Research

Cognitive control describes the strategic use of a current context to flexibly modulate our responses in line with internal goals. The overarching goal of my research is to examine how memory guides cognitive control—namely, how past experiences and internal goals can shape our responses to demands in our environment, particularly those that require a great deal of attention.

My research broadly falls under three main questions:

1. How does learning inform our understanding of cognitive control?

Psychonomics2017
I earned the 3rd place APA Division 3 Poster Award at Psychonomics 2017.

Do our past experiences inform how we respond to situations that require a lot of attentional focus? For example, people might approach a new situation or environment with a heightened sense of attention, because similar environments have proven difficult in the past. In order for this mechanism to work, people would need to bind together a specific control state (e.g., heightened focus of attention) and their memory of the attentionally demanding environment. In this line of research, I examine how learned contextual cues guide strategic adjustment to attentional demands, showing that people can generalize cognitive strategies across similar contexts, and which brain regions support this type of control-learning. For example publications, see:

  • Bejjani, C., Zhang, Z., and Egner, T. (2018). Control by association: Transfer of implicitly primed attentional states across linked stimuli. Psychonomic Bulletin and Review, 25(2): 617-626. http://dx.doi.org/10.3758/s13423-018-1445-6
  • Bejjani, C., Zhang, Z., Dolgin, J., and Egner, T. (Preregistered Direct Replication, Stage 1 in principle acceptance at Psychological Science; registration available here). Disentangling the roles of cue visibility and knowledge in learning cognitive control.
  • Bejjani, C., Tan, S., and Egner, T. (under review at Journal of Experimental Psychology: Human Perception and Performance; preprint available here). Performance feedback promotes learned proactive but not reactive adaptation of conflict-control.
  • Chiu, Y.C., Bejjani, C., Dolgin, J., and Egner, T. (in progress). Neural reinstatement of learned control-states.

2. How do we learn to form context-sensitive stimulus-response rules (task-sets) from interacting with our environment, and how does this impact our memory?

cns2019
I earned a Graduate Student Award at Cognitive Neuroscience Society 2019

In this line of work, I investigate the consequences of learned cognitive flexibility on memory. If people learn to link particular stimuli with specific responses (task-sets) across a variety of environments, do they subsequently remember these stimuli less depending on how the task-set was learned? Can we learn to adapt our cognitive flexibility to match changing attentional demands? What brain regions support learned cognitive flexibility? For example publications, see:

  • Bejjani, C. and Egner, T. (under review at Frontiers in Psychology – Cognition; preprint available here.). Spontaneous task structure formation results in a cost to incidental memory of task stimuli.
  • Sali, A.W., Bejjani, C., and Egner, T. (in progress). Learning cognitive flexibility: Neural mechanisms of adaptive switch readiness.
  • Bejjani, C., Whitehead, P.S., Sali, A.W., Chiu, Y.C., and Egner, T. (preregistration available here). Assessing causal contributions of parietal cortex to learned cognitive flexibility.

3. How can we apply what we know of cognitive control (and learning & motivation) to improve educational as well as public and mental health outcomes?

CNS2016
I earned a Cognitive Neuroscience Society 2016 People’s Choice Poster Award.

Prior to my current research at Duke, I was also involved in learning and motivation research. This research investigated how people performed on attention and learning tasks during and after various social manipulations. For example, in one study, we examined whether neural responses to learning from negative feedback change if participants believe that intelligence is a fixed vs. malleable trait and if they are made to feel less competent. In another study, we examined whether participants who write about past failures vs. the plot of a recent movie experience less stress and do better on an attention task following a psychosocial stressor. I am currently following up with this work by applying the psychological research to educational contexts (i.e., scholarship of teaching and learning). The goal, here, is to understand how people learn so as to inform current educational practices. For example publications, see:

psychonomics2018poster
I earned a Graduate Travel Award at Psychonomics 2018.

In another line of research under this topic, I examine whether individual differences play a role in mental health outcomes. Cognitive control is thought to be altered in many psychiatric disorders, but few studies have examined these deficits in control on a large-scale individual difference level. I recently received a Germinator Grant from the Duke Institute of Brain Sciences to investigate the computational mechanisms underlying individual differences in transdiagnostic deficits in cognitive control. Ask me for more details on this line of work if you’re interested. Although the project is preregistered, it’s still too early to discuss the larger themes, hypotheses, results, etc.

A tangential paper that I worked on before attending Duke examined whether choosing to exert physical effort impacts neural responses to actual effort expenditure. This research can help inform treatments for depression.

  • Sullivan-Toole, H., Bejjani, C., Richey, J.A., and Tricomi, E. (in preparation for Neuroimage; draft available on request). The interplay of choice and effort on outcome processing.

Finally, under this broad goal of applied research, I also examine the real-world consequences of deficits in cognitive control. Multi-tasking is a pervasive public health (and educational) crisis that saps our ability to modulate how we respond to environments in line with our goals. Here, the goal is to apply the research described in Questions 1 and 2 to real-world contexts and test whether research in the lab holds up in our everyday lives as well as ways that we can mitigate the harmful effects of multi-tasking. This research is also in its infancy, so ask me for more details later.

If you have any questions about my research, please feel free to contact me at christina.bejjani AT duke.edu. Thanks so much for visiting!