Remember, the brain has two halves, mirroring each other. Therefore we have two of everything.
The basal ganglia have a limbic sector whose components are assigned distinct names: the nucleus accumbens, ventral pallidum, and ventral tegmental area (VTA).
A complex part of the brain is located just above the brainstem. It is like the motherboard and CPU of a computer. In fact, it is connected to the brainstem as well as most of the major parts of the brain with neurons, neurochemicals and hormones. It affects motor control, emotions and memory with input from all sensory systems.
Because I am trying not to get too complicated, I will over simplify and skip a lot of detail. However, I will include the following from Wikipedia to give a flavor of the power and impact of this portion of the brain
Function: The shell of the nucleus accumbens (roughly in Brodmann area 34) is involved in the cognitive processing of reward perception, subjective “liking” reactions to certain pleasurable stimuli, incentive salience for rewarding stimuli (specifically, the NAcc shell determines the value of and assigns the “desire” or “wanting” attribute of a stimulus), and positive reinforcement. A “hedonic hotspot” or pleasure center which is responsible for the pleasurable or “liking” component of some intrinsic rewards is also located in a small compartment within the medial NAcc shell. The subset of ventral tegmental area projection neurons that synapse onto the D1-type medium spiny neurons in the shell appear to be responsible for immediate drug reward (i.e., “wanting”). Addictive drugs have a larger effect on dopamine release in the shell than in the core. D2-type medium spiny neurons in the shell appear to be associated with aversion-related cognition.
That is hard to understand. The Life Model states it this way:
The nucleus accumbens is the brain’s pleasure and pain center. This nucleus contributes strongly to addictions, [sexual drive] and most importantly, our attachment to those we love. If we do not receive a response in return we feel pained, rejected, unloved, abandoned, jilted, dumped, and alone or unwanted.
Alright. Before I lose you completely let me explain what this is all about. Deep in the center of our brains is the control mechanism for receiving input from our eyes, ears, smeller, taster, and feelers. This assigns a level of like or dislike to every memory and decides what to do with the information: i.e. action or where to store it in memory. When there is no stress, things work well. When there is stress, things sometimes malfunction. Let’s not say malfunction because it does continue to function according to design. What happens however, is we become overloaded. Remember the loading dock where too many trucks come in at once and things get backed up?
Let’s continue with the description of the brain:
The circuitry of the basal ganglia is both complicated and detailed — As well as somewhat disputed.
Multiple models of basal ganglia circuits and function have been proposed. However there is currently a debate about the pathway divisions, pathway overlap and pathway regulation.
The effects are far reaching and all encompassing. Role in motivation: Extracellular dopamine in the basal ganglia has been linked to motivational states in rodents, with high levels being linked to satiated “euphoria”, medium levels with seeking, and low with aversion. The limbic basal ganglia circuits are influenced heavily by extracellular dopamine. The disinhibition of the thalamus leads to activation of the prefrontal cortex and ventral striatum, selective for increased D1 activity leading to reward.
I can’t believe I understood this when I researched it. Basically, it says that the information not only goes into action, it is also involved in Decision Making and Working Memory. Later, we will learn there are levels of memory. But I don’t want to get too complicated. All we need to know is that we hurt, and how can we heal.
Hippocampus