Involves three brain regions: the orbitofrontalcortex (OFC), caudate nucleus, and thalamus
The OFC detects worry signals and sends them to the thalamus
The caudate nucleus normally suppresses the worry signals, but in OCD it is impaired so the signals are not suppressed and the thalamus becomes over-excited
This makes the thalamus send strong signals back to the OFC which leads the individual to perform compulsive behaviours and experience anxiety
Nestadt et al. found OCD symptoms in conditions like Parkinson's disease, supporting neural explanations and suggesting biological factors contribute to OCD.
no unique neural symptoms
Co-morbidity between OCD and depression suggests serotonin's role in OCD symptoms may be indirect, through its impact on depression, rather than directly related to OCD.
correlation and causality
The correlation between neural explanations like serotonin and OCD doesn't necessarily imply causation.lower levels of serotonin may not have cause OCD.