The human palette, according to cognitive psychologist Nancy Etcoff, is capable of detecting sweetness at a ratio of 1:200. Dilute one teaspoon of sugar into 200 teaspoons of water, and we’ll notice. We love sugar! But here’s a confounder for the optimists: the human palette is capable of detecting bitterness at a ratio of 1:2000000. Etcoff’s comparison suggests that, in general, humans are more tuned in to the unpleasant than the pleasant.

“We are both a positive and negative system, and our negative system is extremely sensitive,” says Etcoff. “It is our sentinel. It is there to protect us from danger.”

While a teaspoon of bitters might not fill you with fear, a teaspoon of poison would be another story. Whatever the source, when we sense danger in our immediate environment, our bodies enter “fight or flight” mode, which involves a whole host of physical reactions, including quickened heart rate and breathing, constriction of blood vessels in many parts of the body, and a narrowing of sensory awareness.

Back when we were heaving ourselves out of the primordial soup, this kind of response to threat served us well. Most of the threats we faced then were threats to our physical safety, so it made sense to respond to these threats in a physical way. As Etcoff notes, when confronted with a sabre-toothed tiger, fighting or...flighting is appropriate.

But what about when we’re confronted with life in an affluent, safe, sabre-toothed tiger free city? When the “threat” we encounter is a demanding line manager, or a set-back in an attempt to return to work? In these contexts, our evolutionary stress responses may do us more harm than good.

“Stressed people experience a flood of powerful negative emotions which may include anger, anxiety, and depression,” say Drs Harry Mills and Mark Dombeck, of the MentalHelp.net website. “Some people remain trapped in these negative emotions long after the stressful events that have caused them have passed.”

This has implications for RTW, and for workers’ compensation trends.

Research conducted by Australia’s Centre for Corporate Health into workers’ compensation stress claims found that, in circumstances where non-work factors were prominent in contributing to individual distress, “the impact of pre-existing personality styles was significant, leading a person to be highly vulnerable in the context of ordinary work stressors. Our results show that by far the most vulnerable people to emotional distress are those who possess the trait of emotionality (high emotional reactivity and sensitivity)”.

Some people get scarred by tough times. Other people are more able to bounce back into shape after life has knocked them around. Researchers refer to this ability as emotional resilience.

According to MentalHelp.net, emotionally resilient people tend to:

• Have realistic and attainable expectations and goals;
• Show good judgment and problem-solving skills;
• Be persistent and determined;
• Be responsible and thoughtful rather than impulsive;
• Be effective communicators with good people skills;
• Learn from past experience so as to not repeat mistakes;
• Be empathetic toward other people (caring how others around them are feeling);
• Have a social conscience;
• Feel good about themselves as a person;
• Feel like they are in control of their lives; and
• Be optimistic rather than pessimistic.

Life experiences and possibly even genes help to determine how emotionally resilient a person is, so there is a degree of luck involved. However, emotional resilience is not just a gift; it is also a skill, and it can be learned and fostered.

Psychologist Susan Kobasa has identified three approaches that feed emotional resilience:

• Relishing stress as a challenge, rather than seeing it as paralysing and overwhelming;
• Looking for opportunities to exert personal control, even in situations where some factors are outside of your control; and
• Adopting an active, engaged stance towards life, buoyed up by a sense of purpose.

Organisational, as well as personal factors, will determine how easy it is to adopt these approaches in the workplace.

For example, an injury management system that is very regimented, adopts a “top-down” approach and focuses on the numbers rather than the people is unlikely to encourage workers to exert personal control over their situation, or take ownership of the RTW process.

In contrast, an injury management system that seeks worker input in overcoming barriers to RTW, focuses on the health and wellbeing benefits of getting back to work, and thinks “challenges” rather than “problems” is more likely to foster goal-focused optimism in claimants.

Individual workers may benefit from emotional resilience training. Where appropriate, it is most effective to intervene early.

In August 2010, Medical News Today reported that individuals on long term incapacity benefits because of mental health problems “could be identified by their GPs three years before they stop working”.

That’s right: three years. Three years of “frequent consultations for emotional distress”. Three years wide open with opportunities for interventions that build emotional resilience.

It’s one thing to acknowledge that our “sabre-toothed tiger” stress response might not be appropriate in the contemporary world, and to try and cultivate more suitable ways of dealing with personal and workplace stress. It’s another thing entirely to have three years worth of warning that a threat is lurking, and not do everything in our power to prevent it sinking its teeth in.

Perhaps, in regards to early intervention for those exhibiting signs of low emotional resilience, we could do with a dose of the primordial jitters.

Etcoff's talk on the science of happiness is online at Ted.