Jamie Li

Obsessive Compulsive Disorder(OCD) is a debilitating disorder in which one has constantly recurring negative thoughts that create anxiety, followed by repetitive compulsions in order to relieve anxiety As a psychological

problem? Or maybe a neurological

problem? This implies that there is

an emotional AND a motor component of OCD

https://www.youtube.com/watch?v=vnKZ4pdSU-s

Orbitofrontal Cortex (OFC) “mistake feeling”

Cingulate Error detection Feelings of dread and anxiety

Basal Ganglia Habits!

Orbitofrontal Cortex• Mistake Feeling• Evaluation of the reward

of the stimulus• Connections:

• All sensory modalities

• NUCLEUS Accumbens!

• Anygdala, Hippocampus, hypothalamus

• Well positioned to serve as an interface b/w emotion&motivationwith inputs from the external world

“Error and conflict detection”

“Feelings of Dread and Anxiety”

Connections: Hippocampus Amygdala Limbic Cortex

Part of a system that deals with emotion formation and processing, learning, and memory E.g. Actions induced a

positive emotion, so we have learning!

One of the many loops running through BG

Habits! Chunking of behavior

Hyperactivity causes overproduction of habits? Sounds like OCD

The BG works as a series of inhibitory loops

Direct Pathway: initiates movement, 2 inhibitory pathways = positive movement Striatum inhibits Gpi, which

releases its inhibition on thalamus, thus allowing movement

Indirect Pathway: inhibits movement, 3 inhibitory pathways = negative movement Striatum inhibits Gpe, which

releases its inhibition on STN, STN is now free to excite Gpi, which potentiates its inhibition on thalamus, thus decreasing movement

1 proposed hypothesis is that: The OFC evaluates the reward of a certain stimulus

and creates the mistake feeling This triggers the Cingulate Gyrus, which is highly

connected with emotional structures such as the amygdala to produce feelings of dread and anxiety (AFFECTIVE COMPONENT)

The OFC and Cingulate hyperactivate the striatum, which creates the desire to complete compulsions in order to relieve anxiety (MOTOR COMPONENT)

Psychological Serotonin (SSRI’s) Exposure Therapy Cognitive Behavioral Therapy

Neurological Optogenetics

Comorbid with Tourettes! Problem with the motor loop of the basal ganglia Over-generation of motor component, results in

motor tics and vocalizations

https://www.youtube.com/watch?v=e8HtTb0Vk_o