+Orbitofrontal cortex tracks positive mood in mothers viewing pictures of their new born infants.

J.B. Nitschke, E.E. Nelson, B.D. Rusch, A.S. Fox, T.R. Oakes & R.J. Davidson

Interpreted by Kelsey Andison

+Introduction

Little progress in tracking the circuitry governing positive emotion.

Most previous research – almost exclusively : reward paradigms & pharmacological agents with nonhuman mammals.

Recent human studies – identify brain substrates associated with reward and drug abusers - limited sampling of positive emotion

+How to elicit genuine positive emotion?

Some studies asked subjects to re-experience happy life events.

Not been previously investigated – positive affect in a mother’s relationship with her infant.

Positive emotion in maternal attachment = warmth, joy, fulfillment = post-goal attainment positive affect

+Method- Participants/Stimuli

6 Moms (3-5 month infants) no postpartum depression

6 weeks prior came in for photo shoot – infant and friend of mom (same gender as infant) photographed

Adult photos = Control Infant photos = Stimuli

Mood ratings – 9 point scale for 5 descriptorsHappy, Loving, Motherly/Nurturing, & Excited

Experimental method

+Results

Mood – more pleasant after viewing own infant versus unfamiliar infant

Bilateral OFC activation to own infant versus unfamiliar infant. Most activation shown in left OFC.

Positive correlation between OFC activation and pleasant mood ratings.

+Results

1st Infant scan 2nd Infant scan

+Results – Key Findings

Pleasant Mood = positively correlated with orbitofrontal cortex activation

Bilateral OFC activation in all subjects when viewing own infant compared to baseline & unfamiliar infants.

+Discussion/ Interesting Points

Therefore – OFC implicated in positive emotions

Based on own vs. unfamiliar infants – OFC tracks intensity of positive emotion/mood

OFC in maternal attachment involves appreciation and enjoyment rather than pursuit of desired objective.

+Strengths & Limitations

Very clearly laid out method – could be easily replicated

Uses an actual positive emotion evoking stimuli not just a reward.

Too small of a sample size

Strengths Limitations

+My Opinion

Overall, I liked the paper.

- well explained and very detailed

Easy to understand the why and how.

Interesting perspective on positive emotion – using a situation where there is an abundance of positive emotion.

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Questions?