Jamie Li
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