Spontaneous eye blink rate (EBR) predicts poor performance in high-stakes situations

Ilse H. van de Groep, Lucas M. de Haas, Iris Schutte & Erik Bijleveld

What was the aim of the study?

Why do people ‘choke under pressure’ in high-stake situations? In the current study, we examine two candidate biological, individual differences that may make people more susceptible to such performance impairments. We consider individual differences in baseline dopamine levels in the midbrain (indicated by spontaneous Eye Blink Rate; EBR) and individual differences in baseline hemispheric asymmetry (measured with electroencephalography; EEG).

How did we study this?

Participants performed an incentivized switch task, where they repeatedly responded to  target characters, which could be letters or digits, depending on the task they were instructed to perform in each trial (Letter task or Digit Task). The trials followed a predictable pattern, alternating between switch trials (where participants had to switch from the Letter to Digit task, or vice versa) and repeat trials (where they did not have to switch tasks). 

Participants first performed a practice block, which was followed by 4 experimental runs (68 trials) where they were asked to improve their performance by approximately 20%. Subsequently, they received the incentive manipulation, and were asked to “retain their performance, or improve their performance even further”. In the loss condition, we told participants that whether they would lose their potential reward (€10) depended on their performance. In the control condition, participants were told that a lottery (after the experiment) would determine whether or not they would lose their payment. After the incentive manipulation, they completed 4 more experimental runs. 

 

Individual differences in eye blink rate?

We first examined whether people with high EBR (indicative of higher levels of dopamine) were more prone to performance decrements than people with low EBR (indicative of lower levels of dopamine). Our findings indicated that people low in EBR were generally capable of improving their performance after the incentive manipulation, whereas people high in EBR were not.

What about hemispheric asymmetry?

We further investigated whether the incentive-triggered effect on performance was moderated by hemispheric asymmetry. However, we did not find any evidence for this idea. 

Take-away

In the current study, we showed that people’s failures to improve their performance (by receiving incentives), are moderated by individual differences in eye blink rate. So, when incentives cause poor performance, this may well be the work of the ascending dopamine pathways.

Cover Image Illustration by Storyset

Description

  • Spontaneous eye blink rate (EBR) predicts poor performance in high-stakes situations

  • Link to Publication

Although the existence of ‘choking under pressure’ is well-supported by research, its biological underpinnings are less clear. In this research, we examined two individual difference variables that may predict whether people are likely to perform poorly in high-incentive conditions: baseline eye blink rate (EBR; reflecting dopamine system functioning) and baseline anterior hemispheric asymmetry (an indicator of goal-directed vs. stimulus driven processing). Participants conducted a switch task under control vs. incentive conditions. People low in EBR were generally capable of improving their performance when incentives were at stake, whereas people high in EBR were not. Hemispheric asymmetry did not predict performance. These findings are consistent with the idea that suboptimal performance in high-stakes conditions may stem from the neuromodulatory effects of dopamine.