direct current stimulation (tDCS) involves the application of a weak electric current to the scalp to non-invasively increase cortical excitability. Two surface electrodes are attached to the scalp. The anode is placed on the left dorsolateral prefrontal cortex and the cathode on the right forehead. Participants sit upright in a chair and are awake and alert for the period of stimulation.

Participants will be asked to attend for two sessions, spaced at least one week apart, with each session lasting approximately 2 hours. In each session tDCS will be applied by a trained researcher for two 13 minute blocks with a 20 minute break between. The first block of tDCS will be either active (2mA) or sham stimulation, with the second block active. Sessions will be counterbalanced across participants.
Intervention code [1] 292567 0
Treatment: Devices
Intervention code [2] 292621 0
Treatment: Other
Comparator / control treatment
Performance will be compared across the sham and active conditions. Sham stimulation will involve an identical set up and duration to active stimulation however no current will be applied.
Control group
Placebo

Outcomes
Primary outcome [1] 295815 0
N-back task (accuracy and reaction time)
Timepoint [1] 295815 0
30 minutes post final block of stimulation.
Primary outcome [2] 295816 0
TMS-EEG evoked potential amplitudes which provide an indication of prefrontal cortex activity in response to tDCS.
Timepoint [2] 295816 0
5 and 20 minutes post the final block of stimulation
Secondary outcome [1] 316594 0
EEG oscillations across the scalp in areas relevant to network activity.
Timepoint [1] 316594 0
5 and 20 minutes post the final block of stimulation.

Eligibility
Key inclusion criteria
a) Subjective and objective memory complaints. Objective memory complaints are defined as >1.5SDs below the mean on visual or verbal memory tasks, OR
b) Healthy adults aged between 18 - 35 years OR 56 - 80 years with no cognitive complaints.
Minimum age
18 Years
Maximum age
80 Years
Gender
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
* History of seizures or neurological disorders
* Current psychiatric diagnoses, alcohol or substance dependence
* Left-handed
* Presence of metal in head
* Women who are currently pregnant or lactating
* Individuals taking benzodiazepines or acetyl cholinesterase inhibitors

Study design
Purpose of the study
Treatment
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Who is / are masked / blinded?



Intervention assignment
Other design features
Phase
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
VIC

Funding & Sponsors
Funding source category [1] 291825 0
University
Name [1] 291825 0
Monash University
Address [1] 291825 0
Wellington Rd
Clayton
VIC 3800
Country [1] 291825 0
Australia
Primary sponsor type
University
Name
Monash University
Address
Wellington Rd
Clayton
VIC 3800
Country
Australia
Secondary sponsor category [1] 290488 0
None
Name [1] 290488 0
Address [1] 290488 0
Country [1] 290488 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 293344 0
Alfred Hospital Ethics Committee
Ethics committee address [1] 293344 0
Alfred Hospital
55 Commercial Rd, Melbourne VIC 3004
Ethics committee country [1] 293344 0
Australia
Date submitted for ethics approval [1] 293344 0
Approval date [1] 293344 0
16/07/2014
Ethics approval number [1] 293344 0

Summary
Brief summary
Amnestic mild cognitive impairment (a-MCI) is believed to represent a transition period between normal aging and Alzheimer's disease. People with a-MCI experience problems with their memory without it impacting on their daily functioning. As a-MCI represents a stage prior to irreversible neurodegeneration, it is important from a therapeutic perspective that neural changes occurring in a-MCI are determined in order to see if there remains potential for response to treatment.

Neuroplasticity refers to the brains ability to re-organize its function in response to the environment. One aspect of this is known as long-term potentiation (LTP), which is imperative in learning and memory. LTP-like plasticity can be induced through brain stimulation techniques including transcranial direct current stimulation (tDCS). Application of tDCS through a gentle electrical current can increase brain activity as measured through electroencephalography (EEG) and behavioural outcomes. When transcranial magnetic stimulation (TMS) is applied in combination with EEG, the cortical excitability of the stimulated and surrounding brain regions can be determined. This provides information about the LTP-like plasticity that is present. Recent evidence has shown that spaced application of tDCS may be more beneficial in enhancing cognitive performance and neural plasticity compared to only a single session.

Therefore the aim of our study is to investigate whether LTP can be induced in a-MCI and if there are differences in LTP-like plasticity and cognitive performance with spaced application of tDCS compared to a single active tDCS condition.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 51782 0
Ms Melanie Emonson
Address 51782 0
Monash Alfred Psychiatry Research Centre
Level 4
607 St Kilda Rd
Melbourne
VIC 3004
Country 51782 0
Australia
Phone 51782 0
+613 9076 9823
Fax 51782 0
Email 51782 0
melanie.emonson@monash.edu
Contact person for public queries
Name 51783 0
Ms Melanie Emonson
Address 51783 0
Monash Alfred Psychiatry Research Centre
Level 4
607 St Kilda Rd
Melbourne
VIC 3004
Country 51783 0
Australia
Phone 51783 0
+61 3 9076 9823
Fax 51783 0
Email 51783 0
melanie.emonson@monash.edu
Contact person for scientific queries
Name 51784 0
Ms Melanie Emonson
Address 51784 0
Monash Alfred Psychiatry Research Centre
Level 4
607 St Kilda Rd
Melbourne
VIC 3004
Country 51784 0
Australia
Phone 51784 0
+61 3 9076 9823
Fax 51784 0
Email 51784 0
melanie.emonson@monash.edu

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
Not approved in ethical protocol
What supporting documents are/will be available?
No other documents available
Summary results
Have study results been published in a peer-reviewed journal?
No
Other publications
Have study results been made publicly available in another format?
No
Results – basic reporting
Results – plain English summary