When the ventral striatum generates a goal-directed behavior, i.e. I want to do this to get that (e.g. turning on a light switch in a dark room) dopamine
(the brain’s happy dance drug) releases in the mesolimbic pathway (the brain’s Reward Freeway).8-12
When a G/D behavior comes from the ventral striatum, it makes the dorsal striatum more likely to repeat the action than if it comes from the PFC. 12-17
This is why you cannot think your way out of an addiction. The PFC, or thinking part of the brain
, just does not have the dopamine
firepower the ventral striatum has. The ventral striatum is in the old non-thinking survival-first part of the brain, where the mantra is “do it now, ask questions later”.18-22
So, what this part of the brain lacks in cognition
, it makes up for in dopamine.
In addition, both the ventral and dorsal striatum release dopamine, although they utilize it differently, serving different purposes in the brain. In the dorsal striatum, dopamine initiates action, but in the ventral striatum, it signals reward.12,16,23-26 Thus, dopamine release in the ventral striatum makes you want to do something because you anticipate the reward of doing it. Evolution invested more dopamine in making us want to do something than in actually doing it because getting us to want to do something is essential to our doing it. Once we are doing it, the game is over. 27-31So, people do not realize that addiction is deconstructing their lives because a) wanting to do it is what feels good, not doing it, and b) repetition turns a goal directed behavior of, “I want A so I do B” into a S/R behavior of when I see A I do B. It is like walking into a room, knowing the bulb is out, yet you flip the light switch out of habit. Walking into a dark room is the stimulus, flipping the switch is the response. Once thought is taken out of the process the response becomes a habit.
So in terms of Robin William’s struggle with addiction, I get it. No, I did not know him well, and hadn’t seen him in years, but I know addiction very well and see it every day. This I know. It takes no prisoners, and it does not know uptown from down, famous from obscure, rich from indigent, no races, no nations, and no political affiliations. It does not matter how successful you are, who loved you and how much. Addiction is highly individualized and your brain does the best it can: end of story. 32-35
Addiction and Depression
Addiction and depression are like booger sugar and hairless nostrils. Where you find one, you find the other.36-41 Until recently scientist thought that there was a neurochemical basis for major depressive disorders. However, we are learning that major depressive disorders are associated with reduced regional volumes in the Central Nervous System (CNS).42-46 Studies have also found that fewer and smaller glia cells, as well as neurons, in discrete brain areas are associable to major depressive disorders.44
This is new science, and we have not fully articulated the precise structural and functional changes in the brain and the Central Nervous System that cause major depressive disorders. However, think about it like this. Glia cells are involved in myelination. Myelination is like the rubber casing around wires. You know what happens when the wire casing gets compromised and an electrical wire is exposed. Likewise, you also know what happens when the wires are too small to carry the current.
By Dr. Billi Gordon/ Property of UCLA CNS
I know depression intimately. It is like Seattle, or Dublin in October… rainy, and dreary. It wefts in and out, like the fog over the rooftops of Dublin, and hangs heavily on your spirit like a firmament that dampens your soul. More importantly, depression is not a weather condition for some people. For some people it is a climate. The recent findings regarding compromised brain and CNS volumes, along with reduced cell numbers, and smaller sized cells and diminished functionality support the climate theory, more so than a weather condition that can be avoided or zapped with pharmaceuticals like farmers seeding clouds.
What should we take from Robin Williams’ death? This: struggles with addiction and depression are not about who you are, what your character is like, or what your life is like, but merely about what your brain can and cannot endure, and for how long. Robin Williams’ life gave us tremendous joy; its punctuation gave us tremendous sorrow. But life is driven by a differential engine, and without sorrow, joy would have no value. Thus, maybe in that small way his death complimented his life, in that it was extraordinary, albeit, extraordinarily sad. He had his struggles with addiction like many of us, and depression swept over him, as it does many of us. The lesson there: like you know there is a sun, even though it is raining; like you believe in love even if you cannot feel it; on days like this, you must trust the Universe, even though you cannot understand what it is, or why it is, the Universe is doing, what She is doing. Remain fabulous and phenomenal.
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