Scientists have discovered clues to brain changes in depression

on 07 December 2018
Our brain under attack

Is it true, that the more enabled we become, the more disabled we feel? Depression as a condition is on the rise, more people are being diagnosed with it, month by month, year by year. That, despite the fact that medical interventions have never been so good. So, if the medical profession is getting better, why are we becoming worse. . . . 

The brain, a collection of mini-brains acting like one!

I sometimes get confused when scientists come up with seemingly novel ideas, based on research, about specific areas of the brain. In this particular piece of research, they focus on a part of the basal ganglia, the nucleus accumbens (NAcc), which is a part of the ventral striatum, the other part being the olfactory tubercle (OT). The striatum has two parts with two main areas in each, ventral striatum (mentioned above) and dorsal striatum. The dorsal striatum is made up of the caudate nucleus and the putamen.

While anything being found that will enhance the lives of people with depression is a great thing, I would have expected there to be more, relating to these findings, i.e. with regards to the striatum as a whole and any interplay between that and the other areas connected to the nucleus accumbens (NAcc), e.g. thalamus and the wider limbic system as a whole. Dopaminergic pathways, largely related to rewards, come from and through many brain areas, e.g. there are 4 main dopaminergic pathways: mesolimbic, mesocortical, nigrostriatal and tuberoinfundibular. Areas that these pathways connect with, apart from the striatum, are, ventral tegmental area (VTA), Substantia nigra, globus pallidus, hippocampus, thalamus, hypothalamus, amygdala, BNSY, periaqueductal grey, orbitofrontal and frontal cortex, to name but a few. The essence of my understanding is, that the many regions and areas of the brain perform many isolated and shared functions and that is the magic of the brain. However, one area stands out as being special, and that is, the ventral tegmental area (VTA). The VTA communicates with almost every area of the brain and almost every area that it connects to, connects back with it! 

The VTA plays a role in a number of our brain's processes, for example, cognitionmotivationorgasm, and, perhaps most importantly, the emotion we relate to as love. Although it would be better to think of this emotion, love, separately from our romantic perception of it. Important as that is, its major function is to create and sustain us as a species. Perhaps the maternal perspective of that love enables us to endure the time and effort it takes between being born and becoming functional human beings? Love, however, is best viewed as a neuro-chemical position that comes about in response to the awareness of wellbeing. That state of wellbeing, fortunately, is directly linked to our breathing, hence why we say to someone having an emotional meltdown - "calm down, take a deep breath!" So, if breathing has the ability to calm people it would seem amiss to ignore treatments that use this natural part of the body's defences.

Hypnosis or hypnotherapy is one such modality and despite it being recognised by both the British and American Medical Councils around 70 years ago, it is still not widely adopted as an effective treatment regime; why? Hypnosis or the effects of it, occur while we are in deeper states of mind (theta brainwaves) and collaterally bring about profound states of relaxation as well as influencing the way certain brain regions express themselves. And since the parts of the brain that bring about that transformation, mostly, report to the ventral tegmental area, I believe that is what is potentially involved in creating similar effects in clients I see, as has been demonstrated in this research! This, I believe, is because the VTA is somewhat instrumental in creating the responses demonstrated in this research, which is deemed as being consequential of the ventral striatum, NAcc?

Hypnotherapy stands out as one of the most effective strategic life management methods there is, especially in its ability to promote clear thinking and good states of mental wellness. The behaviours that make life challenging are often a result of too much stress, too little sleep and too little by way of clarity! So, to take back control of your mind and your life, it makes perfect sense to use a methodology that addresses the subconscious mind's role in perpetuating negative, vague and ambiguous states of mind. Hypnosis helps us to create calm relaxing states of mind that make life work better! If you would like to address any concerns you have in this direction, or, if you just want to make your life feel better,  then why not make an appointment for a Free Consultation? Hypnosis gives you the ability to have a good life! 

The objective here is to help people understand how and why we become illogically trapped into irrational emotional experiences that may actually be happening for reasons different to that which we would imagine! If you want to know more about how Hypnotherapy can help you; why not make an appointment for a Free Consultation?

For more information on the Free Consultation - Go Here Or, to book your Free Consultation today, you can do so here

The Research: 

In new pre-clinical research, scientists at the University of Maryland School of Medicine (UMSOM), led by Scott Thompson, PhD, Professor of Physiology, have identified changes in brain activity linked to the pleasure and reward system.

The research, published in the journal, Nature, provides new insights into how the brain processes reward pathways and advance our understanding of addiction and depression. The research, which was conducted by Tara LeGates, PhD, a Research Associate in the Department of Physiology, discovered that the strength of signals between two brain regions, the hippocampus and the nucleus accumbens, is critical for processing information related to a rewarding stimulus, such as its location.

"These two parts of the brain are known to be important in processing rewarding experiences," said Dr Thompson." The communication between these regions is stronger in addiction, although the mechanisms underlying this were unknown. We also suspected that opposite changes in the strength of this communication would occur in depression. A weakening of their connections could explain the defect in reward processing that causes the symptom of anhedonia in depressed patients." Anhedonia is the inability to enjoy normally pleasurable experiences, such as food, being with friends or family, and sex.

This research uncovered a key circuit in the brain of mice that is important for goal-directed behaviours and shows that the strength of the signals in this circuit are changeable, a process referred to as plasticity. Reward circuits and the molecular components that underlie their plasticity represent new targets for the development of treatments for disorders like addiction and depression.

Using Light-Sensitive Proteins

To activate or inhibit this connection, researchers used special light-sensitive proteins introduced into specific neurons in the brains of the mice. In mice with the light-sensitive protein that stimulated the neurons, just four seconds of light exposure not only activated this hippocampus-to-nucleus accumbens pathway while the light was on but persistently reinforced the strength of the signals along this pathway, creating an artificial reward memory.

A day later, the mice returned to the place where the artificial memory was created, even though they never experienced an actual reward there. Researchers then used light to silence the same pathway in mice with the light-sensitive protein that inhibited the neurons and found that this pathway is required for associating a reward with its location. The mice no longer showed a preference for the place where they had interacted with another mouse.

The researchers also examined this circuit in depressed mice. This pathway could not be enhanced using the stimulating light-sensitive protein. After receiving anti-depressant medication, the researchers could enhance this pathway using the light-sensitive protein and create artificial reward memories in the mice.

This work was funded by the National Institutes of Health, the Whitehall Foundation, and the Brain & Behavior Research Foundation (NARSAD Young Investigator Grant).

"These exciting results bring us closer to understanding what goes wrong in the brains of clinically depressed patients," said UMSOM Dean E. Albert Reece, MD, PhD, MBA, who is also the Executive Vice President for Medical Affairs, University of Maryland, and the John Z. and Akiko K. Bowers Distinguished Professor.

Story Source:

Materials provided by the University of Maryland School of MedicineNote: Content may be edited for style and length.

Journal Reference:

  1. Tara A. LeGates, Mark D. Kvarta, Jessica R. Tooley, T. Chase Francis, Mary Kay Lobo, Meaghan C. Creed, Scott M. Thompson. Reward behaviour is regulated by the strength of hippocampus–nucleus accumbens synapsesNature, 2018; DOI: 10.1038/s41586-018-0740-8

Cite This Page:

University of Maryland School of Medicine. "Clues to brain changes in depression: Using light-sensitive proteins, researchers study the brain's reward memory response." ScienceDaily. ScienceDaily, 30 November 2018. <>.