E-mail:
Research interests:
I am interested in how the
brain controls behavior. Many scientists approach this very large question by
starting with perception and asking how the brain builds an internal
representation of the world, and how it then uses this representation to guide
action. In contrast, I study behavior by starting with a concrete task such as
a voluntary movement and asking what parameters of the task the brain must
specify and control, and what information from the environment it may employ
toward that specification. The goal here is an understanding of brain
mechanisms for mediating interaction
with the world, not necessarily of mechanisms for representing the
world. A research program based on such an approach begins with questions
concerning motor control and gradually works its way toward the perceptual
systems which guide that control. One could say I'm going backwards through the
brain...
Please check out my Curriculum Vitae.
Lab News:
David’s paper on the basal
ganglia was recently published in Neuron
[PDF][suppl]. Congratulations
David!
Projects:
“Affordance competition hypothesis”
Classical theories in
psychology suggest that behavior consists of serial processes of computing representations of the world from
sensory information, using those representations to build knowledge and make
decisions, and then finally executing motor actions that implement those
decisions. However, these classic concepts are difficult to reconcile with the
growing body of neurophysiological data on decision processes distributed
throughout the sensorimotor system. Instead, we and others have proposed that the
basic functional architecture of behavior is parallel – and that the brain is continuously using sensory
information to specify potential actions available in the world (“affordances”)
while at the same time collecting cues for selecting which one is most
appropriate at a given moment. This very general hypothesis makes a number of
specific predictions, which we are testing through behavioral,
neurophysiological, and computational projects.
Pezzulo,
G. and Cisek, P. (2016) “Navigating the affordance landscape: Feedback control
as a process model of behavior and cognition”. Trends in Cognitive Sciences.
20(6): 414-424. [PDF]
Cisek, P.
and Kalaska, J.F. (2010) “Neural mechanisms for interacting with a world
full of action choices”. Annual Review of
Neuroscience. 33: 269-298. [PDF]
Cisek, P.
(2007) “Cortical mechanisms of action selection: The affordance competition
hypothesis” Philosophical Transactions of
the Royal Society B. 362: 1585-1599. [PDF]
[suppl]
Cisek, P.
(2006) “Integrated neural processes for defining potential actions and deciding
between them: A computational model”. Journal
of Neuroscience. 26(38): 9761-9770. [PDF] [suppl]
Cisek, P.
(1999) “Beyond the computer metaphor: Behaviour as
interaction”. Journal of Consciousness
Studies. 6(11-12): 125-142. [PDF]
“Biased competition in sensorimotor maps”
The affordance competition
hypothesis suggests that the brain can represent multiple potential actions in
parallel within the same regions involved in executing those actions during overt
behavior, and these parallel representations compete against each other during
decision-making. This competition is influenced by a variety of biases, such as
reward value and effort, and unfolds within a “sensorimotor map” that reflects
the geometry of the immediate environment. Our work with former student 
Alexandre Pastor-Bernier confirmed
two key predictions: 1) that reward values influence activity in premotor
cortex, but only when there is a choice to be made; and 2) that the competition
between two very different actions is stronger than a competition between
similar actions. In our newest project, led by doctoral student Ayuno
Nakahashi, we are testing whether decisions are made by a “central executive”
or through a “distributed consensus” across the cortical network. This involves
simultaneous neural recordings in the premotor and parietal cortex, using two
semi-chronically implanted microdrives each with 32
independently moveable electrodes.
Cisek, P.
(2012) “Making decisions through a distributed consensus”. Current Opinion in Neurobiology. 22(6): 927-936. [PDF]
Pastor-Bernier,
A., Tremblay, E., and Cisek, P. (2012) “Dorsal premotor cortex is involved in
switching motor plans”. Frontiers in Neuroengineering. 5(5). doi:
10.3389/fneng.2012.00005. [PDF]
Pastor-Bernier,
A. and Cisek, P. (2011) “Neural correlates of biased competition in premotor
cortex”. Journal of Neuroscience.
31(19): 7083-7088. [PDF] [suppl]
Cisek, P.
& Kalaska, J.F. (2005) “Neural correlates of reaching decisions in dorsal premotor
cortex: specification of multiple direction choices and final selection of
action”. Neuron. 45(5): 801-814. [PDF]
“The biomechanics of choices”
When playing a sport, we are faced
with a myriad of decisions between different possible actions, and the best
choice depends not only on potential outcomes but also on the effort associated
with each action. This project tests how human subjects take the biomechanical
costs of making different movements into account when selecting between
actions. It uses behavioral methods, transcranial magnetic stimulation (TMS) to
probe the evolving decision in the human motor cortex, and (in collaboration
with Andrea Green) galvanic vestibular stimulation to test the influence of
one’s body motion on their action choices.
Cos,
Cos,
Cos,
“Urgency-gating model”
To deal with a constantly changing
world, the brain must quickly process sensory information and make a variety of
trade-offs between the speed of a decision and its accuracy. Within the context
of affordance competition, we hypothesize that the process of deliberating
between different action options takes places through a competition occurring
within the sensorimotor system (premotor and primary motor cortex), combining
three sources of information: Spatial information about potential actions (from
visual and parietal cortex); evidence in favor of one action versus another
(from prefrontal cortex); and a growing signal related to the urge to make a
movement (from the basal ganglia). When the competition within these
sensorimotor regions is resolved, the brain commits to a choice and releases
the selected movement. We have been testing predictions of this hypothesis
through behavioral studies with humans, as well as neural recordings in
premotor, motor and prefrontal cortex as well as the basal ganglia.
Thura, D.
and Cisek, P. (2017) “The basal ganglia do not select reach targets but control
the urgency of commitment”. Neuron.
95(5): 1160-1170. [PDF][suppl]
Carland
M., Marcos, E., Thura, D., and Cisek, P. (2016) “Evidence against perfect integration
of sensory information during perceptual decision-making” Journal of Neurophysiology. 115(2): 915-930. [PDF]
Thura, D.
and Cisek, P. (2014) “Deliberation and commitment in the premotor and primary
motor cortex during dynamic decision-making” Neuron. 81(6): 1401-1416. [PDF][suppl]
Thura,
D., Beauregard-Racine, J., Fradet, C-W., and Cisek,
P. (2012) “Decision-making by urgency-gating: Theory and experimental support” Journal of Neurophysiology. 108(11):
2912-30. [PDF]
Cisek,
P., Puskas, G.A., and El-Murr,
S. (2009) “Decisions in changing conditions: The urgency-gating model”. Journal of Neuroscience. 29(37):
11560-11571. [PDF]
Current Lab Personnel:
Marie-Claude Labonté: Laboratory technician 2006-
David Thura: Postdoctoral
fellow 2008-
David
has been leading the behavioral and neural projects testing and refining the
urgency-gating model
Matthew Carland: Doctoral
student 2013-
Matthew’s
doctoral project studies the relationship between urgency (as quantified in our
simple decision tasks) and the psychological trait of impulsivity in humans.
Ayuno Nakahashi: Doctoral
student 2015-
Ayuno
is leading our new simultaneous neural recordings in premotor and parietal
cortex, testing for the existence or absence of a central executive in the
primate brain.
Julien Michalski: Master’s
student 2016-
Julien
is pioneering a new line of research in our lab, investigating how we make
decisions about actions while we’re already
acting, as during natural behavior.
Tim Meehan: Postdoctoral
fellow 2016-
Tim
is examining neural activity during decision-making from intracranial EEG
electrodes in human subjects awaiting epilepsy surgery.
Simon Haché: Master’s
student 2017- (co-supervised with Andrea Green)
Simon
is investigating how we select movements around obstacles and how those choices
are influenced by our own self motion.
Thomas Lusignan:
Undergraduate research intern 2018
Thomas
is performing analyses of local field potentials from the premotor and parietal
cortex of monkeys as they resolve decision conflicts.
Alumni:
Alexandre
Pastor-Bernier: PhD student 2007-2012, now postdoctoral fellow at
Thomas
Michelet: Postdoctoral fellow 2006-2008, now an assistant professor at the
Université de Bordeaux 2
Jean-Philippe Thivierge: Postdoctoral fellow 2006-2007, now an
associate professor at the University of Ottawa
Valeriya Gritsenko:
Research scientist 2008-2010, now assistant professor at the
Ignasi Cos: Postdoctoral fellow
2008-2012, now research scientist at the Universitat Pompeu Fabra, Barcelona
Geneviève Aude Puskas: Undergraduate research intern 2006
Stephany El-Murr: Undergraduate research intern 2007
Nicolas Bélanger: Undergraduate research intern 2009
Julie Beauregard-Racine: Undergraduate research intern 2009
Farid Medleg: Undergraduate research intern 2010
Charles-William Fradet: Undergraduate research intern 2010
Elsa Tremblay: Undergraduate research intern 2011
Jessica Trung: Undergraduate research intern 2013
Jean-François Cabana: Undergraduate research intern 2014
Albert Feghaly: Undergraduate research intern 2015
Guido Guberman: Visiting undergraduate intern 2015
Philippe Canstonguay: Undergraduate research intern 2016
Pierre-Éric Cazeau: Undergraduate research intern 2017
This page is permanently
under construction. Last update was on December 30,
2017.