Digital Commons Network^™

Investigating The Role Of Pannexin 3 In Intervertebral Disc Health And Disease, Meaghan E. Serjeant

Electronic Thesis and Dissertation Repository

Pannexin 3 (Panx3) is a mechanosensitive, channel-forming glycoprotein implicated in the progression of post-traumatic osteoarthritis. Despite evidence for Panx3 expression in intervertebral discs (IVDs), its function here remained unknown. Using Panx3^-/- mice, this study investigated the role of Panx3 in age-associated and injury-induced models of IVD degeneration. While loss of Panx3 did not significantly impact the progression of age-associated IVD degeneration, it was associated with a protective phenotype in an injury model of IVD degeneration, specifically in the annulus fibrosus (AF). Following IVD injury, WT mice showed an accumulation of enlarged cells that appeared to contribute to disrupted AF …

Longitudinal Alzheimer's Degeneration Reflects The Spatial Topography Of Cholinergic Basal Forebrain Projections, Taylor W. Schmitz, Marieke Mur, Meghmik Aghourian, Marc Andre Bedard, R. Nathan Spreng

Brain and Mind Institute Researchers' Publications

© 2018 The Author(s) The cholinergic neurons of the basal forebrain (BF) provide virtually all of the brain's cortical and amygdalar cholinergic input. They are particularly vulnerable to neuropathology in early Alzheimer's disease (AD) and may trigger the emergence of neuropathology in their cortico-amygdalar projection system through cholinergic denervation and trans-synaptic spreading of misfolded proteins. We examined whether longitudinal degeneration within the BF can explain longitudinal cortico-amygdalar degeneration in older human adults with abnormal cerebrospinal fluid biomarkers of AD neuropathology. We focused on two BF subregions, which are known to innervate cortico-amygdalar regions via two distinct macroscopic cholinergic projections. To …

Assessing Cognitive Function In Chronic Sport-Related Head Impacts And Aging, Danielle Brewer-Deluce

Electronic Thesis and Dissertation Repository

Healthy normal aging and cumulative head trauma (concussion and subconcussion), can influence cognition independently and concomitantly leading to substantial late-life cognitive impairments (e.g., as seen in increased rates of dementia). With this as motivation, this dissertation explores three aspects of aging, head injury and cognition using the Cambridge Brain Sciences (CBS) cognitive battery (www.cambridgebrainsciences.com).

Study 1 (Chapter 2): Concussion-specific testing combines assessments from multiple domains to evaluate a variety of functions. While clinically relevant, their succinct nature limits the amount of cognitive information available. Eighteen male football athletes were examined at baseline using the Sport Concussion Assessment Tool (SCAT) 3, …

Cognitive Changes Following Multiple-Modality Exercise And Mind-Motor Training In Older Adults With Subjective Cognitive Complaints: The M4 Study, Narlon Cassio Boa Sorte Silva, Dawn P. Gill, Adrian M. Owen, Teresa Liu-Ambrose, Vladimir Hachinski, Ryosuke Shigematsu, Robert Petrella

Lifestyle Research Team

Background

We investigated the effects of multiple-modality exercise with additional mind-motor training on cognition in community-dwelling older adults with subjective cognitive complaints.

Methods

Participants (n = 127, mean age 67.5 [7.3] years, 71% women) were randomized to receive 45 minutes of multiple-modality exercise with additional 15 minutes of either mind-motor training (M4, n = 63) or control (balance, range of motion and breathing exercises [M2, n = 64]). In total, both groups exercised 60 minutes/day, 3 days/week, for 24 weeks. Standardized global cognitive functioning (GCF), concentration, reasoning, planning, and memory were assessed at 24 weeks and after a 28-week no-contact …

Cognitive Changes Following Multiple-Modality Exercise And Mind-Motor Training In Older Adults With Subjective Cognitive Complaints: The M4 Study, Narlon Cassio Boa Sorte Silva, Dawn P. Gill, Adrian M. Owen, Teresa Liu-Ambrose, Vladimir Hachinski, Ryosuke Shigematsu, Robert Petrella

Lifestyle Research Team

Background

We investigated the effects of multiple-modality exercise with additional mind-motor training on cognition in community-dwelling older adults with subjective cognitive complaints.

Methods

Participants (n = 127, mean age 67.5 [7.3] years, 71% women) were randomized to receive 45 minutes of multiple-modality exercise with additional 15 minutes of either mind-motor training (M4, n = 63) or control (balance, range of motion and breathing exercises [M2, n = 64]). In total, both groups exercised 60 minutes/day, 3 days/week, for 24 weeks. Standardized global cognitive functioning (GCF), concentration, reasoning, planning, and memory were assessed at 24 weeks and after a 28-week no-contact …

The Impact Of Blood Pressure Dipping Status On Cognition, Mobility And Cardiovascular Health In Older Adults Following An Exercise Program, Narlon Cassio Boa Sorte Silva, Michael A. Greagory, Dawn P. Gill, Cheri L. Mcgowan, Robert Petrella

Lifestyle Research Team

Objectives: To determine whether a dual-task gait and aerobic exercise intervention differentially impacted older adults with normal blood pressure (BP) dipping status (dippers) compared to those with nondipping status (nondippers).

Methods: This study was a secondary analysis involving participants (mean age = 70.3 years, 61% women) who attended a laboratory-based exercise intervention over a 6-month period (40 min/day and 3 days/week). Participants were assessed in measures of cognition, mobility, and cardiovascular health at baseline, 3, 6, and 12 months (after a 6-month no-contact follow-up).

Results: We observed improvements in cognition in both groups at 6 and 12 months, although no …

Osteoarthritis, Cerebrovascular Dysfunction And The Common Denominator Of Inflammation: A Narrative Review, B. K. Al-Khazraji, C. T. Appleton, F. Beier, T. B. Birmingham, J. K. Shoemaker

Physiology and Pharmacology Publications

© 2018 The Author(s) Objective: Population-based cohort studies suggest an association between osteoarthritis (OA) and cerebrovascular disease, yet the mechanisms underlying vascular comorbidities in OA remain unclear. The purpose of this narrative review is to discuss the literature examining inflammation in OA with a focus on physiological mechanisms, and whether overlapping mechanisms exist in cerebrovascular dysfunction. Method: A literature search was conducted in PubMed using combinations of search terms: osteoarthritis, cerebrovascular (disease/dysfunction/risk), cardiovascular (disease/dysfunction/risk), aging/ageing, inflammation, inflammatory mediators, cytokine, c-reactive protein, interleukin, advanced glycation end-products, metabolic syndrome, reactive oxidative species, cognitive impairment, (vascular-related) dementia, small cerebral vessel disease, endothelial function, …

Aging Affects Adaptation To Sound-Level Statistics In Human Auditory Cortex, Björn Herrmann, Burkhard Maess, Ingrid S. Johnsrude

Brain and Mind Institute Researchers' Publications

Optimal perception requires efficient and adaptive neural processing of sensory input. Neurons in nonhuman mammals adapt to the statistical properties of acoustic feature distributions such that they become sensitive to sounds that are most likely to occur in the environment. However, whether human auditory responses adapt to stimulus statistical distributions and how aging affects adaptation to stimulus statistics is unknown. We used MEG to study how exposure to different distributions of sound levels affects adaptation in auditory cortex of younger (mean: 25 years; n=19) and older (mean: 64 years; n=20) adults (male and female). Participants passively listened to two sound-level …

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.

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.

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.

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.

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, …

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.

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.

Reading As A Lifeline Among Aging Readers, Paulette Rothbauer, Nicole Dalmer

FIMS Publications

No abstract provided.