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]
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 . The capacity of STDP to capture temporal relations consistent with causality rather than just correlations has been described by several authors , , , . 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 , rats , non-human apes , children  and human adults  to undertake causal reasoning tasks, i.e. tasks in which good performance cannot be well explained by pair-wise associative learning alone. [...]
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