BrainsCAN's Postdoctoral Associates

Through the Postdoctoral Fellowship Program, BrainsCAN is bringing the world’s most promising early career cognitive neuroscientists to Western University. Training the next generation of researchers is a key aim of BrainsCAN, and postdoctoral fellows are the engines of innovative research.

In fall 2017, the first set of fellows joined the program under the designation of a BrainsCAN Fellow or Postdoctoral Associate. 

Learn about the Postdoctoral Associates and their research.


Current BrainsCAN Postdoctoral Associates:
Justine Cléry, Felix Desmeules-Trudel, Chelsea Ekstrand, Chris Forgaard, Roy Haast, Ahmed HashadHiroyuki Igarashi, Jonathan MichaelsSasha Reschechtko, Melissa Troyer, Yiming Xiao

Former BrainsCAN Postdoctoral Associates: 
Cassandra Lowe, Christina McDonnell, Joana Vieira, Jeff Weiler

Current BrainsCAN Postdoctoral Associates

Justine Clery
Justine Cléry
BrainsCAN Postdoctoral Associate
PhD, Neurosciences and Cognition - Université Claude Bernard Lyon I, France

Identification of the effective connectivity changes in cortical and subcortical networks during pro- and antisaccades using combination of fMRI and optogenetics/electrical microstimulation in NHPs

Supervisor(s): Dr. Stefan Everling, Dr. Ravi Menon
Research Information:
Humans and NHPs have an exceptional ability to voluntarily control their actions. This control is crucial in a swiftly changing environment when automatic or previously learned responses can no longer achieve a goal, for example when subjects must inhibit a habitual response, ignore distracting stimuli, shift between tasks, or choose between competing alternative actions. To successfully switch from one task to another, task relevant information must be selected and maintained over task-irrelevant information. Functional neuroimaging studies have found a network of frontoparietal brain areas that activates more strongly on trials where the task is switched then repeated, including the dorsolateral prefrontal cortex, frontal eye fields (FEF), anterior cingulate cortex, and posterior parietal cortex and also supported by task selective activity from single unit recordings in NHPs. The main objective of the present research proposal is to identify effective connectivity changes in cortical and subcortical networks during pro- and anti-saccades using a combination of fMRI and optogenetic/electrical microstimulation in NHPs. In addition, we will examine how large-scale functional and effective connectivity changes while the NHPs learn the task.
Felix
Félix Desmeules-Trudel
BrainsCAN Postdoctoral Associate (top-up)
PhD, Linguistics - University of Ottawa

Second language learning: From low-level phonetic processing to learning new words

Supervisor(s): Dr. Marc Joanisse
Research Information:
Since a great number of speaker-listeners around the world use more than one language on a daily basis, knowledge and use of a second language are at the core of worldwide communication. It is therefore surprising that the brain mechanisms of second-language learning and use are still not well understood. Our research thus focuses on the neurocognitive bases of second-language acquisition, specifically sound processing, word learning, and the impact of sleep on memory consolidation of newly-learned linguistic information. Using simultaneous eye movement and electrophysiological measurements over multiple testing sessions separated by sleep, we hope to contribute significantly to the description of brain functioning and language as a cognitive system, especially for speech perception, word learning, and word recognition. We aim to identify how typical linguistic behaviour relates to underlying brain circuits in second-language learners, to contribute to curriculum development and intervention in second-language classrooms, and to help diagnosis and treatment of language disorders in multilinguals.
Chelsea Ekstrand
Chelsea Ekstrand
BrainsCAN Postdoctoral Associate
PhD, Psychology, Cognition and Neuroscience - University of Saskatchewan

Advancing inter-subject correlation approaches to naturalistic cognition using immersive virtual environments

Supervisor(s): Dr. Jody Culham, Dr. Ingrid Johnsrude
Research Information:
A central goal of neuroscience is to understand the complex neural dynamics of real-world experiences and how they are affected by brain disorders. Excitingly, recent functional magnetic resonance imaging (fMRI) research has identified highly consistent inter-subject correlations of neural activation when participants watch movies. To expand on this, we will develop immersive action videogames that will work with fMRI in order to monitor participants’ cognitive functions as they take part in these games. This will provide insight into the neural processing of real-world stimuli. We will evaluate the effectiveness of this stimuli as a clinical research tool using epilepsy and Parkinson’s disease as representative pathologies. The project will seek to examine systematic differences in ISCs to uncover potential diagnostic markers between pathological and healthy participants. This research may have significant impact on clinical diagnosis of brain disorders, opening the door for future research to develop models of normal and pathological brain function.
Chris Forgaard
Chris Forgaard
BrainsCAN Postdoctoral Associate
PhD, Human Motor Control - University of British Columbia

Neuroplasticity in sensorimotor feedback driven by visual observation

Supervisor(s): Dr. Paul Gribble, Dr. Andrew Pruszynski
Research Information:
An influential concept in neuroscience is that the acquisition of new movements can be mediated not only through physical practice, but also through the visual observation of a tutor learning a skill. Relevant investigations have focused on the influence of observational learning on voluntary movement control but whether observation can also influence reactive (feedback-based or “reflexive”) control remains to be explored. Our research program tests the hypothesis that visual observation of a tutor learning a motor skill produces similar changes in the observer’s feedback responses as physical practice, and that such changes reflect the formation of sensorimotor neural representations of the forces required for both movement and improvements in motor function. The findings of this research program are anticipated to have important clinical relevance. For example, previous work has produced conflicting findings on whether observation-based rehabilitation programs can improve sensorimotor function in various diseases such as stroke. It is also known that stroke survivors have a diminished capacity to adjust feedback responses in a goal-directed manner. A better understanding of how observational learning engages neural circuitry of both voluntary and feedback-based mechanisms in the healthy brain is necessary before we can test novel clinical interventions that have an observational component.
Roy Haast
Roy Haast
BrainsCAN Postdoctoral Associate
PhD, Neuroimaging - Maastricht University

Hippocampal subregion characterization using vascular ultra-high field MRI

Supervisor(s): Dr. Ali Khan, Dr. Stefan Köhler
Research Information:
The hippocampal formation is of vital importance for proper daily life functioning as it allows us to store and recall information. During this project, I will mainly focus on the anatomical and vascular differences across different parts of the hippocampal formation and how these relate to their functional specialization with respect to memory processing. The results of this project will (a) contribute to an enhanced understanding of the hippocampal formation, (b) facilitate the development of novel subregion-specific markers, and (c) fill current knowledge gaps to guide the interpretation of the observed structural and functional changes in neurodegenerative and vascular diseases.
Ahmed Hashad
Ahmed Hashad
BrainsCAN Postdoctoral Associate
PhD, Cardiovascular and Respiratory Sciences - University of Calgary

Cortical Microcircuits Underlying Stress-induced Cognitive Impairments

Supervisor(s): Dr. Wataru Inoue, Dr. Julio Martinez-Trujillo, Dr. Lisa Saksida, Dr. Tim Bussey
Research Information:
Stress impairs memory in healthy individuals and worsens it in mental illnesses. These impairments arise from defects in a specific brain region. We propose that a chemical signal that is produced during stress will suppress the activity of this brain region and impair memory. First, we will develop a state-of-the-art technique to sensitively measure this chemical signal in the brain during stress. Next, we will use an advanced memory testing system to examine the effects of this stress signal on specific types of memory. Interestingly, this protein is more abundant in females. So, we will test sex-specific effects of this protein.
Hiroyuki Igarashi
Hiroyuki Igarashi
BrainsCAN Postdoctoral Associate
PhD, Medical Sciences - Tohoku University, Japan

Optogenetic manipulation of intracellular calcium ion dynamics to regulate neural plasticity during stress

Supervisor(s): Dr. Wataru Inoue, Dr. Julio Martinez-Trujillo, Dr. Marco Prado
Research Information:
Stress impairs cognitive ability in otherwise healthy individuals and dramatically affects memory and learning in disparate brain disorders such as depression, anxiety disorders and autism. The effects of stress on cognition is due in part to the dysregulation of neural plasticity. This project will explain the spatiotemporal association of internal calcium ion – one of the second messengers – to neural plasticity and their roles in stress-induced cognitive impairment in mouse models.
Jonathan Michaels
Jonathan Michaels
BrainsCAN Postdoctoral Associate
PhD, Systems Neuroscience - University of Göttingen, Germany

Neural and Computational Basis of Goal-Dependent Feedback Control

Supervisor(s): Dr. Andrew Pruszynski, Dr. Jörn Diedrichsen
Research Information:
Think fast - a colleague unexpectedly bumps into your arm while you’re carrying your coffee mug. If the cup is full of hot coffee your reaction will look strikingly different than if the cup is empty. Understanding how the brain incorporates high-level contextual information while dealing with unexpected sensory feedback is essential in understanding movement. Yet, the brain regions and computational principles involved remain unclear. In this project we will generate a novel set of behavioural tasks, recording techniques, network models, and biomechanical modeling tools to elucidate the circuits and computations involved in using context and expectation to make feedback corrections in humans and NHP.
Sasha
Sasha Reschechtko
BrainsCAN Postdoctoral Associate
PhD, Kinesiology - Pennsylvania State University

Central determinants of recovery from peripheral nerve injury

Supervisor(s): Dr. Andrew Pruszynski, Dr. Jörn Diedrichsen
Research Information:
Peripheral nerve injury (PNI) in the upper limb often degrades hand function and quality of life. Peripheral nerves – including the median and ulnar nerves that innervate the hand – are capable of regrowth, but patients show a wide range of outcomes after regrowth is complete and many are left with markedly reduced hand function. Critically, the neural basis of successful recovery is unknown. Here, we propose a novel set of behavioral tasks and modern neuroimaging assays to directly test how cortical reorganization influences functional hand recovery after peripheral nerve injury in humans. Our work will provide new insights into the basic neural representation of the hand and may improve clinical practice by motivating interventions that target the precise neural determinants of successful recovery.
Melissa
Melissa Troyer
BrainsCAN Postdoctoral Associate
PhD, Cognitive Science - University of California, San Diego

Integrating big data and neuroimaging to understand variation in knowledge organization and its influence on language comprehension

Supervisor(s): Dr. Ken McRae, Dr. Marc Joanisse, Dr. Stefan Köhler
Research Information:
Language use heavily depends on speakers’ knowledge and expertise—imagine the difference between discussing an article from your field of study with a colleague vs. a social acquaintance. However, most models of language processing fail to incorporate the impact of such differences in knowledge. We will integrate behavioral studies, data mining tools, and neuroimaging methods to ask how expertise affects access to knowledge and its use in real time. We will first examine explicit knowledge, as a function of expertise, by conducting large-scale studies of free association within domains of interest, where people are asked to provide a list of concepts that are related to a prompt word’s meaning. We will compare these measures to those derived by applying state-of-the-art computational tools to large text corpora. We will then use neuroimaging (EEG/ERP) to explore the extent to which expertise influences the implicit availability of fine-grained semantic information, moment-by-moment, while people read and understand language. Given that dysfunctional access to knowledge is a hallmark of several major neurocognitive disorders, including dementia, schizophrenia, and aphasia, the proposed research may lead to a better understanding of how expertise might interact with or even mitigate potential deficits in this basic cognitive ability.
Yiming Xiao
Yiming Xiao
BrainsCAN Postdoctoral Associate
PhD, Biomedical Engineering - McGill University

Incorporating human brain connectome in planning deep brain stimulation to treat Parkinson's disease

Supervisor(s): Dr. Terry Peters, Dr. Ali Khan
Research Information:
As the second most frequent neuro-degenerative disorder worldwide, Parkinson's disease (PD) is primarily characterized by motor symptoms, but can also be accompanied by psychiatric symptoms, sleep disturbance, and cognitive impairment. Besides pharmaceutical therapy, deep brain stimulation (DBS) is an effective surgical treatment, where an electrode is implanted in the brain to re-normalize the motor neuro-circuitry. With the stimulation targets of the Globus Pallidus interna (GPi) and the subthalamic nucleus (STN), the success of the procedure depends on the accurate placement of the electrode while avoiding adjacent nuclei that can cause adverse effects. By integrating brain connectivity information, data-driven surgical planning can help improve the surgical planning of deep brain stimulation therapy to treat Parkinson’s disease.

 

Former BrainsCAN Postdoctoral Associates

Cassandra Lowe
Cassandra Lowe
BrainsCAN Postdoctoral Associate
PhD, Public Health and Health Systems - University of Waterloo
Christina McDonnell
Christina McDonnell
BrainsCAN Postdoctoral Associate
PhD, Clinical Psychology - University of Notre Dame
Joana Vieira
Joana Vieira
BrainsCAN Postdoctoral Associate (top-up)
PhD, Neuroscience - University of Porto, Portugal

 

Jeffery Weiler
Jeff Weiler
BrainsCAN Postdoctoral Associate (top-up)
PhD, Kinesiology - Western University