12
$\begingroup$

Spike timing dependent plasticity (STDP) is a property of synapses that modifies their efficacy based on timing relationships between action potentials in the pre-synaptic and post-synaptic neuron. A pre-synaptic neuron firing in a brief period before the post-synaptic neuron fires potentiates the synapse. When the pre-synaptic neuron fires after the post-synaptic neuron, the synapse is depressed.

Perceptually, we only really see (or hear, or feel) a sequence of events. To infer causation from that requires some mechanism. Kushnir and Gopnik (2005) claim even children do causal inference, which leads me to believe that it is not merely a skill learned later in life.

My question is, does any direct or circumstantial evidence exists that links STDP with causal inference?

References

Tamar Kushnir and Alison Gopnik (2005) Young Children Infer Causal Strength From Probabilities and Interventions. Psychological Science September 2005 vol. 16 no. 9 678-683 (doi: 10.1111/j.1467-9280.2005.01595.x)

$\endgroup$
1
  • $\begingroup$ Just consider that STDP is the lowest level learning mechanism, while causal inference is a higher level one. So even if causal inference is entirely implemented through STDP, their link may not be straightforward to identify. $\endgroup$
    – Pietro
    Commented Feb 16 at 17:01

1 Answer 1

7
$\begingroup$

Fernando et al. (2008) proposed a neuronal mechanism to copy network topologies from one region of the brain to another which is based on Spike Timing Dependent Placticity (STDP) and argue that the mechanism of neuronal copying is a neuronal implementation of causal inference.

Fernando C, Karishma KK, Szathmáry E. (2008) Copying and evolution of neuronal topology. PLoS One 3(11):e3775. [Free PDF]

Abstract

We propose a mechanism for copying of neuronal networks that is of considerable interest for neuroscience for it suggests a neuronal basis for causal inference, function copying, and natural selection within the human brain. To date, no model of neuronal topology copying exists. We present three increasingly sophisticated mechanisms to demonstrate how topographic map formation coupled with Spike-Time Dependent Plasticity (STDP) can copy neuronal topology motifs. Fidelity is improved by error correction and activity-reverberation limitation. The high-fidelity topology-copying operator is used to evolve neuronal topologies. Possible roles for neuronal natural selection are discussed.

In the discussion, the proposed relation between STDP and causal inference is addressed in detail:

[...] In the process of thinking about promising mechanisms, we discovered two serendipitous ancillary benefits of copying. The first was that the mechanism of neuronal copying was a neuronal implementation of causal inference [86]. The capacity of STDP to capture temporal relations consistent with causality rather than just correlations has been described by several authors [65], [87], [88], [89]. However, to our knowledge, STDP has until now not been used in an algorithm to explicitly infer whole causal networks. Considerable attention has been paid recently to the capacity of animals such as New Caledonian crows [90], rats [91], non-human apes [91], children [92] and human adults [92] to undertake causal reasoning tasks, i.e. tasks in which good performance cannot be well explained by pair-wise associative learning alone. [...]

[68] Florian RV (2007) Reinforcement Learning Through Modulation of Spike-Time-Dependent Synaptic Plasticity. Neural Computation 19: 1468–1502.

[86] Glymour C (2003) Learning, prediction and causal Bayes nets. Trends in Cognitive Sciences 7: 43–48.

[87] Abbott L, Nelson SB (2000) Synaptic plasticity:taming the beast. Nature Neuroscience supplement 31178–1183.

[88] Bi G-q, Poo M-m (2001) Synaptic Modification by Correlated Activity: Hebb's Postulate Revisited. Annu Rev Neurosci 24: 139–166.

[89] Gerstner W, Kistler WM (2002) Mathematical formulations of Hebbian learning. Biol Cybern 87: 404–415.

$\endgroup$
1
  • $\begingroup$ Do you think it's possible that STDP and possibly Synfire Chains give us the ability to live 'In the moment - the last 100 mSec or so? I can think of no other set of mechanisms that work in milliseconds and could be responsible for the range of processing needed to keep us aware of the world. $\endgroup$
    – Seti Net
    Commented Oct 3, 2022 at 19:13

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.