This model comes from a [computational approach to interpreting cognitive science.][(Imagining the brain as a kind of computer, and using that to make predictions.)] To try to explain emotion, the reasoning goes like this: we commonly split approaches in programming between algorithms and heuristics. Since emotions behave like heuristics, and most other thought processes do not, perhaps that is what emotion is, explaining its purpose and its drawbacks.
What is a heuristic and its purpose?
Heuristics are best described in tandem with algorithms. Both are (processes that return answers!Processes.)(process-definition), but the difference is: algorithms keep going until you find the answer, while heuristics do just enough to arrive at a reasonable guess. In order to make reasonable guesses, a heuristic must be a learning, trial-and-error process.
To be more clear, a process in this case refers to a set of instructions a human (or computer, or whatever) can follow in order to make a decision. No matter what, every decision you make must come from either an algorithm or a heuristic, using this definition.
Algorithms are the best choice when you have unlimited computation time, but heuristics can be necessary when working under a time constraint or when the problem is too unwieldy to easily code a precise algorithm. (For example...)(virus-detection)
Virus detection for antivirus software uses heuristics both to meet time constraints and lessen programming time. After all, the longer detection takes, the less processing time the user has for their tasks, and coding a "perfect" analysis is really unwieldy.
(Note: Set aside certain psychology results, for now.)(heuristics-psychology)
Though I'm using the same definition as you would in psychology, I'm not going to refer to any specific results or descriptions from that field, such as these well-known heuristics. I'm taking the computer science applications alone and using them to rethink the way we look at emotion.
How could emotion be heuristic?
Consider the emotion of satisfaction. Certain interactions with things or people can make you satisfied or dissatisfied, and you tend to continue satisfying interactions and stop dissatisfying ones. This is an easy, effective heuristic, guessing at the answer to "Will doing this be good for me?"
This question is well-suited for a heuristic approach because there is usually not enough information to know the answer for certain, and the information you do have can be vast. Instances of uncertainty include choosing to visit a museum without knowing exactly what's inside and choosing to interact with someone without knowing exactly what they'll say or do. As for the vastness, basing your decisions off of previous experience makes sense, but waiting to greet a friend until you've remembered every previous interaction with them does not.
What heuristic process does emotion use?
There are a number of details we can deduce, which I'll walk through, using the emotions of satisfaction and dissatisfaction as examples. I'm only going over the things that seem to apply to every emotion, so feel free to try to think of examples of the same things with different emotions. (Note that it is likely for different processes to be used by different emotions or different people, especially when some people don't seem to experience or rely on certain emotions.)
(Emotion has an accumulation on a scale.)(emotion-accumulation)
For example, when someone does something you don't like, you won't completely avoid them unless they do it more. The dissatisfaction seems to build up, and you become less and less likely to choose to interact with them. Another example is when you must choose between two satisfying options. To decide, you may compare the satisfaction you feel when imagining the choices, implying that you can put satisfaction on some sort of scale.
(Emotion is often the first thing felt during recall.)(emotion-first-felt)
There are many examples of this, from being satisfied at the mention of your last birthday party without remembering exactly what happened in it, to declining to go to a store that felt dissatisfying without remembering why you dislike it. A more interesting example is when this conflates emotions, such as when a good friend does something very dissatisfactory, and then the mere mention of the friend feels both good and bad at once.
(Emotion and memory recall affect each other.)(emotion-attached-to-memory)
It's clear that remembering a satisfying event makes you feel satisfied, but it's also possible for feeling satisfied to remind you of satisfying events. Also, the inverse can be true, when you feel very dissatisfied and find it difficult to remember recent satisfying events.
(Emotion and experience affect each other.)(emotion-experience)
Once again, it's clear that experience affects emotion; the interesting thing is that it goes both ways. An example of this is with nostalgia, when someone keeps recalling certain events with satisfaction, and over time, the memory itself changes to become more satisfactory. (Note...)(note-ptsd)
This is a kind of positive feedback loop that is easy to form and can be detrimental. For instance, traumatic events can give rise to PTSD, where anything associated with the event immediately triggers negative emotions that can be even worse than those experienced during the event.
It can be harder to notice how emotion also affects experience immediately, as the event occurs. For that, I recommend something like walking through a park twice, the first time periodically pausing to recall a dissatisfying event, the second a really satisfying one. What you notice each time will tend to be different in different emotional states, even though the same things may be happening around you.
Given these properties, the model I use for emotion is the following. Each experience, as it happens or is remembered, affects and is affected by the current emotion. Then the experience is stored in memory, both with that emotion attached and with the memory attached to that emotion. The emotion stored is the sum of all experienced emotions on their various scales, to allow conflation.
The purpose of this entire process is to allow quick decision-making based on past events without having to explicitly recall each event in entirety, which is why the emotion is recalled first. This purpose also applies to subconscious decisions: You cannot perceive everything at once, so what you focus on and what gets saved to memory is affected by emotion. Since emotion is decided very quickly in the moment, upon later recollections, it may need to be altered. And lastly, it only makes sense to conflate emotions, since every bit is important for the decisions; there's rarely a case where the memories tied to one emotion should cancel out or overwrite another.
What are some drawbacks?
There are numerous pitfalls for heuristics in computer science, and the same concerns apply to emotions:
(The heuristic should have a well-founded theory.)(heuristic-well-founded)
Since emotion is the product of an evolutionary trial-and-error, there's no firm theory behind it. In particular, it seems that everyone has different emotional schemas, and every one of them has flaws in dealing with certain situations.
(Sometimes a heuristic suitable for one case is overgeneralized to an unsuitable case.)(heuristic-overgeneralized)
I'm sure everyone's encountered a time an innocent phrase triggered anger or sadness, even though the current context bears no resemblance to the time when the phrase deserved that response. (e.g., "You people? What do you mean, 'you people'?!")
(A heuristic may never find the goal, perhaps by skipping back and forth between two nodes.)(heuristic-nonterminating)
I've found that in certain emotional states my mind tends to get caught in "mind loops", going back over the same memories or internal conversations over and over. The term "mind/mental/thought loop" seems to be generally understood for meaning something along these lines, so I think it's safe to say many others experience this.
Note, however, that some mind loops are conscious and logical, actually recalling the events for each step, where an emotional mind loop would cycle through the emotional tags without needing to recall the actual memories. For example, a few anger-inducing memories can make you angrier over the course of the day as you repeatedly remember they happened, without you having to actually remember what happened.