Thalamic filter model
202308221605
The thalamic filter model proposes that alterations in the ability of the thalamus to gate information to the cortex through the Cortico-striatal-thalamocortical feedback loop results in an overload of the cortex, where excessive extero/interoceptive stimuli flood the brain and induce ego dissolution, impaired cognitive function, and psychosis (Geyer2008, Vollenweider2001b).
Gating capacities of the thalamus are controlled by the striatum (Vollenweider2001).
- Preller2019 showed that LSD reduces effective connectivity from the ventral striatum to thalamus
This theory is supported by previous work which showed Schizophrenic patients exhibit deficits in PPI and schizophrenic patients show increased functional and effective connectivity between thalamus and cortex
Thalamic gating (aka sensorimotor gating) is thought to be influenced by blockade of NMDA receptors, increasing dopaminergic neurotransmission, and excessively stimulating 5-HT2a receptors.
- Mesostriatal dopaminergic and serotonergic projections provide input to the striatum and are counterbalanced by glutamatergic input from CSTC pathways.
Related Notes
Schizophrenic patients exhibit deficits in PPI
Thalamo-cortical connectivity is modulated by states of consciousness
Q&A
neuroscience
What projections provide input to the striatum? What counterbalances these projections?
{{c1:: Mesostriatal dopaminergic and serotonergic projections}}
{{c2:: Glutamatergic input from Cortico-striatal-thalamocortical feedback loop}}
What changes in CSTC activity does the thalamic filter model predict under psychedelics?
{{c1:: Increased connectivity from thalamus to cortex}} and {{c2:: decreased connectivity from ventral striatum to thalamus}}