by Paul Thagard
The mind does not just have concepts and beliefs, but also attaches values to them. When the brain is representing some aspects of the world, it is simultaneously valuing it. The brains reaction to sensory stimulus comes about through the dynamic interaction of external sensory perception, internal sensory perception, cognitive appraisal, and positive and negative valuation. Overall appraisal of how a situation fits or fails to fit with your goals comes about because of parallel processing through the firing activity of the neural populations as they interact. Value naturally enters the picture because the neural populations involved in the representation of the situation and personal goals include ones in areas such as amygdala, the nucleus accumbens, and the orbitofrontal prefrontal cortex that help to encode positive and negative features. An overall assessment of value comes about when parallel constraint satisfaction combines the features of the situation, goals, and values to compute the overall emotional coherence of the situation. The hippocampus plays a major role in memory and interpreting situations in the context of previous experience.
Emotions are patterns of activity in multiple brain areas that integrate cognitive appraisal and bodily perception, producing conscious experiences and guiding action. It should now be clear how religious faith can be a kind of emotional consciousness. When people maintain that their faith assures them of the existence and goodness of God, their certainty derives from an immense feeling based on emotional coherence of those beliefs with their personal goals, not from an inference to the best explanation based on evidence.
A feeling such as happiness or fear can provide a concise summary of the complex unconscious evaluation by the constraint satisfaction of the advantages and dangers of a situation. Feelings provide succinct information about anticipated benefits and risks, and therefore foster quick and effective action. Other likely advantages of emotional consciousness are social, providing a more direct way of understanding the emotional states of others.
There are at least five affective afflictions, ways our emotions can seriously skew our thinking away from rationality: motivated inference, self-deception, weakness of will, depression, and manic exuberance.
- Inferences are motivated when they are affected by our personal goals, as when people try unverified medical treatments in the hope of improving their physical conditions. Such motivated inferences are clearly emotional, because the belief that the treatment will work is based on the valuation attached to the goal of getting better rather than on evidence efficacy. Most of us are prone to believe things that make us happy.
- Motivated inference can contribute to self-deception, which occurs when you form a belief even though you have evidence against it. Our thinking has no direct access to our huge numbers of neural representations and processes, so it is not surprising that we can deceive ourselves by making motivated inferences to some conclusions that available evidence should lead us to reject.
- More common affective affliction is weakness of will, which occurs when you find yourself doing something that you know is not in your best interests. Familiar cases are eating fattening foods, drinking too much alcohol, gambling more than you can afford, having inappropriate sex, or lazily watching television instead of completing some overdue work.
Weakness of will is fostered by the operation of separate neural systems for immediate and delayed rewards. The midbrain dopamine system is preferentially activated by decisions involving immediately available rewards, whereas regions of the lateral prefrontal cortex and the posterior parietal cortex are engaged uniformly by long- and short- term choices. People are particularly prone to make bad choices when they are tired, stressed, and presented with tempting sensory stimuli. The prefrontal cortex says no, but the nucleus accumbens says: yes, yes, yes!
- Many people suffer occasionally chronically from depression, a state of pervasive sadness, in which one finds it hard to see how anything can have any value at all. A depressed person may loose the ability to find any enjoinment in previously pleasant activities and may slump into inactivity.
Cognitive therapy is often effective by helping people to change their beliefs about the hopelessness of their conditions. It can complement drug therapy that changes the brain by affecting levels of neurotransmitters such as serotonin and increasing the generation of new neurons in the hippocampus.
So what are we to do if we want to be both rational and emotional? I propose this rule: feel emotions, not too strongly, mostly happy. We need emotions to motivate and guide our inferences, but emotional intensity should be proportionate to their relevance to our goals, which must be coherent with our overall interests and evidence-based beliefs. Hence emotions construed as a combination of bodily perception and cognitive appraisal can be altered by behaviors and treatments that affect one or both of these.