Bernal S D_2010.pdf - University of Plymouth

6.2. COMPARISON WITH EXPERIMENTAL EVIDENCE
• A real-time hardware implementation using large field-programmable gate arrays (FP-
GAs) or other parallel-compuling systems such as the SpiNNaker (Jin et al, 2010). The
proposed model is well suited to parallel distributed implementations such as those of­
fered by hardware chips.
Reducing the simulation time would allow one to systematically explore the different param­
eters of the model and gain deeper insights into the approximations, sampling methods and
results obtained by the simulations.
6.2 Comparison with experimental evidence
The proposed model is consistent with experimental evidence ranging from neuron physiology
to anatomical data, and with several experimenlally-grounded cortical theories. These are listed
below:
• Widely accepted principles of object recognition in the ventral path, as supported by
anatomical, biological, physiological and psychophysical data (Cadieu el al. 2007, Hung
el al. 2005, Knoblich et al. 2007, Kouh and Poggio 2008, Masquelier et al. 2007, Riesen-
huber and Poggio 1999, Serre et al. 2005a, 2007b, Serre and Rlesenhuber 2004, Walther
and Ktx:h 2(M)7, Yu ei al. 20O2). The Bayesian network reproduces the UMAX model op­
erations and structure, which have been shown to capture these principles, and achieves
invariant object categorization. See Section 2.1.2 for further details.
• The parallel, distributed and hierarchical architecture of the cortex is also reproduced
by the inherent structure of Bayesian networks and belief propagation (Pearl 1988, Rao
2004, Lee and Mumford 2(X)3, George and Hawkins 2009). Similarly, ihe homogeneous
internal structure of cortical columns (Ihe canonical microcircuit) is comparable to the
homogeneous internal operations (belief propagation) of each Bayesian node (Fri.ston
and Kiebel 2009, George and Hawkins 2009. Steimer et al. 2009, Lilvak and Ullmaii
2009). Possible cortical mappings of belief propagation and biologically plausible imple­
mentations have been thoroughly reviewed in Sections 3.4,1 and 3.4.3. Furthermore, an
abundant body of evidence arguing forlhe. more general. Bayesian brain hypothesis was
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