Medicine and Health Sciences Commons^™

Multiple Mechanisms Of Consciousness: The Neural Correlates Of Emotional Awareness., Jayna M Amting, Steven G Greening, Derek G V Mitchell

Brain and Mind Institute Researchers' Publications

Emotional stimuli, including facial expressions, are thought to gain rapid and privileged access to processing resources in the brain. Despite this access, we are conscious of only a fraction of the myriad of emotion-related cues we face everyday. It remains unclear, therefore, what the relationship is between activity in neural regions associated with emotional representation and the phenomenological experience of emotional awareness. We used functional magnetic resonance imaging and binocular rivalry to delineate the neural correlates of awareness of conflicting emotional expressions in humans. Behaviorally, fearful faces were significantly more likely to be perceived than disgusted or neutral faces. Functionally, …

Optimal Slice Thickness For Cone-Beam Ct With On-Board Imager., Kyt Seet, A Barghi, Slav Yartsev, Jacob Van Dyk

Oncology Publications

PURPOSE: To find the optimal slice thickness (Δτ) setting for patient registration with kilovoltage cone-beam CT (kVCBCT) on the Varian On Board Imager (OBI) system by investigating the relationship of slice thickness to automatic registration accuracy and contrast-to-noise ratio.

MATERIALS AND METHOD: Automatic registration was performed on kVCBCT studies of the head and pelvis of a RANDO anthropomorphic phantom. Images were reconstructed with 1.0 ≤ Δτ (mm) ≤ 5.0 at 1.0 mm increments. The phantoms were offset by a known amount, and the suggested shifts were compared to the known shifts by calculating the residual error. A uniform cylindrical phantom …

Chronic Obstructive Pulmonary Disease: Longitudinal Hyperpolarized (3)He Mr Imaging, Miranda Kirby, Lindsay Mathew, Andrew Wheatley, Giles E Santyr, David G Mccormack, Grace Parraga

Medical Biophysics Publications

PURPOSE: To quantitatively evaluate a small pilot group of ex-smokers with chronic obstructive pulmonary disease (COPD) and healthy volunteers during approximately 2 years by using hyperpolarized helium 3 ((3)He) magnetic resonance (MR) imaging.

MATERIALS AND METHODS: All subjects provided written informed consent to the study protocol, which was approved by the local research ethics board and Health Canada and was compliant with the Personal Information Protection and Electronic Documents Act and HIPAA. Hyperpolarized (3)He MR imaging, hydrogen 1 MR imaging, spirometry, and plethysmography were performed in 15 ex-smokers with COPD and five healthy volunteers (with the same mean age and …

Deficits In Attention To Emotional Stimuli Distinguish Youth With Severe Mood Dysregulation From Youth With Bipolar Disorder., Brendan A Rich, Melissa A Brotman, Daniel P Dickstein, Derek G V Mitchell, R James R Blair, Ellen Leibenluft

Brain and Mind Institute Researchers' Publications

Studying attention in the context of emotional stimuli may aid in differentiating pediatric bipolar disorder (BD) from severe mood dysregulation (SMD). SMD is characterized by chronic irritability, arousal, and hyper-reactivity; SMD youth frequently receive a BD diagnosis although they do not meet DSM-IV criteria for BD because they lack manic episodes. We compared 57 BD (14.4 +/- 2.9 years old, 56% male), 41 SMD (12.6 +/- 2.6 years old, 66% male), and 33 control subjects (13.7 +/- 2.5 years old, 52% male) using the Emotional Interrupt task, which examines how attention is impacted by positive, negative, or neutral distracters. We …

Gender, Germs, And Dirt: A Case Study Of Properly Politicised Science, Sharyn Clough

XIV IAPh Symposium 2010

This presentation is part of the Feminist Perspectives in the Sciences: Epidemiology track.

The relatively recent increase in cases of allergies and asthma, especially in industrialised nations of the north and west, has been explained by the “hygiene hypothesis”—viz., that increased cleanliness and sanitation have unintended negative consequences for immune health—an hypothesis that has received robust epidemiological support (e.g., Platts-Mills 2002). Over the last few years, support for the hypothesis has increased with the discovery that populations regularly exposed to certain parasitic worms (helminths) have very low incidence of chronic inflammatory diseases such as Crohn’s (Elliot, Summers, and Weinstock 2007). …

If You Build It, They Still May Not Come: Outcomes And Process Of Implementing A Community-Based Integrated Knowledge Translation Mapping Innovation, S. Michelle Driedger, Anita Kothari, Ian D. Graham, Elizabeth Cooper, Eric J. Crighton, Melanie Zahab, Jason Morrison, Michael Sawada

Health Studies Publications

Background: Maps and mapping tools through geographic information systems (GIS) are highly valuable for turning data into useful information that can help inform decision-making and knowledge translation (KT) activities. However, there are several challenges involved in incorporating GIS applications into the decision-making process. We highlight the challenges and opportunities encountered in implementing a mapping innovation as a KT strategy within the non-profit (public) health sector, reflecting on the processes and outcomes related to our KT innovations.

Methods: A case study design, whereby the case is defined as the data analyst and manager dyad (a two person team) in selected Ontario …

Management Of Devastating Ocular Trauma--Experience Of Maxillofacial Surgeons Deployed To A Forward Field Hospital, M. J. Ansell, J. Breeze, Vivian C. Mcalister, M. D. Williams

Surgery Publications

Combat-related eye injuries continue to increase in frequency and are generally secondary to Improvised Explosive Devices. Many ocular injuries are potentially preventable by the wearing of ballistic eye protection. The management of penetrating eye trauma is normally outside the routine practice of maxillofacial surgeons in the UK. The aim of this paper is to describe the surgical techniques used in the modern management of devastating ocular trauma including selected case examples managed by British military maxillofacial surgeons deployed to Afghanistan.

Serum Lipids And Suicidality In Early Psychosis: Is There A Connection? A Preliminary Study, Amresh Srivastava, Megan Johnston, Lenore Purde, Robbie Campbell

Psychiatry Presentations

No abstract provided.

Psychoendocrinology (Thyroid Hormone) And Early Psychosis: Preliminary Findings, Amresh Srivastava, Megan Johnston, Lenore Purde, Robbie Campbell

Psychiatry Presentations

No abstract provided.

Linking Brain-Wide Multivoxel Activation Patterns To Behaviour: Examples From Language And Math, Rajeev D.S. Raizada, Feng Ming Tsao, Huei Mei Liu, Ian D. Holloway, Daniel Ansari, Patricia K. Kuhl

Paediatrics Publications

A key goal of cognitive neuroscience is to find simple and direct connections between brain and behaviour. However, fMRI analysis typically involves choices between many possible options, with each choice potentially biasing any brain-behaviour correlations that emerge. Standard methods of fMRI analysis assess each voxel individually, but then face the problem of selection bias when combining those voxels into a region-of-interest, or ROI. Multivariate pattern-based fMRI analysis methods use classifiers to analyse multiple voxels together, but can also introduce selection bias via data-reduction steps as feature selection of voxels, pre-selecting activated regions, or principal components analysis. We show here that …

In-Theater Peritoneal Dialysis For Combat-Related Renal Failure, Joseph S. Pina, Soraya Moghadam, Howard M. Cushner, Greg J. Beilman, Vivian C. Mcalister

Surgery Publications

BACKGROUND: Complications of renal failure may prevent timely evacuation of injured soldiers. Conventional renal replacement therapy is not available in forward surgical units. METHODS: Records of in-theater improvised peritoneal dialysis (IPD) in level III hospitals or forward surgical units in Iraq or Afghanistan were reviewed to determine the following: cause of renal failure and associated injuries; type of dialysate, peritoneal access, and exchange technique; and patient outcome. These data were used to propose method for IPD using commonly available materials. RESULTS: IPD is described in four patients. Abdominal or chest drains were used with either improvised dextrose-electrolyte solution or commercial …

To Be Or Not To Be': Education For Clinical Practice In Risk Assessment Of Suicide Behavior, Amresh Srivastava, Megan Johnstom

Data and Test Instruments

Clinical practice of psychiatry has acquired role and responsibility which goes far beyond traditional expectations .Incident of suicide, particularly, is considered a high liability for then professionals, organizations and the consumer. It also remains a clinical issue which examines can we prevent suicide which in the system of care. Studies have shown about 1 in 6 psychologists or psychiatrist are likely to loose a patient due to suicide in a mean duration of 18-20 years practice. Repeatedly it has demonstrated that clinical skill training for risk assessment is the necessary for all professionals not only in mental health but also …

To Be Or Not To Be: Education For Clinical Decisions In Risk Assessment Of Suicide Behavior, Amresh Srivastava, Megan Johnston

Data and Test Instruments

Clinical practice of psychiatry has acquired role and responsibility which goes far beyond traditional expectations .Incident of suicide, particularly, is considered a high liability for then professionals, organizations and the consumer. It also remains a clinical issue which examines can we prevent suicide which in the system of care. Studies have shown about 1 in 6 psychologist or psychiatrist are likely to loose a patient due to suicide in a mean duration of 18-20 years practice. Repeatedly it has demonstrated that clinical skill training for risk assessment is the necessary for all professionals not only in mental health but also …

In–Theater Peritoneal Dialysis For Combat-Related Renal Failure, Joseph Pina, Soraya Moghadam, Howard Cushner, Greg Beilman, Vivian Mcalister

Data and Test Instruments

BACKGROUND: Complications of renal failure may prevent timely evacuation of injured soldiers. Conventional renal replacement therapy is not available in forward surgical units. METHODS: Records of in-theater improvised peritoneal dialysis (IPD) in level III hospitals or forward surgical units in Iraq or Afghanistan were reviewed to determine the following: cause of renal failure and associated injuries; type of dialysate, peritoneal access, and exchange technique; and patient outcome. These data were used to propose method for IPD using commonly available materials. RESULTS: IPD is described in four patients. Abdominal or chest drains were used with either improvised dextrose-electrolyte solution or commercial …

Should 'Risk Syndrome Of Psychosis' Be Included In Dsm V As A Diagnosis? A Road Towards Preventive Psychiatry, Amresh Srivastava

Psychiatry Presentations

No abstract provided.

Enhancing Risk Assessment Across Mental Health Services, Amresh Srivastava, Megan Johnston, Charles Nelson

Psychiatry Presentations

No abstract provided.

Dysautonomia Due To Reduced Cholinergic Neurotransmission Causes Cardiac Remodeling And Heart Failure, Aline Lara, Denis D. Damasceno, Rita Pires, Robert Gros, Eneas R. Gomes, Mariana Gavioli, Ricardo F. Lima, Diogo Guimaraes, Patricia Lima, Carlos Roberto Bueno Jr., Anilton Vasconcelos, Danilo Roman-Campos, Cristiane A. S. Menezes, Raquel A. Sirvente, Vera M. Salemi, Charles Mady, Marc G. Caron, Anderson J. Ferreira, Patricia C. Brum, Rodrigo R. Resende, Jader S. Cruz, Marcus Vinicius Gomez, Vania F. Prado, Alvair P. De Almeida, Marco A. M. Prado, Silvia Guatimosim

Anatomy and Cell Biology Publications

Overwhelming evidence supports the importance of the sympathetic nervous system in heart failure. In contrast, much less is known about the role of failing cholinergic neurotransmission in cardiac disease. By using a unique genetically modified mouse line with reduced expression of the vesicular acetylcholine transporter (VAChT) and consequently decreased release of acetylcholine, we investigated the consequences of altered cholinergic tone for cardiac function. M-mode echocardiography, hemodynamic experiments, analysis of isolated perfused hearts, and measurements of cardiomyocyte contraction indicated that VAChT mutant mice have decreased left ventricle function associated with altered calcium handling. Gene expression was analyzed by quantitative reverse transcriptase …

Motor Output Evoked By Subsaccadic Stimulation Of Primate Frontal Eye Fields., Brian D Corneil, James K Elsley, Benjamin Nagy, Sharon L Cushing

Brain and Mind Institute Researchers' Publications

In addition to its role in shifting the line of sight, the oculomotor system is also involved in the covert orienting of visuospatial attention. Causal evidence supporting this premotor theory of attention, or oculomotor readiness hypothesis, comes from the effect of subsaccadic threshold stimulation of the oculomotor system on behavior and neural activity in the absence of evoked saccades, which parallels the effects of covert attention. Here, by recording neck-muscle activity from monkeys and systematically titrating the level of stimulation current delivered to the frontal eye fields (FEF), we show that such subsaccadic stimulation is not divorced from immediate motor …

Neuropilin 1 Directly Interacts With Fer Kinase To Mediate Semaphorin3a-Induced Death Of Cortical Neurons, Susan X. Jiang, Shawn N. Whitehead, Amy Aylsworth, Bogdan Zurakowski, Kenneth Chan, Jianjun Li, Sheng T. Hou

Anatomy and Cell Biology Publications

Neuropilins (NRPs) are receptors for the major chemorepulsive axonal guidance cue semaphorins (Sema). The interaction of Sema3A/NRP1 during development leads to the collapse of growth cones. Here we show that Sema3A also induces death of cultured cortical neurons through NRP1. A specific NRP1 inhibitory peptide ameliorated Sema3A-evoked cortical axonal retraction and neuronal death. Moreover, Sema3A was also involved in cerebral ischemia-induced neuronal death. Expression levels of Sema3A and NRP1, but not NRP2, were significantly increased early during brain reperfusion following transient focal cerebral ischemia. NRP1 inhibitory peptide delivered to the ischemic brain was potently neuroprotective and prevented the loss of …

Researchers’ Views On Ethical Challenges In Healthcare Cluster-Randomized Trials, Andrew Mcrae

Research Day (Arts & Humanities, FIMS, and Education)

• Cluster-randomized trials (CRTs) commonly used in education, public health, healthcare and social sciences
• Groups of individuals randomly assigned to receive one of 2 (or more) comparator interventions
• Effect of interventions evaluated after collecting data from individual group members
• Ethics guidelines developed for oversight of research enrolling individual subjects
• Little specific guidance for ethical conduct of CRTs
• Lack of guidance may lead to variability in ethics reviews between jurisdictions and over time

Never The Twain Shall Meet? Interspecialty Bioethics Education And Practice In Relation To Informed Consent For Surgery-Related Anesthesia, Kyoko Wada, Abraham Rudnick

Research Day (Arts & Humanities, FIMS, and Education)

The objectives of this research project are:

• Identify and analyze ethical problems concerning known practices regarding informed consent for surgery-related anesthesia
• Propose solutions to these problems, with a focus on interspecialty bioethics education

Conceptual Problems In Research Ethics, Charles Weijer

Research Day (Arts & Humanities, FIMS, and Education)

This poster addresses these issues:
• What good is medical research?
• What is owed to the study subject?
• When is research risk acceptable?
• How should we conduct research in developing countries?
• How should we conduct research involving communities?

Theta-Activity In Anterior Cingulate Cortex Predicts Task Rules And Their Adjustments Following Errors, Thilo Womelsdorf, Kevin Johnston, Martin Vinck, Stefan Everling

Brain and Mind Institute Researchers' Publications

Accomplishing even simple tasks depend on neuronal circuits to configure how incoming sensory stimuli map onto responses. Controlling these stimulus-response (SR) mapping rules relies on a cognitive control network comprising the anterior cingulate cortex (ACC). Single neurons within the ACC convey information about currently relevant SR mapping rules and signal unexpected action outcomes, which can be used to optimize behavioral choices. However, its functional significance and the mechanistic means of interaction with other nodes of the cognitive control network remain elusive and poorly understood. Here, we report that core aspects of cognitive control are encoded by rhythmic theta-band activity within …

The Prevalence And Causes Of Vision Loss In Indigenous Australians: The National Indigenous Eye Health Survey, Hugh R. Taylor, Jing Xie, Sarah Fox, Ross A. Dunn, Anna-Lena Arnold, Jill E. Keeffe

Aboriginal Policy Research Consortium International (APRCi)

Aim: To determine the prevalence and causes of vision loss in Indigenous Australians. Design, setting and participants: A national, stratified, random cluster sample was drawn from 30 communities across Australia that each included about 300 Indigenous people of all ages. A sample of non-Indigenous adults aged 􏱄 40 years was also tested at several remote sites for comparison. Participants were examined using a standardised protocol that included a questionnaire (self-administered or completed with the help of field staff), visual acuity (VA) testing on presentation and after correction, visual field testing, trachoma grading, and fundus and lens photography. The data were …

Hip Fracture Types In Men And Women Change Differently With Age, David A. Tanner, Marita Kloseck, Richard G. Crilly, Bert Chesworth, Jason Gilliland

Health Studies Publications

BACKGROUND: Hip fractures are expensive and a frequent cause of morbidity and mortality in the elderly. In most studies hip fractures have been viewed as a unitary fracture but recently the two main types of fracture (intertrochanteric and subcapital) have been viewed as two fractures with a different etiology and requiring a different approach to prevention. The relative proportion of intertrochanteric fractures increases with age in women. In previous studies no particular pattern in men has been noted. In this study, we explored changes in the relative proportion of the two fracture types with age in the two genders. METHODS: …

E-Mail Communication In Paediatrics: Ethical And Clinical Considerations, Susan Albersheim

Paediatrics Publications

E-mail has become a commonplace ‘procedure’ in medical practice because it is efficient and inexpensive. However, there are potential misuses and abuses of this form of written communication, with clinical and ethical implications. Common uses of e-mail in paediatics include general communication with colleagues in a professional setting; electronic formal consultation, in which patient confidentiality is paramount; electronic ‘curbside’ consultation, which may be perceived as a formal consultation; electronic discussion groups, which lack peer review; communication with current patients or their parents, which should be limited to simple, nonurgent issues; and communication with individuals seeking medical advice who are not …

Schedule For Ct Image Guidance In Treating Prostate Cancer With Helical Tomotherapy., G Beldjoudi, S Yartsev, G Bauman, Jerry J. Battista Dr., Jacob Van Dyk

Oncology Publications

The aim of this study was to determine the effect of reducing the number of image guidance sessions and patient-specific target margins on the dose distribution in the treatment of prostate cancer with helical tomotherapy. 20 patients with prostate cancer who were treated with helical tomotherapy using daily megavoltage CT (MVCT) imaging before treatment served as the study population. The average geometric shifts applied for set-up corrections, as a result of co-registration of MVCT and planning kilovoltage CT studies over an increasing number of image guidance sessions, were determined. Simulation of the consequences of various imaging scenarios on the dose …

Surgical Response To Catastrophe - Learning From Canada’S Experience Abroad, Vivian Mcalister

Data and Test Instruments

No abstract provided.

Dual-Task Interference: The Effects Of Verbal Cognitive Tasks On Upright Postural Stability In Parkinson's Disease, J. D. Holmes, M. E. Jenkins, Andrew M. Johnson, S. G. Adams, S. J. Spaulding

Occupational Therapy Publications

Although dual-task interference has previously been demonstrated to have a significant effect on postural control among individuals with Parkinson's disease, the impact of speech complexity on postural control has not been demonstrated using quantitative biomechanical measures. The postural stability of twelve participants with idiopathic Parkinson's disease and twelve healthy age-matched controls was evaluated under three conditions: (1) without a secondary task, (2) performing a rote repetition task and (3) generating a monologue. Results suggested a significant effect of cognitive load on biomechanical parameters of postural stability. Although both groups increased their postural excursion, individuals with Parkinson's disease demonstrated significantly reduced …

Running Enhances Spatial Pattern Separation In Mice., David J Creer, Carola Romberg, Lisa M Saksida, Henriette Van Praag, Timothy J Bussey

Brain and Mind Institute Researchers' Publications

Increasing evidence suggests that regular exercise improves brain health and promotes synaptic plasticity and hippocampal neurogenesis. Exercise improves learning, but specific mechanisms of information processing influenced by physical activity are unknown. Here, we report that voluntary running enhanced the ability of adult (3 months old) male C57BL/6 mice to discriminate between the locations of two adjacent identical stimuli. Improved spatial pattern separation in adult runners was tightly correlated with increased neurogenesis. In contrast, very aged (22 months old) mice had impaired spatial discrimination and low basal cell genesis that was refractory to running. These findings suggest that the addition of …