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Reversible Cooling-Induced Deactivations To Study Cortical Contributions To Obstacle Memory In The Walking Cat, Carmen Wong, Stephen G. Lomber

Brain and Mind Institute Researchers' Publications

On complex, naturalistic terrain, sensory information about an environmental obstacle can be used to rapidly adjust locomotor movements for avoidance. For example, in the cat, visual information about an impending obstacle can modulate stepping for avoidance. Locomotor adaptation can also occur independent of vision, as sudden tactile inputs to the leg by an expected obstacle can modify the stepping of all four legs for avoidance. Such complex locomotor coordination involves supraspinal structures, such as the parietal cortex. This protocol describes the use of reversible, cooling-induced cortical deactivation to assess parietal cortex contributions to memory-guided obstacle locomotion in the cat. Small …

Sleep-Dependent Motor Sequence Memory Consolidation In Individuals With Periodic Limb Movements, Valya Sergeeva, Jeremy Viczko, Laura B. Ray, Adrian M. Owen, Stuart M. Fogel

BrainsCAN Publications

© 2017 Elsevier B.V. Periodic limb movements (PLMs) during sleep increase with age and are associated with striatal neurodegeneration and dopamine deficiency. Limb movements are often associated with disruptions to non-rapid eye movement (NREM) sleep. Motor skill memory consolidation recruits the striatum, and learning-dependent striatal activation is associated with NREM sleep. Therefore, we investigated whether de novo individuals who significantly experience elevated levels of PLMs but have not been formally diagnosed with periodic limb movement disorder had learning and sleep-related memory deficits and whether these deficits were related to sleep quality and symptom severity. In total, 14 adults with significantly …

The Tapestry Of Memory, Kathryn M. Lawson

Electronic Thesis and Dissertation Repository

Rationality points to the complete annihilation and end of a life when the body perishes, and yet when a loved one dies we continue to experience that person in a myriad of ways. The focus of this thesis will be a phenomenological exploration of the earthly afterlife of those we have loved and lost. By positing the subject as always intersubjective and as temporal in nature, this thesis will investigate how we continue to create and interact with the deceased upon the earth. In the introduction, this work will be placed in the context of the phenomenological tradition. The first …

Mechanisms Involved In The Assessment Of Cumulative Long-Term Familiarity Of Object Concepts: An Erp Study, Haopei Yang

Electronic Thesis and Dissertation Repository

We investigated the sensitivity of ERP components implicated in recognition memory to degree of experimentally controlled and lifetime cumulative exposures during explicit memory judgements. A parietally distributed ERP component spanning both the FN400/N400 and the LPC time windows tracked both types of judgements. This effect appears to be an LPC effect with an early onset, and differs from previously reported effects of repetition linked to implicit memory. Based on recent evidence, we interpreted it as response-related evidence accumulation processes that are in line with both single-process models and continuous dual-process models. We also observed more positive ERPs in the left …

Brain Biomarkers And Pre-Injury Cognition Are Associated With Long-Term Cognitive Outcome In Children With Traumatic Brain Injury, Amy A Wilkinson, Maureen Dennis, Nevena Simic, Margot J Taylor, Benjamin R Morgan, Helena Frndova, Karen Choong, Craig Campbell, Douglas Fraser, Vicki Anderson, Anne-Marie Guerguerian, Russell Schachar, Jamie Hutchison

Paediatrics Publications

BACKGROUND: Children with traumatic brain injury (TBI) are frequently at risk of long-term impairments of attention and executive functioning but these problems are difficult to predict. Although deficits have been reported to vary with injury severity, age at injury and sex, prognostication of outcome remains imperfect at a patient-specific level. The objective of this proof of principle study was to evaluate a variety of patient variables, along with six brain-specific and inflammatory serum protein biomarkers, as predictors of long-term cognitive outcome following paediatric TBI.

METHOD: Outcome was assessed in 23 patients via parent-rated questionnaires related to attention deficit hyperactivity disorder …

Individual Differences In The Allocation Of Visual Attention During Navigation, Mikayla Keller

Electronic Thesis and Dissertation Repository

There are large individual differences in the ability to create an accurate mental representation (i.e., a cognitive map) of a novel environment, yet the factors underlying cognitive map accuracy remain unclear. Given the roles that landmarks and cognitive map accuracy play in successful navigation, the current study examined whether differences in the landmarks that individuals look at while navigating are related to differences in cognitive map accuracy. Participants completed a battery of spatial tests: some that assessed spatial skills prior to a navigation task, and others that tested memory for the environment following exploration of a virtual world. Results indicated …

Cerebral Lactate Metabolism And Memory: Implications For Alzheimer's Disease, Richard Andrew Harris

Electronic Thesis and Dissertation Repository

Alzheimer’s disease (AD) is a neurodegenerative disease characterized by amyloid plaques that are comprised of aggregated amyloid-beta peptides. These toxic proteins promote mitochondrial dysfunction and neuronal cell death. A shift in metabolism away from oxidative phosphorylation and toward aerobic glycolysis, with the concomitant production of lactate, affords neurons a survival advantage against amyloid-beta toxicity. Recent evidence now suggests that aerobic glycolysis in the brain plays a critical role in supporting synaptic plasticity, learning, and memory. However, the role of aerobic glycolysis and lactate metabolism in AD-mediated cognitive decline is unknown. My objective was to test the hypotheses that aerobic glycolysis …

Image Memory For Hyperpalatable Foods In University Aged Females, Leila M. Mackay

Brescia Psychology Undergraduate Honours Theses

Hyperpalatable foods are high in sugar and/or fat and highly processed. These foods increase dopamine in the brain similar to other rewards, such as drugs of abuse, producing pleasure and an enhanced drive to consume them. Undergraduate students (n = 44) completed an explicit memory task where they were asked if they recalled various types of food (high sugar, high fat, sugar+fat, fruits, vegetables and breads) and non-food images. Questionnaires evaluating eating patterns were also completed. It was hypothesized that hyperpalatable foods would be recalled better and faster than less-palatable foods or non-food images. The study found that hyperpalatable …

Sleep-Based Memory Processing Facilitates Grammatical Generalization: Evidence From Targeted Memory Reactivation., Laura J Batterink, Ken A Paller

Brain and Mind Institute Researchers' Publications

Generalization-the ability to abstract regularities from specific examples and apply them to novel instances-is an essential component of language acquisition. Generalization not only depends on exposure to input during wake, but may also improve offline during sleep. Here we examined whether targeted memory reactivation during sleep can influence grammatical generalization. Participants gradually acquired the grammatical rules of an artificial language through an interactive learning procedure. Then, phrases from the language (experimental group) or stimuli from an unrelated task (control group) were covertly presented during an afternoon nap. Compared to control participants, participants re-exposed to the language during sleep showed larger …

Mosaic Expression Of Atrx In The Mouse Central Nervous System Causes Memory Deficits, Renee J Tamming, Jennifer R Siu, Yan Jiang, Marco A M Prado, Frank Beier, Nathalie G Bérubé

Paediatrics Publications

The rapid modulation of chromatin organization is thought to play a crucial role in cognitive processes such as memory consolidation. This is supported in part by the dysregulation of many chromatin-remodelling proteins in neurodevelopmental and psychiatric disorders. A key example is ATRX, an X-linked gene commonly mutated in individuals with syndromic and nonsyndromic intellectual disability. The consequences of Atrx inactivation for learning and memory have been difficult to evaluate because of the early lethality of hemizygous-null animals. In this study, we evaluated the outcome of brain-specific Atrx deletion in heterozygous female mice. These mice exhibit a mosaic pattern of ATRX …

Pearls And Perils Of Pupillometry Using A Webcam, Mason Kadem, Rhodri Cusack

Undergraduate Honors Posters

Current methods to measure infants’ cognitive repertoire (i.e., collection of cognitive abilities) are limited. Previous testing paradigms required acquisition of non-age contextualized responses, and relied on measures that involved acquisition of other functions (e.g., language, motor). In addition to response limitations, cognitive functions may be difficult to observe in infants due to the difficulty in infant recruitment. Online testing has increased infant recruitment efforts and physiological responses have bypassed the motor, behavioural and linguistic limitations of infants. Recently, it has been shown that heart rate measures can be acquired through a webcam. Another feasible and reliable physiological measure is pupillometery, …