Intrinsic connectivity of the human habenula and its relation to negative affect

The human habenula is a small, bilateral, epithalamic nucleus involved in reward processing, providing top- down modulation of dopaminergic and serotonergic midbrain structures. Convergent animal and human research has demonstrated a role for the habenula in learned helplessness and depression, implicating the habenula in the characteristic reward processing dysfunction of depression. However, there is a lack of research supporting this relationship.

Here, we replicate findings from Torrisi et al. (2017), concerning the intrinsic functional connectivity of the habenula at 7T. Then, we extend these findings to a larger sample from the Human Connectome Project and assess individual differences in habenula connectivity with respect to psychosocial well-being, negative affect, and reward processing.

The human habenula displays a robust pattern of intrinsic connectivity across subjects and datasets, including circuitry related to pain, goal, and fear processing, as well as memory, reward, and the Stop Signal Task, which engages motor inhibition. However, this connectivity pattern appears unrelated to mood, social support, personality, or reward processing. This finding is at odds with prior work demonstrating sadness-related habenula connectivity (Ely et al., 2016). Future work should (1) study functional connectivity of the
habenula in a larger sample, to assess the relationship between intrinsic connectivity and factors relating to depression with increased statistical power and (2) assess whether task-based functional connectivity is a better predictor of behavior than resting-state connectivity.