Neurosciences Commons^™

Magneto-Vestibular Stimulation (Mvs): Effects On Behaviour And Resting State Networks, Brainscan , Western University, Brian Corneil, Stefan Everling, Joe Gati, Pieter Medendorp

Project Summaries

The MRI environment can stimulate the balance sensors within the inner ear. This is known as magnetovestibular stimulation (MVS), which occurs within the inner ear. It arises because of biophysical interactions between the fluids within our inner ear, the balance sensors and the magnetic field within an MRI machine.

This vestibular system usually deteriorates with aging and is commonly dysfunctional in disorders like Parkinson's and Alzheimer's and following concussions and strokes.

Growing New Dendritic Spines To Correct Cognitive Deficits Of Schizophrenia, Brainscan , Western University, Nagalingam Rajakumar, Brian Allman, Wataru Inoue

Project Summaries

In this project, we will attempt to re-grow functional dendritic spines in an animal model of schizophrenia for the first time. By re-growing dendritic spines, we intend to restore glutamatergic neurotransmission and improve cognition.

Role Of Microglia Signaling In Brain Circuit Development And Cognition, Brainscan, Western University, Vania Prado, Marco Prado, Wataru Inoue

Project Summaries

We have generated two mouse models in which we can control the Gq and Gisignalling in microglia during specific periods of brain development so we can explore the mechanisms behind abnormal microglial function.

Using our mouse models, we can stimulate these signalling pathways during the critical period of postnatal brain development to understand whether they impact adult cognition by influencing normal synaptic pruning. Mouse models of autism show issues with social memory, attention, sociability and hyperactivity. We will therefore assess those behaviors in our mouse models to determine if any autism-like behaviours are present.

Establishing A Translational Platform For Studying Sensory Processing In Neurodevelopmental Disorders, Brainscan , Western University, Susanne Schmid, Brian Allman, Ryan Stevenson, Janis Cardy

Project Summaries

The causes for ASD and DLD are many, complex and largely unknown. One specific cause already identified is mutation of a single gene essential for neuronal development. A useful transgenic rat model has been developed with this mutation that exhibits disabilities very reminiscient of children with ASD or DLD. We will use it to demonstrate that the same tests can show the same disruptions to the auditory system between children with ASD/DLD and this rat model. This model can then be used to undertake further exploration of the impact of ASD/DLD on the auditory system and evaluation of possible behavioural …

The Impact Of Violent Gaming On The Brain As A Function Of Individual Differences In Trait Empathy, Brainscan , Western University, Derek Mitchell, Elizabeth Finger, Richard Neufeld

Project Summaries

In this project, we will uncover any existing interaction between violent media and the capacity for empathic reactions (known as trait empathy) at a neural level, as the foundational milestone for the kind of large-scale study discussed above.

The level of trait empathy varies by individual - we will explore whether exposure to violent media exacerbates the difficulties that those with low trait empathy already show in relating to the emotions of others

Relating Functional And Structural Signatures Of Parkinson’S Disease To Changes In Dopamine Signalling: A Pet/Fmri Study, Brainscan . Western University, Penny Macdonald, Udunna Anazodo, Justin Hicks, Frank Prato, Alain Dagher

Project Summaries

Cognitive impairments in early Parkinson's disease are known to be linked to complex changes in the dopamine system within the brain. For example, dopamine-producing neurons in one key region of the brain are significantly degenerated, but those in another are spared. Dopamine-replacement therapy (DRT) has been pursued and it has produced significant improvements in certain cognitive functions - unfortunately it also produced significant impairments in others.

Protecting Against Hemodialysis Induced Neuro-Cognitive Injury, Brainscan , Western University, Chris Mcintyre, Adrian Owen 6612111

Project Summaries

Patients requiring dialysis for kidney failure have poorer survival rates than many kinds of cancer and they suffer very high rates of cardiovascular mortality. One of the near-universal symptoms of hemodialysis (HD), where a patient's blood is filtered externally with a dialysis machine, is cognitive impairment. We have already demonstrated that cooling the washing fluid in the dialysis machine, known as dialysate, can help maintain blood pressure during dialysis and protect against further brain injury.

The Role Of Astrocytes In Memory: Focus On Pattern Separation, Brainscan , Western University, Timothy Bussey, Vania Prado, Ceci Kramar, Marco Prado, Lisa Saksida

Project Summaries

It has recently been shown that astrocytes play a leading role in a particular aspect of memory known as 'pattern separation' - differentiating between similar experiences or episodes in memory (say, recalling where you parked your car today compared to where you parked it yesterday). Pattern separation is disrupted in a wide variety of diseases of the brain so it is of considerable interest to memory researchers.

We have already shown in a small pilot study that we can improve pattern separation with selective manipulation of astrocytes in a specific brain region. In this project, we will attempt to demonstrate …

Ommaba: The Open Multimodal Music And Auditory Brain Archive, Brainscan , Western University, Jessica Grahn, Jorn Diedrichsen, Joe Gati, Molly Henry, Robert Zatorre, Jean-Baptiste Poline, Bratislav Misic, Estrid Jakobsen, Mor Regev, Marcel Farrés Franch, Virginia Penhune, Emily Coffey

Project Summaries

We will create a specific neuroimaging database focused on the auditory domain. It will allow researchers to ask questions about the neural circuitry underlying auditory behaviour in the healthy brain and to understand the sources of individual variability. We will include detailed information about experiential factors, such as musicianship and bilingualism that are not documented in any existing databases, so that it will be possible to investigate plasticity-related effects. It will also provide baseline data for clinical studies.

Integrating Behavioural, Imaging And Transcriptional Profiling To Discover The Impact Of Midlife Stress In Alzheimer's Disease, Brainscan , Western University, Tim Bussey, Flavio Beraldo, Chakravarty Maller, Rosemary Bagot, Sylvain Williams, Claudia Kleinman

Project Summaries

We will be integrating this cognitive assessment with imaging of brain structure and function to understand the mechanisms by which a risk factor, in this case modifiable life stress, influences Alzheimer's disease-related decline. The resultant data will be integrated and disseminated using a new open-access neuroinformatics platform developed at Western (MouseBytes.ca), which will become a unique resource for open science investigations and set the standard for sharing of behavioural data across the world.

Pet And Mri Measurements Of Neuroinflammation And Brain Plasticity After A Stroke, Brainscan , Western University, Jonathan Thiessen, Shawn Whitehead, Justin Hicks, Matthew Fox

Project Summaries

We are going to assess brain structure and function using magnetic resonance imaging (MRI) and positron emission tomography (PET) to study white matter inflammation and the density of synapses over time, alongside a behavioural assessment of motor and executive function. This kind of comprehensive assessment, especially using PET to measure synaptic density, has not been done before.

Communicating With Patients With Disorders Of Consciousness By Translating Thoughts Into Light, Brainscan , Western University, Keith St. Lawrence, Adrian Owen, Derek Debicki, Teneille Gofton, Daniel Milej

Project Summaries

we intend to show, for the first time, that fNIRS can be used to reliably communicate with disorders of consciousness patients. There are many practical challenges to resolve (which are common to both fNIRS and EEG) such as involuntary movements by the patient, variability in consciousness itself, physical distortion in the head (such as from trauma) and a person's limited ability to perform repetitive mental tasks.

We will focus on patients who have already demonstrated by fMRI that they can perform motor imagery activation and plan to study up to 20 such patients over the course of a year.

Assessing Listening With Engaging, Real-World Auditory Signals, Brainscan , Western University, Björn Herrmann, Ingrid Johnsrude 6612111

Project Summaries

Our project will develop and evaluate a novel way (using functional imaging, fMRI, and electrophysiology, EEG) to assess this cognitive impact of hearing loss with engaging, real‐world auditory stimuli. We will try to assess listening effort in more realistic listening situations among healthy listeners, comparing detected effort in degraded and clear acoustic conditions.

Using EEG, we will then develop measures that are sensitive to the cognitive demands imposed by degraded speech, using these features to assess hearing function with engaging narratives in natural listening conditions.

Developing Behavioural Testing And Mr Imaging To Evaluate Cognitive Impairment In Models Of Cns Autoimmunity, Brainscan, Western University, Steven Kerfoot, Sarah Morrow, Ravi Menon, Flavio Beraldo

Project Summaries

This project will investigate cognition and cognitive fatigue in models of CNS autoimmunity. We will use automated touchscreens and fMRI to measure deficits in higher order brain functions.

We have two critical milestones in this project:

• to use touchscreen testing protocols to determine if mouse models demonstrate the same kinds of attention, working memory and cognitive fatigue deficits observed in MS, and
• to use fMRI to measure higher-order defects in the autoimmune models and identify any changes present that might be associated with cognitive dysfunction and the findings from human studies.

The Effect Of Musical Training On Speech And Sound Perception, Brainscan, Western University, Ingrid Johnsrude, Vanessa Irsik, Stephen Van Hedger

Project Summaries

We are going to carry out such a study, in conjunction with research labs at five other institutions. With six universities involved, we will be able to recruit a sufficiently large number of people in the study and decrease the likelihood of any regional bias influencing the outcomes. We will be trying to validate the following claims:

• that musicians have an improved ability to understand speech in noisy environments
• that the responses of a musician's brainstem to speech sounds is enhanced, and
• that older musicians have reduced symptoms from age-related hearing loss.

Developing Optogenetics/Electrophysiology Applications For Studying Cognitive Impairment During Stress, Brainscan, Western University, Wataru Inoue, Brian Allman, Julio Martinez-Trujillo

Project Summaries

We will develop cutting-edge techniques to:

• precisely measure and artificially manipulate the activity of CRH neurons in the PFC, and
• measure small and local releases of CRH by these neurons.

The success of our project will open the door to understand the neural mechanisms for how stress impairs cognitive functions and how it may contribute to mental disorders.

Attention Bias Modification Training As A Potential Preventative Tool, Brainscan, Western University, Elizabeth Hayden, Marc Joanisse, Pan Liu, Koraly Perez-Edgar, Thomas Olino

Project Summaries

We will use eye-tracking techniques to understand more about attentional bias and how it changes through ABM training.

Through neuroimaging, we will look at 'resting state functional connectivity', which is the activity and communication in the brain when a person is not engaging in any activity themselves. There are resting-state patterns of brain activity that have been identified in the brains of youth with depression, anxiety and related disorders, but we do not know if these brain patterns can be used to identify those at risk for these disorders. We also don't know if preventative approaches to depression and anxiety, …

Validating Methods For Using Noninvasive Brain Stimulation To Influence Auditory Perception, Brainscan, Western University, Jessica Grahn, Molly Henry, Blake Butler, Marc Joanisse, Stefan Everling

Project Summaries

We will be exploring the influence of a weak alternating current on neural activity at different frequencies to build a more complete picture of tACS. We will also incorporate EEG measurements to help us predict how the synchronization varies across individuals, to determine when to provide stimulation for each individual. Finally, we will vary the tACS stimulation and use participant behaviour as the measure to understand what stimulation timing produces the largest behavioural changes.

Uncovering The Neural Basis Of Cognitive Impairment Following Hearing Loss: An All-Optical Electrophysiology Approach, Brainscan, Western University, Brian Allman, Wataru Inoue

Project Summaries

We have access to state-of-the-art equipment that will enable us to visualize specific neuron types in animal models. This is a new approach that combines several recent advances in the field of 'optogenetics', a technique that uses light to control neurons. This approach will allow us to explore how hearing loss induced by loud noise exposure leads to abnormal neural activity in areas of the brain that control learning, memory and higher cognitive function.

The Effects Of Habits On Motor Skill Learning (Research Summary), Brainscan, Western University, Nicola J. Popp, Atsushi Yokoi, Paul Gribble, JöRn Diedrichsen

Research Summaries

Learning new motor skills can involve adopting motor habits that could help or hinder overall performance outcomes. Which habit(s) a participant adopt(s) can be induced early on through instruction. These motor habits can be rigid and persistent during motor skill training and practice but it is also possible to influence or change motor habits through training.

Persistent Post-Concussion Brain Changes In Adolescent Hockey Players, Brainscan, Western University, Kathryn Y. Manning, Amy Schranz, Robert Bartha, Gregory A. Dekaban, Christy Barreira, Arthur Brown, Lisa Fischer, Kevin Asem, Timothy J. Doherty, Douglas D. Fraser, Jeff Holmes, Ravi S. Menon

Research Summaries

Changes continue to occur in a concussed brain even after standard clinical tests have returned to normal. Damage in the very long fibre tracks in the brain of concussed players can be detected up to three months after the concussion and after the individuals have been approved for return to athletics. It is also possible to detect ‘hyper-connectivity’ in the brain, suggesting the brain is still trying to compensate for the concussion.

Familiar Voices Are More Intelligible, Even If They Are Not Recognized As Familiar, Brainscan, Western University, Emma Holmes, Ysabel Domingo, Ingrid Johnsrude

Research Summaries

This research has demonstrated that it’s easier to understand someone who is familiar to us (compared to someone unfamiliar) even if we can’t recognize them from their voice. As listeners, we focus on certain parts of speech sounds for specific purposes. For example, there may be some situations in which you can understand words spoken by your mother very well, better than you could understand a stranger in the same situation, even if you can’t tell that it’s your mother speaking.

Aging Is Associated With An Over-Sensitivity Of Brain Responses To Sounds, Brainscan, Western University, Björn Herrmann, Burkhard Maess, Ingrid S. Johnsrude

Research Summaries

Aging and hearing loss leads to increased neural responses to sounds in the auditory cortex compared to younger people. Enhanced neural activity to sound may be a physiological mechanism underlying the difficulty that older adults have with ignoring irrelevant sound information.

Preventing Noise-Induced Hearing Loss With A Novel Pharmaceutical, Brainscan, Western University, Brian Allman, Paul Walton, Shawn Whitehead, Patti Kiser, Brian Shilton, Sarah Hayes

Research Summaries

A targeted catalase, packaged and delivered via exosomes intranasally, provides protection for cochlear cells against oxidative stress, the kind of stress that results from loud noise exposure. It is able to cross the blood-brain barrier and does not result in negative outcomes elsewhere in the body.

Higher And Lower Order Factor Analyses Of The Temperament In Middle Childhood Questionnaire., Yuliya Kotelnikova, Thomas M Olino, Daniel N Klein, Sarah V M Mackrell, Elizabeth P Hayden

Brain and Mind Institute Researchers' Publications

The Temperament in Middle Childhood Questionnaire (TMCQ) is a widely used parent-report measure of temperament. However, neither its lower nor higher order structures has been tested via a bottom-up, empirically based approach. We conducted higher and lower order exploratory factor analyses (EFAs) of the TMCQ in a large ( N = 654) sample of 9-year-olds. Item-level EFAs identified 92 items as suitable (i.e., with loadings ≥.40) for constructing lower order factors, only half of which resembled a TMCQ scale posited by the measure's authors. Higher order EFAs of the lower order factors showed that a three-factor structure (Impulsivity/Negative Affectivity, Negative …

Hippocampal Gaba Enables Inhibitory Control Over Unwanted Thoughts, Taylor W. Schmitz, Marta M. Correia, Catarina S. Ferreira, Andrew P. Prescot, Michael C. Anderson

Brain and Mind Institute Researchers' Publications

© 2017 The Author(s). Intrusive memories, images, and hallucinations are hallmark symptoms of psychiatric disorders. Although often attributed to deficient inhibitory control by the prefrontal cortex, difficulty in controlling intrusive thoughts is also associated with hippocampal hyperactivity, arising from dysfunctional GABAergic interneurons. How hippocampal GABA contributes to stopping unwanted thoughts is unknown. Here we show that GABAergic inhibition of hippocampal retrieval activity forms a key link in a fronto-hippocampal inhibitory control pathway underlying thought suppression. Subjects viewed reminders of unwanted thoughts and tried to suppress retrieval while being scanned with functional magnetic resonance imaging. Suppression reduced hippocampal activity and memory …

Multiparametric Mri Changes Persist Beyond Recovery In Concussed Adolescent Hockey Players, Kathryn Y. Manning, Amy Schranz, Robert Bartha, Gregory A. Dekaban, Christy Barreira, Arthur Brown, Lisa Fischer, Kevin Asem, Timothy J. Doherty, Douglas D. Fraser, Jeff Holmes, Ravi S. Menon

BrainsCAN Publications

Objective: To determine whether multiparametric MRI data can provide insight into the acute and long-lasting neuronal sequelae after a concussion in adolescent athletes.

Methods: Players were recruited from Bantam hockey leagues in which body checking is first introduced (male, age 11–14 years). Clinical measures, diffusion metrics, resting-state network and region-to-region functional connectivity patterns, and magnetic resonance spectroscopy absolute metabolite concentrations were analyzed from an independent, age-matched control group of hockey players (n 5 26) and longitudinally in concussed athletes within 24 to 72 hours (n 5 17) and 3 months (n 5 14) after a diagnosed concussion.

Results: There were …

The Large-Scale Organization Of Shape Processing In The Ventral And Dorsal Pathways, Erez Freud, Jody C. Culham, David C. Plaut, Marlene Behrmann

Brain and Mind Institute Researchers' Publications

Although shape perception is considered a function of the ventral visual pathway, evidence suggests that the dorsal pathway also derives shape-based representations. In two psychophysics and neuroimaging experiments, we characterized the response properties, topographical organization and perceptual relevance of these representations. In both pathways, shape sensitivity increased from early visual cortex to extrastriate cortex but then decreased in anterior regions. Moreover, the lateral aspect of the ventral pathway and posterior regions of the dorsal pathway were sensitive to the availability of fundamental shape properties, even for unrecognizable images. This apparent representational similarity between the posterior-dorsal and lateral-ventral regions was corroborated …

Vocabulary Learning Benefits From Rem After Slow-Wave Sleep., Laura J Batterink, Carmen E Westerberg, Ken A Paller

Brain and Mind Institute Researchers' Publications

Memory reactivation during slow-wave sleep (SWS) influences the consolidation of recently acquired knowledge. This reactivation occurs spontaneously during sleep but can also be triggered by presenting learning-related cues, a technique known as targeted memory reactivation (TMR). Here we examined whether TMR can improve vocabulary learning. Participants learned the meanings of 60 novel words. Auditory cues for half the words were subsequently presented during SWS in an afternoon nap. Memory performance for cued versus uncued words did not differ at the group level but was systematically influenced by REM sleep duration. Participants who obtained relatively greater amounts of REM showed a …

Accumulation Of Non-Numerical Evidence During Nonsymbolic Number Processing In The Brain: An Fmri Study, Tali Leibovich, Daniel Ansari

Brain and Mind Institute Researchers' Publications

Behavioral evidence has shown that when performing a nonsymbolic number comparison task (e.g., deciding which of two dot arrays contains more dots), participants' responses are sensitive to affected by both numerical (e.g., number of items) and non-numerical magnitudes (i.e., area, density, etc.). Thus far it is unclear what brain circuits support this process of accumulating non-numerical variables during nonsymbolic number processing. To investigate this, 21 adult participants were asked to engage in a dot comparison task. To measure the neural correlates of accumulating numerical and non-numerical variables, we manipulated the number of the non-numerical magnitudes that were congruent (correlated with …