Written by: Dr. Luis Fernandez
Depression is a real and tangible condition to an outside observer (I.E. the psychiatrist). The sufferer, however, might experience it as a sense of failure, lack of will, or something to blame on the self. Peers might suggest “snapping out of it” or may reflect back “how perfect and beautiful” one’s life may be. These comments do not aid the sufferer. If the depressed individual could “snap out of it” they would have done so promptly. To those who suffer from depression, I offer known facts related to the physical and electrical state of the brain. Much like any other part of the body, the brain is an organ. It can get sick just like the heart in congestive heart failure or the kidneys in chronic kidney disease. There are measurable changes in the functioning of the organ.
Structural differences have been known to exist in the brains of those who suffer from depression. Post-mortem studies have shown a decrease in both frontal lobe interneurons and glial cells. After years of chronic depression, a widening of the lateral ventricles may occur. One can now couple this knowledge with the findings of functional imaging (showing in real-time what areas of the brain may be active). What the sufferer feels is not merely imagined as some may suggest. It is reflected in the structure and function of the brain.
Functional imaging techniques like fMRI show a correlation between depression and the persistent activation of “the default mode network.” When the brain is idle, certain areas act in unison to create this “network.” Its activation has correlated with increased rumination and self-reflection; features experienced in depression.
Treatment involves much more than neurotransmitter balances and instead may depend on neural plasticity. Electroconvulsive therapy (ECT), a brain stimulation therapy offered at UTHealth, offers remission rates of 60-80%. In comparison, medication may confer ~30% remission (where remission is the elimination of the majority of symptoms).
How does the brain undergo plastic changes? Electroconvulsive Therapy induces seizures artificially by the use of a physiologically compatible electrical stimulus. Unlike the waves drawn from a wall socket, ECT instead delivers discrete block-like pulses that minimize side effects. This induces a seizure with the least possible amount of energy. It’s the brain’s ability to extinguish the seizure (going from full synchronized activity to full silence) that is thought to play into the antidepressant effects. As the brain undergoes additional seizures, it learns to extinguish it faster and faster. The changes involved in this (plastic adaptability) are thought to alleviate depression. Much like the use of antidepressant medication, ECT results in an increase in Brain Derived Neurotrophic Factor (BDNF). This “nourishes” the neurons and is associated with neuronal regeneration in areas involving memory. It also alters the metabolism of certain areas involved in the condition.
Each ECT session takes less than 40 minutes and takes place under the care of a psychiatrist and an anesthesiologist. The pt is put briefly under anesthesia (~5 minutes) and given a muscle relaxant. The seizure is induced with a 1-8 second train of pulses and lasts less than one minute. Once the pt is out of anesthesia he/she will then be observed by nursing until fully recovered. Common side effects include a muscle-related headache (the stimulus also directly contracts these muscles briefly), slight muscle aches (side effect from succinylcholine – the neuromuscular relaxer).
It is my experience that patients usually appear brighter to others as early as the 4th treatment. The patients will usually report feeling better after the 6th. They may require anywhere between 6 and 12 treatments with the possibility of maintenance doses at fixed intervals (monthly, etc).
The treatment is, in my opinion, under-used given its robust efficacy. In the past, cognitive effects did limit its use as many patients experienced retrograde and anterograde amnesia. The evolution of the technique, however, is one that now minimizes this while also continuing to offer predictable, positive responses.
Electroconvulsive Therapy is one of many brain stimulation techniques offered at UTHealth. There will be more to come regarding this topic.