What generate our
habitual and controlled behavior?

Automatic and voluntary behavior have been issued for long time 
in many fields including psychology, philosophy, theology as well as cognitive neuronscience.
My goal is to reveal the brain circuits encoding the memories for the automatic and voluntary behaviors and manipulate these behaviors for human. 
  Fig.1 MRI reconstruction of primate basal ganglia and their parallel circuits
(Kim and Hikosaka, 2015 Brain)
3D structure of the Caudate nucleus and Tracer injection sites
(from Frontiers Neuroanatomy, 2013 and 2017)


  Let’s see the automatic eye movements to good or bad object 
after long-term learning but with no direct reward outcome!
(Kim and Hikosaka, 2013 Neuron)
Movie 1. Eye movement to previously rewarded object (good).
DW-data-saccadet_to_badObj                 Movie 2. Eye movement to previously non-rewarded object (bad).

To find the whole circuits and their mechanisms for automatic and voluntary behavior,
my lab will use various kinds of techniques including tracer injection, genetics, electrophysiology and MRI.
I showed a specific dopamine neuronal circuit for the habitual behavior.
A specific circuit controls the automatic behavior.
(Kim et al., 2015 Front. Neuroana.)
Fig.2 Automatic behavior-specific circuit (red) in substantia nigra.
Habit-specific dopamine neurons are labeled in orange color!

Along the same line of my research,

I finally found a new type of dopamine neuron which teaches the habitual behavior specifically (Frontiers in Neuroanatomy 2013 and Cell 2015).
My new findings for habitual behavior will give new ideas how the primates behave and how to treat brain disorders.
Fig.3 Two different types of dopamine neurons in substantia nigra (Cell, 2015)
If we reveal the whole circuits and their mechanisms, 
we can manipulate the brain and use the knowledge for everyone.