Colloquia
are
generally
on
Tuesdays
at
3:30
p.m.,
once
per
month.
They
are
usually
held
in
the
Centre
for
Theoretical
Neuroscience
(CTN)
seminar
room
(Psychology,
Anthropology,
Sociology
building
(PAS),
Room
2464;
exceptions
will
be
noted).
Abstracts
are
posted
as
available.
If
you'd
like
to
be
on
the
mailing
list
announcing
these
events,
please
sign
up
here.
Here is a list of our upcoming speakers for the 2016-2017 academic year:
October 18, 2016 - Robert Jacobs (University of Rochester)
December 6, 2016 - Julio Martinez-Trujillo (Western University)
February 28, 2017 - Richard Staines (University of Waterloo)
March 13, 2017 - Ed Connor (Johns Hopkins University)
March 28, 2017 - Gunnar Blohm (Queens University)
April 5, 2017 - Waterloo Brain Day (11th Annual)
Date:
Tues.,
Oct.
18,
2016
Location:
PAS
2464
Time:
3:30
pm
Speaker: Robert
Jacobs
(University
of
Rochester)
Title: From
Sensation
to
Conception:
Theoretical
Perspectives
on
Multisensory
Perception
and
Cross-Modal
Transfer
If a person is trained to recognize or categorize objects or events using one sensory modality, the person can often recognize or categorize those same (or similar) objects and events via a novel modality, an instance of cross-modal transfer of knowledge. How is this accomplished? The Multisensory Hypothesis states that people extract the intrinsic, modality-independent properties of objects and events, and represent these properties in multisensory representations. These representations mediate the transfer of knowledge across modality-specific representations. In this talk, I'll present two projects evaluating the Multisensory Hypothesis using experimental and computational methodologies. The first project examines visual-haptic transfer of object shape knowledge, and the second project examines a novel hidden (latent) variable model of multisensory perception. I'll also consider implications of an experiment demonstrating generalization from perception to motor production for our understanding of cross-modal transfer.
Date:
Tues.,
Dec.
6,
2016
Location:
PAS
2464
Time:
3:30
pm
Speaker:
Julio
Martinez-Trujillo
(Western
University)
Title:
Mechanisms
of
Working
Memory
Coding
in
the
Primate
Brain:
From
Single
Neurons
to
Neuronal
Ensembles
Working memory is the ability to maintain and manipulate information that is not available to the senses during short time intervals. It is currently thought that working memory arises from the sustained activity of neurons selective for spatial locations, features, and complex objects in different areas of the primate brain. One issue that has been a matter of debate is what is the role of different brain areas in working memory coding. I will present data from electrophysiological recordings along the primate visual dorsal pathway during working memory tasks and compare the fidelity of working memory representations of spatial locations and features by single neurons amongst these areas. I will then focus on the prefrontal cortex and elaborate on how interactions between neurons shape the coding of working memory within this area, and how measurements of correlated activity can reveal important aspects of the dynamics underlying working memory coding. I will finally elaborate on the implications of these different findings for current models of working memory.
Date:
Tues.,
Feb.
28,
2017
Location:
PAS
2464
Time:
3:30
pm
Speaker:
Richard
Staines
(University
of
Waterloo)
Title:
Crossmodal
Influences
in
Somatosensory
Cortex:
Interaction
of
Vision,
Touch,
and
Attention
Date:
Mon.,
Mar.
13,
2017
Location:
PAS
2464
Time:
3:30
pm
Speaker: Ed
Connor
(Johns
Hopkins
University)
Title:
Shape
Information
in
the
Primate
Brain
We
study
neural
coding
of
shape
in
the
ventral
pathway
of
primate
visual
cortex.
Because
natural
shape
is
a
virtually
infinite
domain,
neural
coding
is
sparse
and
difficult
to
define.
To
compensate,
we
use
genetic
algorithms
to
focus
stimulus
sampling
on
the
response
ranges
of
specific
neurons.
This
yields
datasets
that
can
constrain
quantitative
models
relating
stimulus
geometry
to
neural
responses.
In
previous
studies,
we
have
used
genetic
algorithms
to
show
how
objects
are
encoded
as
configurations
of
3D
surface
fragments
and
medial
axis
elements.
In
recent
work,
we
have
studied
large
scale
shape
coding
of
scenes
and
rooms
in
the
ventral
pathway.
In
both
object
and
scene
representation,
neural
coding
dimensions
reflect
the
geometry
of
the
natural
world
and
the
information
we
need
about
it.
Date:
Tues.,
Mar.
28,
2017
Location:
PAS
2464
Time:
3:30
pm
Speaker:
Gunnar
Blohm
(Queens
University)
Title:
Spiking
Networks
for
Decision
Making
and
Working
Memory
Decision making and working memory are central to cognition. Working memory is the transient retention and manipulation of information that can then be used to make a selection among choices, i.e. a decision. I propose a unifying framework of neural dynamics that could underlie different key features of decision making (such as the speed-accuracy trade-off) and working memory (such as capacity, distractibility and overload). We developed spiking neural models that capture decisions and working memory independently or within the same network as a function of a single (cognitive) control parameter, which we propose to be distal network disinhibition. The predicted neural mechanisms are helpful in understanding canonical computations underlying a variety of cognitive process beyond decisions and working memory.