Presentation is loading. Please wait.

Presentation is loading. Please wait.

Kaushik Majumdar Center for Complex Systems and Brain Sciences

Published byMaría Luz Contreras Modified over 5 years ago

Similar presentations

Presentation on theme: "Kaushik Majumdar Center for Complex Systems and Brain Sciences"— Presentation transcript:

1 Astrocyte Dynamics: Towards a More Complete Picture of Computation in the Brain
Kaushik Majumdar Center for Complex Systems and Brain Sciences Florida Atlantic University

2 Some Compelling Facts Schummers-Yu-Sur paper in Science reports astrocytes, like neurons, respond to visual stimuli including orientation and spatial frequency. Astrocytes secrete thrombospondin that triggers synapse formation (structural aspect of neuronal networks).

3 Compelling Facts (cont.)
Astrocytes can secrete transmitters like glutamate and ATP and can have excitatory or inhibitory effects on neurons (functional aspect of neuronal networks).

4 Tri-Partite Synapse Synapse Presynaptic Neuron Postsynaptic Neuron
Gliotransmitter release Gliotransmitter release Astrocyte Ca2+ increase

5 Neuronal-Glial Phase Relationship

6 Neuron to Astrocyte Communication: Example

7 Astrocyte to Neuron Communication: Example

8 Astrocyte to Astrocyte Communication: Example

9 Mechanism

10 Computation by Neurons, Synapses and Astrocytes
Synaptic plasticity can convey different messages to the postsynaptic neuron of the same spike train generated by the presynaptic cell. Synaptic plasticity is mediated by neuronal firing. Astrocytes control synaptic transmissions and new synapse formation.

11 Computational Paradigm
Ionic Diffusion Potentiation Chemical Synapse Neuron Ca2+ increase Ca2+ increase Astrocyte Transmitter Diffusion Action

12 Prevailing Scenario Currently computation in the brain amounts to neural computation alone that is, only ionic diffusion potentiation (the Hodgkin-Huxley model or various derivatives of that).

13 Future Scenario In view of the synaptic computation (Abbott and Regehr in Nature of 14 Oct, 2004) and astrocytic computation (PhD thesis of Suhita Nadkarni, Ohio State University, 2005) in order to get a more complete picture of brain computation neurotransmitter diffusion actions will have to be incorporated alongside the ionic diffusion potentiation.

14 Transmitter Actions on Astrocytes
Glutamate release mGluR Ca2+ IP3 Ca2+ waves

15 Astrocyte Dynamics: IP3

16 Astrocyte Dynamics: IP3R

17 Astrocyte Dynamics: Ca2+ Flux

18 Ca2+ Conservancy in Cell

Download ppt "Kaushik Majumdar Center for Complex Systems and Brain Sciences"

Similar presentations

Synaptic Cleft: Information Transfer

Synaptic Cleft: Information Transfer
SYNAPSES AND NEURONAL INTEGRATION

SYNAPSES AND NEURONAL INTEGRATION
Neuronal signalling- 3 lectures Dr Bill Phillips, Dept of Physiology Synapses and neuronal signalling Local signalling in neurons Excitability and Initiation.

Neuronal signalling- 3 lectures Dr Bill Phillips, Dept of Physiology Synapses and neuronal signalling Local signalling in neurons Excitability and Initiation.
Synapses Figure 11.17.

Synapses Figure
Effects of Excitatory and Inhibitory Potentials on Action Potentials Amelia Lindgren.

Effects of Excitatory and Inhibitory Potentials on Action Potentials Amelia Lindgren.
Synapses are everywhere 10 11 neurons 10 14 synapses Synapse change continuously –From msec –To hours (memory) Lack HH type model for the synapse.

Synapses are everywhere neurons synapses Synapse change continuously –From msec –To hours (memory) Lack HH type model for the synapse.
Structure and Control of Movement

Structure and Control of Movement
How does the mind process all the information it receives?

How does the mind process all the information it receives?
Neural communication How do neurons send messages to each other?

Neural communication How do neurons send messages to each other?
The Integrate and Fire Model Gerstner & Kistler – Figure 4.1 RC circuit Threshold Spike.

The Integrate and Fire Model Gerstner & Kistler – Figure 4.1 RC circuit Threshold Spike.
Chapter 11-Part II Biology 2121

Chapter 11-Part II Biology 2121
1 Session 5 The Neuron II: Synaptic Transmission PS111: Brain & Behaviour Module 1: Psychobiology.

1 Session 5 The Neuron II: Synaptic Transmission PS111: Brain & Behaviour Module 1: Psychobiology.
Chapter 8c Neurons: Cellular and Network Properties.

Chapter 8c Neurons: Cellular and Network Properties.
Ch. 12 Nervous Tissue. Objectives Understand how the nervous system is divided and the types of cells that are found in nervous tissue Know the anatomy.

Ch. 12 Nervous Tissue. Objectives Understand how the nervous system is divided and the types of cells that are found in nervous tissue Know the anatomy.
Neurons Structure and Conduction of a Nerve Impulse.

Neurons Structure and Conduction of a Nerve Impulse.
synaptic plasticity is the ability of the connection, or synapse, between two neurons to change in strength in response to either use or disuse of transmission.

synaptic plasticity is the ability of the connection, or synapse, between two neurons to change in strength in response to either use or disuse of transmission.
The Action Potential & Impulse/Signal Propagation Learning Objective Be able to describe what a synapse is. Be able to describe how an action potential.

The Action Potential & Impulse/Signal Propagation Learning Objective Be able to describe what a synapse is. Be able to describe how an action potential.
BME 6938 Neurodynamics Instructor: Dr Sachin S Talathi.

BME 6938 Neurodynamics Instructor: Dr Sachin S Talathi.
Copyright © 2010 Pearson Education, Inc. The Synapse A junction that mediates information transfer from one neuron: To another neuron, or To an effector.

Copyright © 2010 Pearson Education, Inc. The Synapse A junction that mediates information transfer from one neuron: To another neuron, or To an effector.
NEURAL TRANSMISSION Differentiate neurons and glial cells. Differentiate the 3 types of neurons. Identify the parts of the neuron. Explain how the action.

NEURAL TRANSMISSION Differentiate neurons and glial cells. Differentiate the 3 types of neurons. Identify the parts of the neuron. Explain how the action.

Similar presentations

Ads by Google