There are many moments in a day where we might have a brief emotional reaction to something – like smiling when we see a baby smile or grimacing when we see a baby crying. We experience continuum of emotions from the very brief in-the-moment reactions to the sustained emotions that impact our behavior at a deeper level. Most studies of emotion focus on those brief reactions, but a new study is offering a new way to look at the impact of sustained emotion on cognition – finding that only longer-term emotional states affected performance on a cognitive task, rather than brief emotional cues.
“We thought examining cognitive control under emotional states of a longer timescale, with experimental control, may provide a more ecologically valid framework with which to understand the effects of real-life emotional situations and/or pathological states of arousal on behavior,” says B.J. Casey of Weill Cornell Medical College, the senior author on the new paper just published in the Journal of Cognitive Neuroscience.
The study modified a go/no go task to have emotional (fearful and smiling faces) and neutral (calm faces) targets for “go” and nontarget cues for “no go.” Participants performed this task under three emotional states: while anticipating a negative event (threat), a positive event (excitement), or no event (neutral). The sustained threat state was the potential to hear a loud, aversive noise, similar to a high-pitched white noise, paired with the image of a megaphone; the positive event was the potential to win up to $100, paired with the image of a slot machine.
The researchers told participants that each condition was associated with a certain colored background on the screen. They also told participants that the probability of an event occurring – either the volume of the noise or the amount of money won – was not influenced by performance, but rather was determined by the computer randomly.
The differences in this design from past studies of emotional influence on cognition were that they measured cognitive performance under changing sustained emotional states, while also examining the effects of brief emotional cues. They also examined the effects of both positive and negative emotional states on cognitive performance relative to non-emotional states. Therefore, they could dissociate emotional state from cue and affects of positive versus negative conditions.
Casey spoke with CNS about the study, its results and how it is laying the foundation for studies of emotion throughout the lifespan, and in adolescence in particular.
CNS: How did you become personally interested in this research area?
Casey: Ali Cohen, the first author on the paper and a neuroscience graduate student, and I have been interested in how emotions impact cognitive control, especially during the period of adolescence. While many laboratories have studied how fleeting emotional images or words impact cognitive control, few if any studies have examined how sustained emotional states impact this capacity or the underlying neural systems involved. So we developed this novel paradigm and first validated the experimental manipulations of emotional state with psychophysiological measures of arousal and self report and then tested the effects of these emotional states on cognitive performance in adults to lay the groundwork for our developmental studies.
CNS: Can you talk a little bit more about how has the influence of emotional states has previously been studied?
Casey: Influences of emotional state have most often been studied using a procedure called mood induction. In mood induction, individuals create and sustain a positive or negative emotional state by recalling emotional autobiographical memories, viewing emotional images or film clips, or reading emotionally charged statements about oneself. This method is effective, but relies on the individual to both induce and maintain the mood state rather than experimental control and typically relies on self report measures for confirming how well the individual did at inducing and maintaining these states.
More recently, studies have induced sustained negative arousal by manipulating the uncertainty or timing of an event or outcome. These studies have primarily focused on anxiety while anticipating an upcoming aversive event or outcome by asking participants questions about their feelings, measuring psychophysiology (such as sweat and heart rate), and examining neural activity during these states.
Still others have used stressed paradigms like the cold pressor test or the Trier social stress task to induce an arousing state and then test cognitive or affective performance. However, few studies have examined cognitive control performance under experimentally controlled emotional states and fewer still have been able to dissociate arousal from valence specific effects on cognitive performance by examining both positive and negative arousal.
CNS: How and why did you choose the particular sustained states of threat or excitement?
We selected our sustained state of threat based on an existing literature showing the effectiveness of instruction in inducing fear. We used an aversive sound as the threat based on previous work in our lab showing its effectiveness as an unconditioned stimulus in Pavlovian fear conditioning in humans. Many research groups have shown that the unpredictable nature of the potential for a negative event, such as a shock or loud noise, maintains a sustained state of arousal in both humans and rodents.
The excite condition was an especially novel one. Just as we exposed the participants to the aversive loud noise before the study, we also exposed the participants to a $100 bill for the excite condition. Both conditions resulted in increased arousal during the experimental conditions relative to the neutral one as measured by skin conductance responses that were supported by the self-report data.
CNS: What were you most excited or surprised to find?
Casey: We were especially excited to see contrasting effects of the duration (brief vs sustained emotion) and valence (positive or negative) of the arousal on performance. It was surprising that brief emotional cues did not impact cognitive performance, only sustained emotional states.
Perhaps less surprising was that positive arousal led to better performance and upregulation of frontoparietal circuitry involved in cognitive control, whereas negative arousal led to worse performance with the absolute worse performance being when there was emotional dissonance among interacting conditions. Specifically, when participants were performing the task under the condition of threat and saw a positive cue (smiling face), we saw performance deteriorate most. For this condition, we observed increased activity in the posterior cingulate cortex (PCC), a region thought to be involved in processing emotions relative to oneself. Studies in primates have suggested that this region may play an important role in recruiting cognitive control circuitry in order to resolve conflict and/or improve performance. Consistent with this interpretation were our results showing positive coupling of activity in the PCC for correct trials with activity in control related prefrontal and parietal regions on these emotionally conflicting trials.
CNS: How would you like to see this work change future study designs?
Casey: We think that by examining cognitive control under emotional states of a longer timescale, with experimental control, that we may provide a more ecologically valid framework with which to understand the effects of real life emotional situations and/or pathological states of arousal on behavior.
Also by using positive and negative states, we think that we prevent emotional states from bleeding into control states. Specifically, had we only had a neutral and negative state, the negative arousal may have been sustained even after the experimental condition, but by having positive mood states interweaved we could prevent a lasting negative bias. Likewise a similar effect could have occurred for the positive excite condition.
Both of these experimental manipulations will be important for future studies.
CNS: What do you most want people to understand about this work?
Casey: Emotions are part of our daily lives and have complex influences on our cognitive processes. Studying behavioral and neural responses under different emotional conditions in healthy adults is a first step toward understanding how emotional experiences may alter behavior in different conditions, such as in pathological states or developmental ages across the lifespan.
CNS: What’s next for you with this work?
Casey: We are currently using our novel emotional states task to investigate how emotional states and cues impact brain and behavior across development with a special interest in adolescence. Adolescence is a time of heightened sensitivity to emotional inputs as well as peak onset of most mental illnesses and increased criminal behaviors. Understanding complex influences of emotions on cognitive control and related neural circuitry during typical development may provide insights into how our emotions affect behavior and brain function and for when they reach “maturity”.
-Lisa M.P. Munoz
