Medicine and Health Sciences Commons^™

Music Therapy In Patients With Dementia And Behavioral Disturbance On An Inpatient Psychiatry Unit: Results From A Pilot Randomized Controlled Study., Joanna Thornley, Hussein Hirjee, Akshya Vasudev

Psychiatry Publications

The prevalence of dementia continues to grow worldwide due to an aging population and is projected to affect 65.7 million people by 2030 (World Health Organization, 2012). Behavioral and psychological symptoms of dementia (BPSD), including agitation, anxiety, aggression, depression, and psychosis, can occur in as much as 80% of the affected population, frequently necessitating psychiatric admission. Traditionally BPSD have been treated using pharmacological approaches. However, such medications could have serious adverse effects and additionally have limited efficacy in reducing such symptoms (Ballard et al., 2009).

Moving Towards A New Vision: Implementation Of A Public Health Policy Intervention, Ruta Valaitis, Marjorie Macdonald, Anita Kothari, Linda O’Mara, Sandra Regan, John Garcia, Nancy Murray, Heather Manson, Nancy Peroff-Johnston, Gayle Bursey, Jennifer Boyko

Health Studies Publications

Background

Public health systems in Canada have undergone significant policy renewal over the last decade in response to threats to the public’s health, such as severe acute respiratory syndrome. There is limited research on how public health policies have been implemented or what has influenced their implementation. This paper explores policy implementation in two exemplar public health programs -chronic disease prevention and sexually-transmitted infection prevention - in Ontario, Canada. It examines public health service providers’, managers’ and senior managements’ perspectives on the process of implementation of the Ontario Public Health Standards 2008 and factors influencing implementation.

Methods

Public health staff …

The Role Of Bone Sialoprotein In The Tendon-Bone Insertion, Ryan Marinovich, Yohannes Soenjaya, Gregory Q. Wallace, Andre Zuskov, Andrew Dunkman, Brian L. Foster, Min Ao, Kevin Bartman, Vida Lam, Amin Rizkalla, Frank Beier, Martha J. Somerman, David W. Holdsworth, Louis J. Soslowsky, François Lagugné-Labarthet, Harvey A. Goldberg

Bone and Joint Institute

© 2016 International Society of Matrix Biology. Tendons/ligaments insert into bone via a transitional structure, the enthesis, which is susceptible to injury and difficult to repair. Fibrocartilaginous entheses contain fibrocartilage in their transitional zone, part of which is mineralized. Mineral-associated proteins within this zone have not been adequately characterized. Members of the Small Integrin Binding Ligand N-linked Glycoprotein (SIBLING) family are acidic phosphoproteins expressed in mineralized tissues. Here we show that two SIBLING proteins, bone sialoprotein (BSP) and osteopontin (OPN), are present in the mouse enthesis. Histological analyses indicate that the calcified zone of the quadriceps tendon enthesis is longer …

Challenges In Mathematical Cognition: A Collaboratively-Derived Research Agenda, Lara Alcock, Daniel Ansari, Sophie Batchelor, Marie-Josee Bisson, Bert De Smedt, Camilla Gilmore, Silke M. Gobel, Minna Hannula-Sormunen, Jeremy Hodgen, Matthew Inglis, Ian Jones, Michele Mazzocco, Nicole Mcneil, Michael Schneider, Victoria Simms, Keith Weber

Brain and Mind Institute Researchers' Publications

This paper reports on a collaborative exercise designed to generate a coherent agenda for research on mathematical cognition. Following an established method, the exercise brought together 16 mathematical cognition researchers from across the fields of mathematics education, psychology and neuroscience. These participants engaged in a process in which they generated an initial list of research questions with the potential to significantly advance understanding of mathematical cognition, winnowed this list to a smaller set of priority questions, and refined the eventual questions to meet criteria related to clarity, specificity and practicability. The resulting list comprises 26 questions divided into six broad …

Evaluation Of Ct Perfusion Biomarkers Of Tumor Hypoxia, Qi Qi, Timothy Pok Chi Yeung, Ting-Yim Lee, Glenn Bauman, Cathie Crukley, Laura Morrison, Lisa Hoffman, Slav Yartsev

Anatomy and Cell Biology Publications

Background Tumor hypoxia is associated with treatment resistance to cancer therapies. Hypoxia can be investigated by immunohistopathologic methods but such procedure is invasive. A non-invasive method to interrogate tumor hypoxia is an attractive option as such method can provide information before, during, and after treatment for personalized therapies. Our study evaluated the correlations between computed tomography (CT) perfusion parameters and immunohistopathologic measurement of tumor hypoxia. Methods Wistar rats, 18 controls and 19 treated with stereotactic radiosurgery (SRS), implanted with the C6 glioma tumor were imaged using CT perfusion on average every five days to monitor tumor growth. A final CT …

Hyperpolarized 3he Magnetic Resonance Imaging Ventilation Defects In Asthma: Relationship To Airway Mechanics, Del Leary, Sarah Svenningsen, Fumin Guo, Swati Bhatawadekar, Grace Parraga, Geoffrey N Maksym

Medical Biophysics Publications

In patients with asthma, magnetic resonance imaging (MRI) provides direct measurements of regional ventilation heterogeneity, the etiology of which is not well-understood, nor is the relationship of ventilation abnormalities with lung mechanics. In addition, respiratory resistance and reactance are often abnormal in asthmatics and the frequency dependence of respiratory resistance is thought to reflect ventilation heterogeneity. We acquiredMRIventilation defect maps, forced expiratory volume in one-second (FEV1), and airways resistance (Raw) measurements, and used a computational airway model to explore the relationship of ventilation defect percent (VDP) with simulated measurements of respiratory system resistance (Rrs) and reactance (Xrs).MRIventilation defect maps were …

Functional Plasticity In Somatosensory Cortex Supports Motor Learning By Observing., Heather R Mcgregor, Joshua G A Cashaback, Paul L Gribble

Brain and Mind Institute Researchers' Publications

An influential idea in neuroscience is that the sensory-motor system is activated when observing the actions of others [1, 2]. This idea has recently been extended to motor learning, in which observation results in sensory-motor plasticity and behavioral changes in both motor and somatosensory domains [3-9]. However, it is unclear how the brain maps visual information onto motor circuits for learning. Here we test the idea that the somatosensory system, and specifically primary somatosensory cortex (S1), plays a role in motor learning by observing. In experiment 1, we applied stimulation to the median nerve to occupy the somatosensory system with …

Improving Vascular Access Outcomes: Attributes Of Arteriovenous Fistula Cannulation Success, Abram Oudshoorn

Nursing Publications

Background Arteriovenous fistulas (AVFs) are the preferred access for hemodialysis (HD) yet they are underutilized. Cannulation of the fistula is a procedure requiring significant skill development and refinement and if not done well can have negative consequences for patients. The nurses' approach, attitude and skill with cannulation impacts greatly on the patient experience. Complications from miscannulation or an inability to needle fistulas can result in the increased use of central venous catheters. Some nurses remain in a state of a 'perpetual novice' resulting in a viscous cycle of negative patient consequences (bruising, pain), further influencing patients' decisions not to pursue …

Propofol-Induced Frontal Cortex Disconnection: A Study Of Resting-State Networks, Total Brain Connectivity, And Mean Bold Signal Oscillation Frequencies., Pieter Guldenmund, Ithabi S Gantner, Katherine Baquero, Tushar Das, Athena Demertzi, Pierre Boveroux, Vincent Bonhomme, Audrey Vanhaudenhuyse, Marie-Aurélie Bruno, Olivia Gosseries, Quentin Noirhomme, Muriëlle Kirsch, Mélanie Boly, Adrian M Owen, Steven Laureys, Francisco Gómez, Andrea Soddu

Brain and Mind Institute Researchers' Publications

Propofol is one of the most commonly used anesthetics in the world, but much remains unknown about the mechanisms by which it induces loss of consciousness. In this resting-state functional magnetic resonance imaging study, we examined qualitative and quantitative changes of resting-state networks (RSNs), total brain connectivity, and mean oscillation frequencies of the regional blood oxygenation level-dependent (BOLD) signal, associated with propofol-induced mild sedation and loss of responsiveness in healthy subjects. We found that detectability of RSNs diminished significantly with loss of responsiveness, and total brain connectivity decreased strongly in the frontal cortex, which was associated with increased mean oscillation …

Revising The Bis/Bas Scale To Study Development: Measurement Invariance And Normative Effects Of Age And Sex From Childhood Through Adulthood., David Pagliaccio, Katherine R Luking, Andrey P Anokhin, Ian H Gotlib, Elizabeth P Hayden, Thomas M Olino, Chun-Zi Peng, Greg Hajcak, Deanna M Barch

Brain and Mind Institute Researchers' Publications

Carver and White's (1994) Behavioral Inhibition System/Behavioral Activation System (BIS/BAS) Scales have been useful tools for studying individual differences in reward-punishment sensitivity; however, their factor structure and invariance across development have not been well tested. In the current study, we examined the factor structure of the BIS/BAS Scales across 5 age groups: 6- to 10-year-old children (N = 229), 11- to 13-year-old early adolescents (N = 311), 14- to 16-year-old late adolescents (N = 353), 18- to 22-year-old young adults (N = 844), and 30- to 45-year-old adults (N = 471). Given poor fit of the standard 4-factor model (BIS, …

Caregiver Fatigue And Surrogate End-Of-Life Decision Making, Vivian Mcalister

Data and Test Instruments

The Supreme Court of Canada ruling in the case of Carter versus Canada (2015 SCC 5) concerns the right of a competent adult to a physician-assisted death if his or her suffering from a grievous and irremediable medical condition is intolerable. Discussions of the ruling have extended the parameters to include competent minors and advanced directives. They may also have altered the way we look at a separate but related end-of-life scenario, withdrawal of life-support; the number of anesthetic agents used to cover a patient during the withdrawal of life-support appear to have increased recently.How is it that all our …

Medial Prefrontal And Anterior Insular Connectivity In Early Schizophrenia And Major Depressive Disorder: A Resting Functional Mri Evaluation Of Large-Scale Brain Network Models, Jacob Penner, Kristen A. Ford, Reggie Taylor, Betsy Schaefer, Jean Theberge, Richard W. J. Neufeld, Elizabeth A. Osuch, Ravi S. Menon, Nagalingam Rajakumar, John M. Allman, Peter C. Williamson

Anatomy and Cell Biology Publications

Anomalies in the medial prefrontal cortex, anterior insulae, and large-scale brain networks associated with them have been proposed to underlie the pathophysiology of schizophrenia and major depressive disorder (MDD). In this study, we examined the connectivity of the medial prefrontal cortices and anterior insulae in 24 healthy controls, 24 patients with schizophrenia, and 24 patients with MDD early in illness with seed based resting state functional magnetic resonance imaging analysis using Statistical Probability Mapping. As hypothesized, reduced connectivity was found between the medial prefrontal cortex and the dorsal anterior cingulate cortex and other nodes associated with directed effort in patients …

Transient Pupil Dilation After Subsaccadic Microstimulation Of Primate Frontal Eye Fields., Sebastian J Lehmann, Brian D Corneil

Brain and Mind Institute Researchers' Publications

UNLABELLED: Pupillometry provides a simple and noninvasive index for a variety of cognitive processes, including perception, attention, task consolidation, learning, and memory. The neural substrates by which such cognitive processes influence pupil diameter remain somewhat unclear, although cortical inputs to the locus coeruleus mediating arousal are likely involved. Changes in pupil diameter also accompany covert orienting; hence the oculomotor system may provide an alternative substrate for cognitive influences on pupil diameter. Here, we show that low-level electrical microstimulation of the primate frontal eye fields (FEFs), a cortical component of the oculomotor system strongly connected to the intermediate layers of the …

Symbolic Numerical Magnitude Processing Is As Important To Arithmetic As Phonological Awareness Is To Reading, Kiran Vanbinst, Daniel Ansari, Bert De Smedt

Brain and Mind Institute Researchers' Publications

In this article, we tested, using a 1-year longitudinal design, whether symbolic numerical magnitude processing or children’s numerical representation of Arabic digits, is as important to arithmetic as phonological awareness is to reading. Children completed measures of symbolic comparison, phonological awareness, arithmetic, reading at the start of third grade and the latter two were retested at the start of fourth grade. Cross-sectional and longitudinal correlations indicated that symbolic comparison was a powerful domain-specific predictor of arithmetic and that phonological awareness was a unique predictor of reading. Crucially, the strength of these independent associations was not significantly different. This indicates that …

Motor And Hippocampal Dependent Spatial Learning And Reference Memory Assessment In A Transgenic Rat Model Of Alzheimer's Disease With Stroke, Jennifer L. Au, Nina Weishaupt, Hayley J. Nell, Shawn N. Whitehead, David F. Cechetto

Anatomy and Cell Biology Publications

Alzheimer's disease (AD) is a debilitating neurodegenerative disease that results in neurodegeneration and memory loss. While age is a major risk factor for AD, stroke has also been implicated as a risk factor and an exacerbating factor. The co-morbidity of stroke and AD results in worsened stroke-related motor control and AD-related cognitive deficits when compared to each condition alone. To model the combined condition of stroke and AD, a novel transgenic rat model of AD, with a mutated form of amyloid precursor protein (a key protein involved in the development of AD) incorporated into its DNA, is given a small …

Recovery Of Sleep Or Recovery Of Self? A Grounded Theory Study Of Residents' Decision Making Regarding How To Spend Their Nonclinical Postcall Time, Taryn S. Taylor, Jeff Nisker, Pim W. Teunissen, Tim Dornan, Lorelei Lingard

Paediatrics Publications

Purpose As resident work hours policies evolve, residents' off-duty time remains poorly understood. Despite assumptions about how residents should be using their postcall, off-duty time, there is little research on how residents actually use this time and the reasoning underpinning their activities. This study sought to understand residents' nonclinical postcall activities when they leave the hospital, their decision-making processes, and their perspectives on the relationship between these activities and their well-being or recovery. Method The study took place at a Liaison Committee on Medical Education-accredited Canadian medical school from 2012 to 2014. The authors recruited a purposive and convenience sample …

Toward A Mixed-Methods Research Approach To Content Analysis In The Digital Age: The Combined Content-Analysis Model And Its Applications To Health Care Twitter Feeds, Eradah O. Hamad, Marie Y. Savundranayagam, Jeffrey D. Holmes, Elizabeth Anne Kinsella, Andrew M. Johnson

Health and Rehabilitation Sciences Publications

BACKGROUND: Twitter’s 140-character microblog posts are increasingly used to access information and facilitate discussions among health care professionals and between patients with chronic conditions and their caregivers. Recently, efforts have emerged to investigate the content of health care-related posts on Twitter. This marks a new area for researchers to investigate and apply content analysis (CA). In current infodemiology, infoveillance and digital disease detection research initiatives, quantitative and qualitative Twitter data are often combined, and there are no clear guidelines for researchers to follow when collecting and evaluating Twitter-driven content.

OBJECTIVE: The aim of this study was to identify studies on …

Pulmonary Ct And Mri Phenotypes That Help Explain Chronic Pulmonary Obstruction Disease Pathophysiology And Outcomes, Eric A Hoffman, David A Lynch, R Graham Barr, Edwin J R Van Beek, Grace Parraga

Medical Biophysics Publications

Pulmonary x-ray computed tomographic (CT) and magnetic resonance imaging (MRI) research and development has been motivated, in part, by the quest to subphenotype common chronic lung diseases such as chronic obstructive pulmonary disease (COPD). For thoracic CT and MRI, the main COPD research tools, disease biomarkers are being validated that go beyond anatomy and structure to include pulmonary functional measurements such as regional ventilation, perfusion, and inflammation. In addition, there has also been a drive to improve spatial and contrast resolution while at the same time reducing or eliminating radiation exposure. Therefore, this review focuses on our evolving understanding of …

Imaging How And Where We Breathe Oxygen: Another Big Short?, Dante P I Capaldi, Fumin Guo, Grace Parraga

Medical Biophysics Publications

The Big Short tells the story of a small group of skeptics who profited from the financial crisis in 2007 by betting against collateralized (mortgage) debt obligations (CDO). Importantly, the novel paints a clear picture of the eccentric nature of contrarians who think divergently and against the grain or bet against an accepted truth or “sure” thing. In a similar manner, Ishii and co-workers’ recent work describes their team’s development of a pulmonary imaging technology that provides divergent and disruptive in vivo lung measurements of oxygen partial pressure in the context of the prevailing and longstanding consensus around FEV1 as …

The Expanding Phenotype Of Melas Caused By The M.3291t > C Mutation In The Mt-Tl1 Gene, E. Keilland, C. A. Rupar, Asuri N. Prasad, K. Y. Tay, A. Downie, C. Prasad

Bone and Joint Institute

Crown Copyright © 2016 Published by Elsevier Inc. m.3291T > C mutation in the MT-TL1 gene has been infrequently encountered in association with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS), however remains poorly characterized from a clinical perspective. In the following report we describe in detail the phenotypic features, long term follow up (> 7 years) and management in a Caucasian family with MELAS due to the m.3291T > C mutation and review the literature on m.3291T > C mutation. The clinical phenotype in the proposita included overlapping features of MELAS, MERRF (Myoclonic epilepsy and ragged-red fiber syndrome), MNGIE (Mitochondrial neurogastrointestinal …

Character, Incidence, And Predictors Of Knee Pain And Activity After Infrapatellar Intramedullary Nailing Of An Isolated Tibia Fracture, William Obremskey, Julie Agel, Kristin Archer, Philip To, Paul Tornetta, Mohit Bhandari, Gordon Guyatt, David W. Sanders, Emil H. Schemitsch, Marc Swiontkowski, Stephen Walter, Sheila Sprague, Diane Heels-Ansdell, Lisa Buckingham, Pamela Leece, Helena Viveiros, Tashay Mignott, Natalie Ansell, Natalie Sidorkewicz, Claire Bombardier, Jesse A. Berlin, Michael Bosse, Bruce Browner, Brenda Gillespie, Alan Jones, Peter O'Brien, Rudolf Poolman, Mark D. Macleod, Timothy Carey, Kellie Leitch, Stuart Bailey, Kevin Gurr, Ken Konito

Bone and Joint Institute

© Copyright 2015 Wolters Kluwer Health, Inc. All rights reserved. Objective: To study the activity and incidence of knee pain after sustaining an isolated tibia fracture treated with an infrapatellar intramedullary nail at 1 year. Design: Retrospective review of prospective cohort. Setting: Multicenter Academic and Community hospitals. Patients: Four hundred thirty-seven patients with an isolated tibia fracture completed a 12-month assessment on pain and self-reported activity. Intervention: Infrapatellar intramedullary nail. Outcomes: Demographic information, comorbid conditions, injury characteristics, and surgical technique were recorded. Knee pain was defined on a 1-7 scale with 1 being "no pain" and 7 being a "very …

Reaming Does Not Affect Functional Outcomes After Open And Closed Tibial Shaft Fractures: The Results Of A Randomized Controlled Trial, Carol A. Lin, Marc Swiontkowski, Mohit Bhandari, Stephen D. Walter, Emil H. Schemitsch, David Sanders, Paul Tornetta

Bone and Joint Institute

© Copyright 2015 Wolters Kluwer Health, Inc. All rights reserved. Objectives: We sought to determine the effect of reaming on 1-year 36-item short-form general health survey (SF-36) and short musculoskeletal function assessment (SMFA) scores from the Study to Prospectively Evaluate Reamed Intramedullary Nails in patients with Tibial Fractures. Design: Prospective randomized controlled trial.1319 patients were randomized to reamed or unreamed nails. Fractures were categorized as open or closed. Setting: Twenty-nine academic and community health centers across the US, Canada, and the Netherlands. Patients/Participants: One thousand three hundred and nineteen skeletally mature patients with closed and open diaphyseal tibia fractures. Intervention: …

Notochord Cells In Intervertebral Disc Development And Degeneration, Matthew R. Mccann, Cheryle A. Séguin

Bone and Joint Institute

© 2015 by the authors. All right reserved. The intervertebral disc is a complex structure responsible for flexibility, multi-axial motion, and load transmission throughout the spine. Importantly, degeneration of the intervertebral disc is thought to be an initiating factor for back pain. Due to a lack of understanding of the pathways that govern disc degeneration, there are currently no disease-modifying treatments to delay or prevent degenerative disc disease. This review presents an overview of our current understanding of the developmental processes that regulate intervertebral disc formation, with particular emphasis on the role of the notochord and notochord-derived cells in disc …

Differential Effect Of Clomipramine On Habituation And Prepulse Inhibition In Dominant Versus Subordinate Rats., Alvin Yang, Tahira Daya, Karen Carlton, Jin Hui Yan, Susanne Schmid

Brain and Mind Institute Researchers' Publications

Many patients with depression have comorbidities associated with an impairment of sensorimotor gating, such as e.g. schizophrenia, Parkinson Disease, or Alzheimer disease. Anti-depressants like clomipramine that modulate serotonergic or norepinephrinergic neurotransmission have been shown to impact sensorimotor gating, it is therefore important to study potential effects of clomipramine in order to rule out an exacerbation of sensorimotor gating impairment. Prior studies in animals and humans have been inconclusive. Since serotonin and norepinephrine levels are closely related to anxiety and stress levels and therefore to the social status of an animal, we tested the hypothesis that acute and chronic effects of …

Trajectories Of Symbolic And Nonsymbolic Magnitude Processing In The First Year Of Formal Schooling, Anna A. Matejko, Daniel Ansari

Brain and Mind Institute Researchers' Publications

Sensitivity to numerical magnitudes is thought to provide a foundation for higher-level mathematical skills such as calculation. It is still unclear how symbolic (e.g. Arabic digits) and nonsymbolic (e.g. Dots) magnitude systems develop and how the two formats relate to one another. Some theories propose that children learn the meaning of symbolic numbers by scaffolding them onto a pre-existing nonsymbolic system (Approximate Number System). Others suggest that symbolic and nonsymbolic magnitudes have distinct and non-overlapping representations. In the present study, we examine the developmental trajectories of symbolic and nonsymbolic magnitude processing skills and how they relate to each other in …

Structure And Function Of Gene Regulatory Networks Associated With Worker Sterility In Honeybees., Julia A Sobotka, Mark Daley, Sriram Chandrasekaran, Benjamin D Rubin, Graham J Thompson

Brain and Mind Institute Researchers' Publications

A characteristic of eusocial bees is a reproductive division of labor in which one or a few queens monopolize reproduction, while her worker daughters take on reproductively altruistic roles within the colony. The evolution of worker reproductive altruism involves indirect selection for the coordinated expression of genes that regulate personal reproduction, but evidence for this type of selection remains elusive. In this study, we tested whether genes coexpressed under queen-induced worker sterility show evidence of adaptive organization within a model brain transcriptional regulatory network (TRN). If so, this structured pattern would imply that indirect selection on nonreproductive workers has influenced …

Effects Of A Consistent Target Or Masker Voice On Target Speech Intelligibility In Two- And Three-Talker Mixtures., Fabienne Samson, Ingrid S Johnsrude

Brain and Mind Institute Researchers' Publications

When the spatial location or identity of a sound is held constant, it is not masked as effectively by competing sounds. This suggests that experience with a particular voice over time might facilitate perceptual organization in multitalker environments. The current study examines whether listeners benefit from experience with a voice only when it is the target, or also when it is a masker, using diotic presentation and a closed-set task (coordinate response measure). A reliable interaction was observed such that, in two-talker mixtures, consistency of masker or target voice over 3-7 trials significantly benefited target recognition performance, whereas in three-talker …

In Vivo Mri Signatures Of Hippocampal Subfield Pathology In Intractable Epilepsy., Maged Goubran, Boris C Bernhardt, Diego Cantor-Rivera, Jonathan C Lau, Charlotte Blinston, Robert R Hammond, Sandrine De Ribaupierre, Jorge G Burneo, Seyed M Mirsattari, David A Steven, Andrew G Parrent, Andrea Bernasconi, Neda Bernasconi, Terry M Peters, Ali R Khan

Brain and Mind Institute Researchers' Publications

OBJECTIVES: Our aim is to assess the subfield-specific histopathological correlates of hippocampal volume and intensity changes (T1, T2) as well as diff!usion MRI markers in TLE, and investigate the efficacy of quantitative MRI measures in predicting histopathology in vivo.

EXPERIMENTAL DESIGN: We correlated in vivo volumetry, T2 signal, quantitative T1 mapping, as well as diffusion MRI parameters with histological features of hippocampal sclerosis in a subfield-specific manner. We made use of on an advanced co-registration pipeline that provided a seamless integration of preoperative 3 T MRI with postoperative histopathological data, on which metrics of cell loss and gliosis were quantitatively …

Category Learning In Older Adulthood: A Study Of The Shepard, Hovland, And Jenkins (1961) Tasks., Rahel Rabi, John Paul Minda

Brain and Mind Institute Researchers' Publications

Shepard, Hovland, and Jenkins (1961) examined the categorization abilities of younger adults using tasks involving single-dimensional rule learning, disjunctive rule learning, and family resemblance learning. The current study examined category learning in older adults using this well-known category set. Older adults, like younger adults, found category tasks with a single relevant dimension the easiest to learn. In contrast to younger adults, older adults found complex disjunctive rule-based categories harder to learn than family resemblance based categories. Disjunctive rule-based category learning appeared to be the most difficult for older adults to learn because this category set placed the heaviest demands on …

The Representational-Hierarchical View Of Pattern Separation: Not Just Hippocampus, Not Just Space, Not Just Memory?, B. A. Kent, M. Hvoslef-Eide, L. M. Saksida, T. J. Bussey

Brain and Mind Institute Researchers' Publications

Pattern separation (PS) has been defined as a process of reducing overlap between similar input patterns to minimize interference amongst stored representations. The present article describes this putative PS process from the "representational-hierarchical" perspective (R-H), which uses a hierarchical continuum instead of a cognitive modular processing framework to describe the organization of the ventral visual perirhinal-hippocampal processing stream. Instead of trying to map psychological constructs onto anatomical modules in the brain, the R-H model suggests that the function of brain regions depends upon what representations they contain. We begin by discussing a main principle of the R-H framework, the resolution …