Action Selection
Karina Rerichová
CCN
Cognitive science
18.4.2016
Main parts and circuit
a) ↑ Dopamine + ↑Go-pathway + ↓GPi + ↑Thalamus + ↑Frontal cortex = ACTION
b) ↓ Dopamine + ↑NoGo-pathway + ↓GPe+ ↑GPi + ↓Thalamus = ↓ Motor Response
Training model
LEARNING
 occurs during this phasic DA signal, so that synapses between
active cortical and striatal Go units are strengthened,
whereas those for NoGo units are weakened
 Probabilistic selection task - „trial – error“
TASK process:
When a stimulus S1 is presented, the network can respond by:
 choosing A (selecting Response R1) – 80 % reward – DA burst
 choosing B (selecting R2) – 20 % punished – DA dip
+ transfer phase:
Allow the model to choose between paired combinations of all the
responses according to learning process:
 R1 vs. R3 or R4 – network chooses between A and C or D
(60:40 – reward-punish)
 R2 vs. R3 or R4 – network chooses between B and C or D
RESULTS
Parkinson´s disease
 degenerative disorder of the central nervous system
 mainly affecting the motor system
 Symptoms:
 shaking, rigidity, slowness of movement and difficulty with
walking and gait,
 thinking and behavioral problems
 sensory, sleep, and emotional problems
References
 GBD 2013 Mortality and Causes of Death, Collaborators (17 December
2014). "Global, regional, and national age-sex specific all-cause and causespecific mortality for 240 causes of death, 1990–2013: a systematic analysis for
the Global Burden of Disease Study 2013.". Lancet 385: 117 71.
doi:10.1016/S0140-6736(14)616822PMC: 4340604. PMID 25530442.
 O´Reilly et al. 2014. Computational Cognitive Neuroscience.
Doi:
psych.colorado.edu/oreillyhomepage
 Goodman, Catherine C., MBA, PT, Kenda S. Fuller, PT, NCS, and
William G. Boissonnault, MS, PT. Pathology Implications for the Physical
Therapist. Second Edition ed. Philadelphia: Saunders, 2003. Print.
 "Basal Ganglia (Section 3, Chapter 4) " Neuroscience Online: An Electronic
Textbook for the Neurosciences | Department of Neurobiology and Anatomy - The
University of Texas Medical School at Houston. The University of Texas Health
Science Center at Houston (UTHealth)., 1997. Web. 03 Dec. 2012.
Thank you for your attention!