3.5 Dopamine and the Brain's Reward System
Dopamine (DA), a primary neurotransmitter in the brain, can be thought of as a chemical messenger that relays information across highly interconnected neural pathways linking our emotions, with our sense of reward, and desire . When we encounter reward-predicting cues, such as seeing a person walking by with a huge ice-cream in hand, there’s an instantaneous and rapid increase in dopamine firing in our brain. It’s that increase in activity (and interest) that suddenly (and subconsciously) motivates us to find the nearest ice-cream store so we don’t miss our opportunity to experience pleasure. Recent research indicates that 70% of individuals suffering with attention deficit disorders (impulsivity) also suffer with metabolic disorders as well . The exact mechanics and chemistry underlying this bidirectional relationship in the brain are unknown. However current research implicates dysregulation of the dopamine system in both the brain and the pancreas which is critical to regulating insulin release and blood glucose control .
The reward circuitry in the brain spans two key brain regions, (1) the prefrontal region and the amygdala, and (2) the limbic system integrating the amygdala with the hypothalamus [30, 31]. Essentially these are the interfaces between US and Betty; Betty and Brian. When dopamine activity levels are low, we’re more likely to seek, consume, and even binge to avoid feeling depressed or in a state of withdrawal.
We discuss compulsive behaviors in chapter four, but compulsive-seeking behavior takes place when normal dopamine functioning is altered by repeated and excessive intake of substances . Most addictive substances are transformed from naturally occurring substances (e.g., tobacco; fermentation of material into alcoholic beverages, and grains, sugar and fat) into substances with unnaturally high concentrations of reinforcing ingredients (e.g., nicotine, ethanol, fats and sugar) . Withdrawal from UPND foods, simply triggers our cravings for more UPND foods. Even after periods of healthy or restrictive eating, if we return to eating UPND foods this will reinstate and re-trigger our UPND food-seeking behaviors. This is particularly true if we’re under the influence of stressors or negative emotional states.
How does UPND withdrawal affect you?
What cravings does it trigger?
What is the danger when you relapse on UPND foods?
Can you identify some of the emotions that follow a relapse episode?