Title: Burstprop: a mechanistic theory for the orchestration of learning in cortex
Abstract:
Synaptic
plasticity
is
believed
to
be
a
key
physiological
mechanism
for
learning.
It
is
well
established
that
it
depends
on
pre-
and
postsynaptic
activity.
However,
models
that
rely
solely
on
pre-
and
postsynaptic
activity
for
synaptic
changes
have,
so
far,
not
been
able
to
account
for
learning
complex
tasks
that
demand
credit
assignment
in
hierarchical
networks.
Burstprop
is
a
theory
that
exploit
the
fact
that
synaptic
plasticity
is
regulated
by
high-frequency
bursts
of
spikes,
it
allows
pyramidal
neurons
higher
in
a
hierarchical
circuit
to
coordinate
the
plasticity
of
lower-level
connections.
Using
simulations
and
mathematical
analyses,
we
have
demonstrated
that,
when
paired
with
short-term
synaptic
dynamics,
regenerative
activity
in
the
apical
dendrites
and
synaptic
plasticity
in
feedback
pathways,
a
burst-dependent
learning
rule
can
solve
challenging
tasks
that
require
deep
network
architectures.
To
end,
I
will
provide
a
discussion
on
the
biological
plausibility
of
burstprop
as
a
theory
for
the
coordination
of
synaptic
plasticity
in
the
brain.
Speaker's Website: http://www.neurodynamic.uottawa.ca/neuralcoding/index.html