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Hardware/Software Models of Brain Like Self-Repair. Liam McDaid, Jim Harkin & Muhammad Naeem (Ulster) John Marsland (Liverpool). SNN based Brain Model. Endocannabinoid Mediated Self Repair. DSE is very local: 2-AG travels ~20nM.
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Hardware/Software Models of Brain Like Self-Repair Liam McDaid, Jim Harkin & Muhammad Naeem (Ulster) John Marsland (Liverpool)
Endocannabinoid Mediated Self Repair • DSE is very local: 2-AG travels ~20nM. • e-SP is local and far reaching: astrocyte releases glutamate at all contacted synapses. • e-SP signalling pathway: proposed mechanism of self repair for damaged or low PR synapses. • If neuron does not fire due to damaged synapse no 2-AG emitted (No DSE). However, PR increased via astrocyte stimulation by neighbouring neurons releasing 2-AG. Navarrete, M., & Araque, A (2010). Endocannabinoids Potentiate Synaptic Transmission Through Stimulation of Astrocytes, Neuron, 68(1), 113-126.
2-AG (DSE) 2-AG (DSE) e-SP e-SP 2-AG 2-AG 2-AG (DSE) Endocannabinoid Mediated Self Repair Healthy State After Damage
2-AG (DSE) e-SP 2-AG Endocannabinoid Mediated Self Repair
Endocannabinoid Mediated Self Repair Self-repair in a Bi-directionally Coupled Astrocyte-Neuron (AN) System based on Retrograde Signalling, Special Topic: Frontiers in Computational Neuroscience, 26 September 2012
Need to consider Probability of Release in STDP rule - used the BCM rule for now but need to re-visit this again δω ωp δt ωd
VDD 10V Cluster C2 VPN1 VR X FGn FG1 FG2 N2
Conclusion • Implemented an self-repairing SNN • Based on an “astro-centric” topology • Targeting IEEE TNNLS plus a conference paper (ICANN 2014) • Next step is a demonstrator of Self-Repair: EPSRC bid
Acknowledgements Dr. John Wade (Ulster) eFuturesXD