Lightning-Nl
Bluelighter
- Joined
- Nov 11, 2012
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J Neurophysiol. 1994 Aug;72(2):1024-7.
Importance of unpredictability for reward responses in primate dopamine neurons.
Mirenowicz J, Schultz W.
J Neurophysiol. 1998 Jul;80(1):1-27.
Predictive reward signal of dopamine neurons.
Schultz W.
There's even a cool slide to back it up with.
Scientists recorded the activity of dopamine neurons in the VTA of a rat (or presumably some other unfortunate little critter) and graphed them around the stimulus-reward interval, both before they learned the stimulus gave them a reward, during the process of learning, and then afterwards.
from the Neuron review on this
So what does this mean?
Let's say you live on rice and beans for a long, but indefinite period of time. You work 9 to 5 at Burger Parthenon and don't go out much. Now your friend Steve, from out of town, comes in and invites you to party with him. Steve is loaded, a trust fund kid. Maybe you don't trust him at first because of the social standing, or you don't like his cologne or whatever. But regardless, out of boredom, you go out with him, hit the bars, scope out girls (or guys, if that's what you're into). The novelty and feeling of freedom are liberating and make you feel awesome. That night you pass out exhausted, and return to your doldrum day job again. Steve calls you a few weeks later, the same things happen, you go out on the town and feel great, maybe even better than last time.
(A dopamine response is induced via pleasurable behaviour - wine women, and song - in response to a stimulus - Steve calling you)
Since Steve works on an oil rig far away, though, his visits are spotty at best. Steve calls you a few months later, the next time it happens, and then a week after that. Work at Burger Perthnon is hard. You eventually start to anticipate when he'll call - as soon as you see Steve's name flash on your phone you know you'll be having a good time again. You start to relax and feel better knowing there's plans for the weekend - even though they haven't been made yet because you haven't answered his call!
(The dopamine neuron response migrates from the reward = party - to the stimulus - Steve)
Eventually Steve moves next door to you. Seems like a good idea - you can hit the town on a regular basis. So you do. But once it's a planned thing and the Friday call comes in ... bar-hopping with Steve stops being so exciting. The magic is lost.
(The dopamine neurons adjust their response to a continuous reward in response to the stimulus).
The same thing happens in lots of scenarios, with any reward and stimulus.
It seems to me this system is in place for 2 reasons:
1. Discourage repetitive activity that results in no improvement to encourage energy be spent elsewhere - scratching of itches, sexual activity, defecation etc are normally pleasurable, but you don't see people fixate on them, usually.
2. Encourage novel risk-taking behaviours. If you go exploring and find a specimen of your favourite fruit tree in a hidden grove, bearing a delicious juicy fruit just for you, you'd feel more satisfied than going to a fruit orchard and picking a fruit from there. Both experiences are more rewarding than going to the supermarket - as long as you don't live on a farm, that is.
The theory that chills during urination are tied to heat loss makes more sense to me than urination being intrinsically rewarding. It is indeed critical to our survival - without waste removal one would surely perish - but in general, defecating more doesn't increase your prospects at advancing the species.
For most people I have to assume it is not going to be a random result whether their bladder is going to empty or not - and even then, I know of nobody toilet-trained who gets really happy when they have to piss, because of the upcoming reward!
Just wanted to say; this is, without a doubt, one of THE best posts on Bluelight.
I was unaware that I had bought into the misconception that Dopamine is a reward hormone hook, line, and sinker.
With all the other combined knowledge I have, I was able to apply the information you provided to a possible (and very probable) explanation to the mechanism behind Obsessive-Compulsive Disorder, Pathological Addictions (Such as Compulsive Gambling and Shopping), Impulse Control Disorders and the impulsiveness due to ADHD (although, I believe that more is going on than just Dopamine reinforcing the reward aspect of emotion, in the case of ADHD)
I was also able to identify why I, personally, have compulsive buying issues, why I can't resist taking a drug if it's in front of me (even though I am not addicted to anything persay. I never crave a substance or actively seek them out. If they are in front of me, however, I can't stop myself from using the substance.), and why I actively try to seek-out CC information, and other things, when I know that doing so will cause long-term negative consequences.
So, I figured that Dopamine was playing a big role in that behavior, and I decided to try an experiment. When I felt a really intense impulse to do something, I took the antipsychotic Risperidone. Usually, when I have an impulse as intense as the one I as felt in that situation - it builds up to the point that I can't suppress the urge to act on it anymore and it gets put into action. When Risperidone was taken, the impulse was gone in around 30 minutes. The only down side to Risperidone (or any other Dopamine antagonist for that matter) I am literally so unmotivated that I can't do anything.
I was also able to identify why my ADHD meds (Vyvanse 70MG's atm) was causing me to be more impulsive - when it should have the opposite effect. I noticed that when Vyvanse was taken at the same time as Lamotrigine - It eliminated all the impulsiveness I felt due to the Vyvanse.
I based this on the fact that I believed that Lamotrigine was a Serotonin agonist. After doing immense research on the Mesolimbic Reward Pathways, I noticed that studies mentioned that the feeling of "reward" has an immense relationship with Serotonin release. So, at the time, I thought taking Lamotrigine would be a good fit with the Vyvanse as I thought Lamotrigine would cause increased neuronal firing due to 5-HT3 agonism.
I have since learned that Lamotrigine is a possible Serotonin antagonist. However, there are many conflicting things on the internet about Lamotrigine mechanism of action. All websites I looked at said that Lamotrigine binds to 5-HT3 and Sigma-1, however, each website had different info for whether or not Lamotrigine is an Agonist, Antagonist, or Inverse Agonist. I know wikipedia says it's an antagonist at 5-HT3 and Sigma-1, however, no sources are cited so I don't count that as credible (even though it might be correct)
So I'm not sure, at this point in time why Lamotrigine would cause a synergistic effect with Vyvanse. Oddly enough, taking the Lamotrigine with the Vyvanse would greatly boost the stimulating effects of Vyvanse, while at the same time, oddly decreasing my impulses to do something negative.
Can anyone input their thoughts on the matter?
Anyways, this post became about something entirely different than I originally posted it about. Just wanted to say to sekio that; your information literally led me to solving literally everything that's wrong with my behavior.
You, sir, deserve an award.