Causal mechanisms

One common belief is that emotions contrast with reason: we say someone is being emotional when we believe they are acting unreasonably. But progress in behavioural science and neuroscience has cemented the link between emotions and rational behaviour.

The standard model of decision making in economics has no room for emotions whatsoever, and even behavioural economics treats them as an afterthought. Yet modern neuroscientific evidence shows that emotions drive decisions, to the extent that those whose ability to experience emotions is neurologically impaired are unable to make decisions altogether.

The Somatic Marker Hypothesis was developed by Antonio Damasio and his colleagues in the 1990s. He studied patients who had damage in specific regions of their prefrontal cortexes which didn’t seem to affect their capacity for logical thought, but significantly damaged their ability to feel. This was epitomised by Phineas Gage, an American railroad worker who survived having an iron rod driven through his head in a freak accident, which greatly impaired his ability to make decisions without seeming to affect his working memory, attention, or comprehension.

Damasio ran an experiment where patients who had damage to the same area of their brains as Gage were required to play a simple game that required them to select cards from different decks. Patients won rewards for better cards and some of the decks yielded less, on average, than others. What Damasio showed was that while patients with fully functional brains selected less from these decks over time, those with emotional impairment could not make such a decision, continuing to sample from the bad decks.

It seems that we often make decisions by developing an emotional attachment to a particular outcome. Damasio’s explanation was that we link an outcome to the emotion we experience when it happens. This prevents us from continuing to draw cards from a bad deck because of the disappointment, annoyance, or sadness that we feel when we get a low card.

If we cannot link potential behaviours with emotional outcomes, we lose the ability to steer our behaviour in a desirable direction. While it may be the case that being too emotional, or experiencing certain types of emotions, can lead us to make bad choices, not experiencing emotions at all can lead to the same thing.

Risk as feelings

In a paper, literally titled ‘Risk as Feelings’, (Loewenstein et al, 2001) argued that peoples’ attitudes towards risk are directly driven by emotions rather than cognitive evaluations, as they bypass the cognitive parts of the brain. Images of particular outcomes evoke strong feelings, which leads to an assessment of risk based on those feelings.

Of course, this has its downsides: it seems to be invariant to the actual chance something will happen, which explains peoples’ disproportionate reaction to low probability but vivid events such as terrorist attacks or winning the lottery. This is one explanation for Availability Bias, which we saw in the last activity. It could be that the most easily available memories are those that trigger the biggest emotional reactions.

Overall, there is a growing understanding of emotions as heuristics which provide information that we use to make our decisions. For example, a sudden loud noise may cause fear before we even know where it’s come from, and for good reason, because this fear prepares us to act fast if necessary.

Over to you

What do you think of the Somatic Marker Hypothesis? Do you think that emotions are necessary for us to make good decisions?

References

<sup>1. Damasio AR. The somatic marker hypothesis and the possible functions of the prefrontal cortex. Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences. 1996 Oct 29;351(1346):1413-20.
2. Loewenstein GF, Weber EU, Hsee CK, Welch N. Risk as feelings. Psychological bulletin. 2001 Mar;127(2):267.</sup>