(Dopaminergic Dysfunction in Late-Life Depression)

Did you know that many older adults with depression usually also have poor motivation, difficulty making decisions, and feel slowed down, making it hard to get around? These are important symptoms we see with depression that do not always respond well to current antidepressant medications.


But, these symptoms may be caused by a common problem: dopamine! Dopamine is a chemical messenger released by nerve cells that plays an important role in motivation, decision making, and motor function, such as how fast we move and how well we can get around. Brain dopamine decreases as we age, but not much is known about the role dopamine plays in older adults with depression.

There are currently approved medications that affect dopamine, but they are not well studied in depression. A few antidepressant medicines affect dopamine, but not the majority of them.

The purpose of this study is:

  1. To see whether dopamine function is related to depressive behaviors

  2. To determine whether depressive symptoms improve with medications that increase dopamine

This study will help determine if medications that affect dopamine should be further studied for depression. It will also help determine who may be more likely to benefit from dopamine medications.

We are seeking adults age 60 or older who either:

Are currently depressed and also feel like they are thinking or moving slowly


Have never been depressed, and are willing to serve as a comparison subject


For those individuals who are depressed, this study is includes an investigational medication that affects dopamine. We want to determine if the medicine can improve depressive symptoms and slowness in thinking or walking performance.

For those without a history of depression, you will not be asked to take the investigational medication. Since you have no lifetime history of depression, we will gather information from you to compare with people who are currently depressed.


You may be eligible to participate if you are depressed and:

  • Are 60 years of age or older
  • Do not have a history of alcohol dependence or substance abuse in the last 12 months
  • Are able to have an MRI scan
  • Are able to have a PET scan
  • Are currently experiencing symptoms of depression
  • Feel like you are thinking or moving slowly
  • Have no other mental health problems, other than depression and anxiety

If you have no lifetime history of depression, you may be eligible to participate if you:

  • Are 60 years of age or older
  • Do not have a history of alcohol dependence or substance abuse in the last 12 months
  • Are able to have an MRI scan
  • Are able to have a PET scan
  • Have no lifetime history of mental health problems
  • Do not have a first degree relative (parent, sibling, or child) with a history of depression


What is involved in the study?


Interested? Great! First you will have a preliminary telephone call or survey to make sure you are eligible. If you appear eligible and agree to participate, you will complete an initial screening visit to see if you qualify for the study.

The screening visit takes about 2.5-3 hours and will take place at Vanderbilt University Medical Center. This visit will include an interview and a physical assessment. For currently depressed participants, this will also include a walking test and a response speed test.

A telemedicine/video screening visit may be available. Please use the contact information below if you are interested in learning more about this option.

After you complete the screening process, you will then enter a baseline period. The baseline period will last up to 4 weeks and will include 2-4 in-person visits. The total time required to complete the baseline period is about 11.5 hours spread over the multiple visits. During the baseline period, you will complete one blood draw, one Magnetic Resonance Imaging (MRI) brain scan, one Positron Emission Technology (PET) brain scan, questionnaires, memory tests, and walking tests.

If you have no lifetime history of depression, your participation will end after the baseline period.

If you are currently depressed, you will then enter the treatment portion of the study. This part of the study lasts 8-10 weeks. During this period, you will take the study medication and have at least weekly contacts to assess for any problems. After starting the study medication, you will also complete an additional MRI brain scan and repeat the memory and walking tests.

Why should I consider participation?

 Participants all have unique reasons for joining research studies.

By participating in this study, you are significantly helping us understand the causes of depression. This study may also inform how we treat depression in the future. You also get to learn more about your depression.

Although we cannot guarantee that you personally will benefit from participating, we try to make sure that all participants have a better understanding of their depression and a plan to help them recover.

We are dedicated and passionate about our research and could not do it without your help!

Will I be reimbursed or compensated?

Yes! Participants will receive monetary compensation for their time and efforts.


Frequently Asked Questions
  • Why nicotine?  

    Nicotine stimulates systems in the brain that are important for thinking and memory. The nicotine patch is currently approved by the U.S. Food and Drug Administration for smoking cessation, but it may also benefit other conditions, like memory loss. Past work also suggests that nicotine may help treat depression.

    Depressed Mind 2 researchers are specifically studying the potential benefits of nicotine to test whether it can improve or alleviate the symptoms of memory impairment in older adults with depression.

    What is nicotine?   Nicotine is most commonly known as an ingredient in cigarettes, but it may also have medicinal benefits. When not associated with smoking, researchers believe nicotine can stimulate brain systems associated with memory and attention and can be used to treat memory impairment in late-life depression.

    Is this study supported by the tobacco companies?   No. This study is supported by the National Institutes of Health (NIH).

    Where can I find out more about the results of your past study with nicotine?   Please click here to read more about our previous study.

    Doesn't nicotine cause cancer?   Nicotine does not cause cancer. Fifty years of public health messaging has been instrumental in helping people understand that smoking is detrimental to your health and may cause cancer, however nicotine is not to blame. It's the tar and thousands of other chemicals found in cigarettes that make smokers susceptible to cancer, heart disease, and respiratory issues. A small amount of nicotine absorbed through a patch on the skin is not the same as inhaling tar and other chemicals through the lungs while smoking.

    Isn't nicotine addictive?  

    Researchers have used nicotine in memory studies for more than 30 years. 

    There appears to be no or a very small risk of dependency or addiction when using the nicotine patch to treat mild memory loss or mild cognitive impairment (MCI). In earlier studies, researchers used the nicotine patch to treat MCI in non-smokers, and there were no signs of withdrawal symptoms or cravings after stopping use of the patch. In this same study, participants using nicotine patches showed more improvement in attention and memory loss than those using the placebo patches containing no nicotine.

    Does the nicotine patch have side effects?   All medications can cause side effects, but most people have no, or minimal, side effects when using the nicotine patch in memory studies. If they occur at all, the most common side effects are nausea, dizziness, and headaches. An important part of the screening process is to review your medical history and current medications to determine whether this study is right for you.

    What if I recently stopped smoking or live with someone who is a smoker?   Because of the investigational medication being used for this study, you must not have used tobacco or nicotine in the last year. You must also not live with someone who is a smoker, or have regular exposure to second hand smoke.

    If you are currently a smoker, have been a nonsmoker for less than a year, live with someone who is a smoker, or have regular exposure to secondhand smoker we may have other studies you could be eligible for. Please see the other studies listed on our website or click here to go to our contact information. We are happy to discuss our studies that are currently recruiting with you.


  • How long will my participation in the study last?   The screening visit and baseline visit will be completed within about 4 weeks of each other. If you baseline visit is spread out over two days, the visits must occur within 7 days of each other.

    Following the baseline visit, your participation in the study will last about 15 weeks.

    Will I receive results from my study?   We will notify you if there are any clinically important findings.

    If I am experiencing symptoms of depression, do I have to already be diagnosed with depression to participate?   You need to be taking an antidepressant medication to participate in this study. An assessment will be done at the screening visit to determine if you are eligible for the study.

    If I have a history of depression, what if I'm not currently experiencing symptoms of depression?   For this study, we are only enrolling people who are currently experiencing depression. If you have a history of depression but are currently doing well and not depressed, this may not be a good study for you. However we may have other studies you could be eligible for. Please see the other studies listed on our website or click here to go to our contact information. We are happy to discuss our studies that are currently recruiting with you.

    What if I have other mental health problems?   Individuals with a history of Bipolar Disorder, Post-Traumatic Stress Disorder (PTSD), Obsessive Compulsive Disorder (OCD), and Schizophrenia are not eligible at this time. People with anxiety are potentially eligible.

    Will I have to stop taking my current antidepressant medication(s)?   No. You will continue taking your currently prescribed antidepressant medication(s) for this study.

    If you do not want to continue taking your current antidepressant medication(s) for the duration of this study, we may have other studies you could be eligible for. Please see the other studies listed on our website or click here to go to our contact information. We are happy to discuss our studies that are currently recruiting with you.

    What if I don't want to take an investigational medication?   All currently depressed participants will take an investigational medication for this study. We may have other studies you could be eligible for that don’t involve investigational medications. Please see the other studies listed on our website, or click here to go to our contact information. We are happy to discuss our studies that are currently recruiting with you.

    Are there medical conditions that would exclude me from participating?   Yes. Participants cannot have a history of:


    • Major neurological disorders, such as dementia, stroke, brain tumors, seizures, Parkinson's Disease, or Multiple Sclerosis (MS).
    • Surgical implants that send electrical signals, such as pacemakers, cardio defibrillators, and spinal cord stimulators.

    There are also certain medications that are not allowed for this study. A study coordinator and/or study doctor will discuss with you all of the medications you are currently taking to see if you are eligible for this study.


    What if I don't live close to Vanderbilt University Medical Center?  

    Volunteers must be able to attend study visits at VUMC. Unfortunately, travel reimbursement is not available.

    How can I volunteer?   If you are 60 or older, click here to go to our contact information.
  • What does an MRI involve?   An MRI scan is performed in a large machine that is shaped like a tunnel. This scan does not use x-rays. Instead, they use a strong magnet and radio waves, like those used in an AM/FM radio, to make pictures of your body. We do not give you any drugs or injections for our scan.


    Are there any known risks of an MRI scan?  

    There are no known major risks with an MRI scan, although it is possible that you may be bothered by being placed in a tight space (claustrophobia) or by the noises made by the magnet during the scan.

    Before you can complete an MRI for the study, we will take a detailed medical and surgical history to assess you for MRI safety.

    Do I have to be able to have an MRI?  

    MRIs are required for this study. Currently depressed participants will complete 2 MRIs over the course of the study, while those without a history of depression will complete 1 MRI.

    Can I be sedated during the MRI scans? No, sedation is not permitted during the MRIs. We need participants to be awake so they can complete tasks in the scanner.

    I have metal implants. Are these safe for the MRI? Many medical implants and MRI-safe. During the screening visit, we will evaluate you for any surgical implants that may exclude you from having an MRI.
  • We are following all appropriate public health guidelines during the COVID19 Pandemic. We are going to be pre-screening people by phone. Once we have your information, it will be provided to the study doctor to review. We will then reach out to you via email or phone and discuss with you further screening activities.

    For more information about our safety guidelines, please click here.

    To visit the VUMC Coronavirus website, please click here.

  • The Laboratory of Affective and Cognitive Imaging is located within the Center for Cognitive Medicine at the

    Vanderbilt Psychiatric Hospital

    1601 23rd Ave South

    Nashville, TN 37212


  • If you have any additional questions or would like to find out if you may be eligible, please click here to be taken to our contact information.