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What Does the Lab Do?

We seek to understand the neural underpinnings of affective (emotional) experience and expression. This endeavor necessarily involves seeking to characterize the neuroanatomical circuits involved: their components, their inputs, and their outputs, as well as the relevant neurochemical modulators (e.g., dopamine). Our progress ultimately relies upon informed use of both psychological theory and neuroscience methodology.

Lab Goals

• To characterize the anatomical trajectories of affective circuits in the brain.
• To characterize how psychopharmacological (drug) manipulations modulate affective experience.
• To understand how the function of these affective circuits is deranged in affective disorders and addiction.
• To understand how psycho- and pharmaco- therapies can normalize deranged affective circuits.
• To understand, by reducing the problem to its individual components, how affective circuitry modulates decision-making and economic behavior
• To innovate and create new technologies and techniques for tracking affective dynamics in the brain.

In short, we've got a lot of very exciting things going on! Our research informs our views of all sorts of compelling aspects of human experience: how we make decisions (it's easy to see how decisions in economic contexts could also apply more broadly to decisions in other facets of life, from morality to what we're having for breakfast), ways in which our heuristics (rules-of-thumb for making decisions) may fail us (don't buy that stock!), how mental illness and mental deficits develop, how they can be diagnosed, and how they can be treated (many, as you may know, involve difficulties in decision-making; therefore the regions we study may be atypical in these disorders). Additionally, we're slowly unraveling a small part of the enormous complexity that is our brain, and that's just plain exciting.

Overview of Research Process

Generally speaking, research in the lab follows this general, intuitive trajectory:

BRAINSTROM → IRB PROPOSAL → PILOT → TWEAK & IMPROVE → RECRUIT SUBJECTS → RUN → PROCESS DATA → ANALYSIS → PUBLICATION → FAME AND FORTUNE

We’ll discuss each of these steps in turn in later sections, but for now let’s talk more specifically about the regions of the brain we’ve been focusing on in recent years. In this section we’ll summarize our findings and give you a sense for what activation looks like and where it’s located.

Areas of the Brain We are Interested In

The reward circuitry we focus on consists of the medial prefrontal cortex, the ventral tegmental area, and the ventral striatum (which consists, in turn, of the caudate nucleus, the putamen, the nucleus accumbens (NAcc), and the fundus, which links the latter two ventrally). These names will mean more to you shortly if you’re unfamiliar with anatomy.

What roles do these structures play in the reward circuitry? Where are they located relative to one another?

Nucleus accumbens (Nacc)

Nucleus accumbens (Nacc) [10, 12, -2]: The NAcc is located inferior to the caudate at the bottom of the internal capsule (the white line separating the caudate from the putamen). This is easiest to see in the coronal view. We see Nacc activation when subjects are anticipating gain, whether it’s anticipation of winning something (money, material goods, tasty food or drink), or simply thinking positively about themselves in the future – in other words, anticipation of an improved future self.

See Knutson, B., Fong, G. W., Adams, C. S., & Hommer, D. (2001). Dissociation of reward anticipation versus outcome with event-related FMRI. NeuroReport, 12, 3683-3687. Other citations go here as well.

Figure 1. Coronal view of the striatum.

Figure 2. Area delineations