The
brain's major purpose is
to generate actions to interact with our environment. Sensory inputs
are the main sources of information used to guide these actions. In my
lab,
we are
interested in (1) how different sensory inputs are combined to generate
a unified representation of the world that can then be (2) interpreted
and transformed into action plans which (3) control our different motor
systems. All three stages of this process are highly dynamic and
represent complex computational steps.
Please find a list of equipment available in
my lab here.
Specifically, my lab asks the following questions:
How
and where does
the brain perform the complete 3D reference frame transformation of
hand and
target position for reaching?
This
research
line investigates how the brain performs the geometric transformation
between the incoming visual (and / or proprioceptive) information of
the hand and/or reach target and the motor command sent to direct
reaching arm movements. I'm interested in how position and velocity
signals are used and combined in the brain in a geometrically optimal
fashion to produce accurate behavior. Investigating this issue involves
modeling of the underlying geometry, a neural network approach to
address how this transformation could be performed by distributed
processing in the brain and functional brain imaging to uncover where
and when in the brain these processes take place.
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Where and how does
the brain use 3D position and velocity signals for saccade and smooth
pursuit control?
Smooth pursuit and
saccadic eye movements interact a great deal. Saccades can occur during
smooth pursuit and in addition the head can move during a pursuit
movement as it can during saccades. As a result we
have 3 control systems (saccade, pursuit and head) that have to be
coordinated in time in order to produce accurate and optimal combined
behaviour. The use of retinal and extraretinal 3D
position and velocity signals in this control problem are of special
interest to me. How can we generate geometrically accurate combined eye
and head movements? How is visual information transformed into motor
commands for the eyes and head. And how do higher-level processes (e.g.
attention) influence this eye-head coordination for saccades and
pursuit.
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How
are different sensory
sources used for perception and internal representation of 3D space?
We
live in a 3D environment. However, most research investigating
perception and action in 3D space ignores the distance dimension and
considers space merely as a 2D surface. Therefore, there are many
unsolved problems and questions concerning the use of 3D signals in
perception and the internal representation of 3D space for action. For
example, how can a 3D internal representation of space be constructed
from binocular vision in a distributed processing scheme? Are the same
3D eye and head position signals that are used for action also used for
perception? There are many open theoretical and experimental questions
to answer here.
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