My brain.MePaul Cisek Ph.D.

Department of Neuroscience
University of Montréal
2960 chemin de la tour, room 4117
Montréal (Québec) H3T 1J4 Canada
Phone: 514-343-6111 x4355
FAX: 514-343-2111
E-mail:
email

 

 


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:

Former postdoc David Thura has started his new job in Lyon and is already publishing! Here the link to his lab. I am so proud of him!!


Projects:

“Phylogenetic refinement”

In 1973, Dobzhansky famously said that “Nothing in biology makes sense except in the light of evolution”. I agree. For that reason, I’ve recently started devoting part of my time to reading about the evolutionary history of the nervous system, and writing a book about all the things I’ve learned. I’m doing this chronologically – that is, I read about early multicellular animals first, then about early chordates, vertebrates, etc. gradually working my way along the lineage that leads to humans. I believe this has given me a broader perspective on the brain and behavior, and on everything I do in the lab, because it has exposed me to some amazing work by people we don’t normally hear about in systems neuroscience circles. The book will take a long time to finish, but I summarized some of the key points in a paper published in 2019. That paper makes a very provocative proposal: that we should abandon many of the familiar concepts inherited from the history of psychology and instead resynthesize our conceptual taxonomy according to the history of evolution. A second paper, with some colleagues, applies this approach to theories of attention.

Cisek, P. (2019) “Resynthesizing behavior through phylogenetic refinement” Attention, Perception, and Psychophysics. 81(7): 2265-2287. [PDF]

Hommel, B., Chapman, C., Cisek, P., Neyedli, H., Song, J-H., and Welsh, T. (2019) “No one knows what attention is” Attention, Perception, and Psychophysics. 81(7): 2288-2303. [PDF]

 

“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 Screen Shot 2014-08-13 at 3Alexandre 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]

 

“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. (2020) “Microstimulation of dorsal premotor and primary motor cortex delays the volitional commitment to an action choice” Journal of Neurophysiology. 123(3): 927-935.

Carland, M., Thura, D., and Cisek, P. (2019) “The urge to decide and act: Implications for brain function and dysfunction” The Neuroscientist. 25(5): 491-511. [PDF]

Thura, D., Guberman, G., and Cisek, P. (2017) “Trial-to-trial adjustments of speed-accuracy trade-offs in premotor and primary motor cortex” Journal of Neurophysiology. 117(2): 665-683. [PDF]

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]

“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. Most recently, we’ve started looking at how decisions are made during ongoing actions, and found that this challenges some of our assumptions…

Cos, I., Duqué, J. and Cisek, P. (2014) “Rapid prediction of biomechanical costs during action decisions” Journal of Neurophysiology. 112(6): 1256-1266. [PDF]

Cos, I., Medleg, F., and Cisek, P. (2012) “The modulatory influence of endpoint controllability on decisions between actions” Journal of Neurophysiology. 108(6): 1764-80. [PDF]

Cos, I., Bélanger, N., and Cisek, P. (2011) “The influence of predicted arm biomechanics on decision-making”. Journal of Neurophysiology. 105(6): 3022-3033. [PDF]

Michalski, J., Green, A.M., Cisek, P. (2020) “Reaching decisions during ongoing actions” Journal of Neurophysiology. 123(3): 1090-1102.

 


 

Current Lab Personnel:

Marie-Claude Labonté: Laboratory technician 2006-

Matthew Carland: Doctoral student 2013-

Matthew’s doctoral project studies the relationship between urgency (as quantified in our simple decision tasks) and psychological traits 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 2016-2020 (Co-supervisor: Andrea Green)

Julien pioneered a new line of research in our lab, investigating how we make decisions about actions while we’re already acting, as during natural behavior. He is finishing his thesis while already working in industry.

Simon Haché: Master’s student 2017- (Primary supervisor: Andrea Green)

Simon is investigating how we select movements around obstacles and how those choices are influenced by our own self motion.

Thomas Lusignan: Master’s student 2018-

Thomas is performing analyses of local field potentials from the premotor and parietal cortex of monkeys as they resolve decision conflicts.

Tyler Peel: Postdoctoral fellow 2018-

Tyler is following up on our studies of the urgency-gating model, with simultaneous multielectrode recording in the prefrontal, premotor, and motor cortex, as well as the basal ganglia – even while monkeys are still learning the task.

Cesar Canaveral: Doctoral student 2019- (Co-supervisor: Andrea Green)

Cesar is following up on our studies of decisions during actions, introducing new task paradigms and additional approaches such as mechanical perturbations (using the KINARM) and transcranial magnetic stimulation.

Alumni:

Alexandre Pastor-Bernier: PhD student 2007-2012, now postdoctoral fellow at Cambridge University with Wolfram Schultz

Thomas Michelet: Postdoctoral fellow 2006-2008, now Team Leader 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 associate professor at the University of West Virginia

Ignasi Cos: Postdoctoral fellow 2008-2012, now assistant professor at the University of Barcelona

David Thura: Postdoctoral fellow 2008-2018, now Group Leader at the Lyon Neuroscience Research Center

Tim Meehan: Postdoctoral fellow 2016-2018, now data scientist in New York City

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

Thomas Lusignan: Undergraduate research intern 2018

Sandra Ferland: Undergraduate research intern 2019


This page is permanently under construction. Last update was on June 18, 2020.