Neurodiversity Part 5:
Research on Anticipatory Reaction
As mentioned in Part 2, human behavior research into introversion and extroversion does not align with the public view of these terms. It isn't culled down to how shy or outgoing a person is. And the research dating back to brain scans in the 1960's and 70's shows similarities to the public definition of neurodiversity (coined in the 1990's by Judy Singer.)
Part 3 looked at blood flow in the brain.
Part 4 went over cortical arousal.
Now we'll be discussing anticipatory reactions, and behavioral systems will be covered in the next part.
Also, here is a link to the seven executive functions listed in a Psychology Today article for reference.
Now let's talk about dopamine differences. A study by Cohen et al was done to measure both introverts and extroverts' response to anticipatory rewards. Researchers wanted to see if anticipation alone could lead to a dopamine boost. The authors found that, unlike extroverts who could get a dopamine boost from anticipation by using consistent environmental cues from previous rewards, introverts were less likely to get that boost (if at all.) (Source)
If you look at the role of task-based reward, there may be a primal basis for this. When you have a task like hunting or gathering, it doesn't make sense if your mind would have you run into completing a task without more context. If an individual gets a significant boost of dopamine by just thinking about collecting food, they may not be paying attention to environmental cues that may signal danger. They need more context before they're driven to act. Lack of a dopamine boost will likely inhibit approach behavior, potentially keeping a person from walking into a literal lion's den. But a little dopamine boost might make them excited or intrigued on how to proceed. We've also talked about acetylcholine used for attention and focus on task-based stimuli. If dopamine is utilized over acetylcholine, could a person be missing essential information?
This study may also help explain why anticipation for introverts can lead to either a boost of excitement or dread. More context is needed to make sure that the choice you're making is correct, before you are motivated to move forward. But we’ll get into that more in the next section on the behavioral inhibition and activation systems. (Where a person may be more sensitive to those negative events to ensure that we are not following through with an event that could potentially hurt them or others.)
Ultimately, this anticipatory difference may affect the following executive functions: self-awareness, inhibition, nonverbal working memory, motivational regulation, and planning and problem-solving.
This may also help us understand how rewards and consequences may affect or be interpreted by someone.
- For those sensitive to anticipation, abstract outcomes such as social validation and shame may be provide enough of a boost to drive them to act. (Dopamine in and of itself is not a reward hormone -- it just helps us get excited for a potential reward.)
- Those that need more context likely prefer more concrete outcomes. Long-term rewards may not help motivate them day-to-day. And not being able to see what the reward is or imagine experiencing a reward may make it difficult to feel excited for something. Milestone rewards and natural consequences can work well for them instead. For example, knowing that they can grab take out after completing some of their bigger assignments, play video games once they get work done, or even knowing that they will have to miss out on a fun event if they don't finish ahead of time can help boost motivation.
Types of rewards are important too. I'll do a follow up series on the difference between dopamine-boosting rewards and serotonin-boosting ones.
In the meantime, let's look at Part 6 >