Compare the functions of the cerebellum and basal ganglia

Sanjay Manohar (Oxford 2015)


 PD - Braak progression. Spillantini: a-synuclein.
     MPTP model, Rx Levodopa + carbidopa, D2 agonists, MAOI, COMTI, anticholinergic
     drug-induced, DBS GPI /STN
 HD huntingtin CAG trinucleotide expansion -> MSN death -> chorea,athetosis,ballismus, hyperkinesia
   Rx Valproate, benzos
 Schiz  Carlsson and Lindqvist 1963 - antipsychotics reduce DA, drug-induced parkinsons
   apathy, neg symptoms 
 Alcohol, MS -> Ataxia, dysdiachokinesis, dysmetria, intention tremor 
Big picture
 necessary (sea squirt)
 integration of all sensory / mnemonic / motivational information


Inputs Limbic system (motivation, memory)
       Cortex (perception)
Output VL thalamus -> motor cortex -> muscles
Modulation of action, Integration of sensory and goal information
Hierarchical control of action


BG Cerebellum
slow fast
deliberation (what to do, when) automation
initiation, release online error correction
motivation coordination
interval timing rhythm, sequence, pattern
value learning state-action learning
cortical input:options, goals locations and intentions
subcx input: RPE sensory feedback (vestib, proprio, visual)
model of contingency model of spatial causation
Most output to Cx Strong spinal output
Limbic, Motor, Cognitive Vestibular, Spinal, Planning


Olds 1958 - self-stimulation of BG is reinforcing. Reward? Pleasure?
MSNs - corticostriatal + dopaminergic input
Direct (substance P) Deniau & Chevalier 1984 Glu in striatum, record VP and VThal.
Indirect (enk) - GPE STN 
Gerfen 1990 =D1/D2. Competition, action selection
Albin & Young 1989, DeLong 1990

Schultz 1997 RPE and RL
Salamone 1994 - DA blockade amotivation



Aalpha fibres -> IO (uncrossed); semicircular canals, 
vestib flocculonodular fastigial, spino vermis interpos, cerebro- hemispheres dentate VLthal
cx -> pons -> mossy -> granule -> parallel fibres -> purkinje -> dentate -> VLthal 
golgi cell neg fb granule. basket cell surround inhibition on purkinje.

spinocbm: Dorsolateral descending systems - action accuracy, tremor
vestib: ventromedial system - walking/standing


Broader issues:

  Both have roles in cognition