Behavior and Behavior Mechanisms Commons^™

Sex Differences In Mood And Anxiety-Related Outcomes In Response To Adolescent Nicotine Exposure, Tsun Hay Jason Ng

Electronic Thesis and Dissertation Repository

Nicotine dependence is causally linked to increased risk of mood/anxiety disorders in later life. Females are reported to experience a higher prevalence of anxiety/depressive disorders and challenges in smoking cessation therapies, suggesting a potential sex-specific response to nicotine exposure and mood/anxiety disorder risk. However, pre-clinical evidence of sex-specific responses to adolescent nicotine exposure is unclear. Thus, to determine any sex differences in anxiety/depressive-related outcomes, adolescent male and female Sprague Dawley rats received nicotine (0.4 mg/kg; 3x daily) or saline injections for 10 consecutive days, followed by behavioural testing, in-vivo electrophysiology and Western Blot analyses. Our results revealed that adolescent nicotine …

The Effects Of Prenatal Cannabis Exposure On The Basolateral Amygdala, Karen Kw Wong

Undergraduate Student Research Internships Conference

Clinical and preclinical studies indicate prenatal cannabis exposure (PCE) pathologically affects fetal brain development and may increase vulnerability to neuropsychiatric disorders, including schizophrenia and mood/anxiety disorders. In review research from our lab suggests that fetal exposure to Δ9-THC sex-selectively impairs mesocorticolimbic (MCL) circuit function. However, there is a distinct lack of focus on PCE models on the BLA. The BLA plays a central role within the MCL where it directly interacts with the VTA, PFC and HIPP. Importantly, our model exhibits significant VTA hyperdopaminergic activity, and sex-specific alterations to PFC/HIPP glutamate firing, alongside region- and sex-specific changes in dopamine (DA), …

The Effect Of Propionic Acid On The Habituation To Social And Non-Social Odour Cues In Adult Male Rats, Cashmeira-Dove P. Tyson

Electronic Thesis and Dissertation Repository

The enteric bacterial metabolite, propionic acid (PPA), elicits physiological and behavioural changes in rodents reminiscent of autism spectrum disorder (ASD). This includes abnormal sensory processing and social behaviour. ASD may contribute to social deficits through impaired habituation; therefore, the present study examined the effects of intraperitoneal PPA on the habituation to social and non-social odours. Adult male rats were injected daily with PPA or the vehicle control, and for 3 days, habituated to a conspecific odour or vanilla extract for 10 minutes. On day 4, rats were exposed to a novel conspecific odour or almond extract for 10 minutes to …

Using Meditation To Improve Measures Of Attention In Older Adults, Sabrina Ford

Electronic Thesis and Dissertation Repository

Age-related cognitive decline greatly impacts quality of life for older adults. Previous research has indicated that meditation may act as a neuroprotective factor to prevent age-related cognitive decline. This thesis sought to replicate previous findings and investigate if a four-week meditation intervention would improve sustained attention. Participants 60 years and older (n=27, 17 female) were recruited and assigned to a focused-attention (FA) meditation or relaxation group which met for four weeks, three times a week. Resting-state EEG was used to collect individual alpha peak frequency (iAPF) and frontal alpha asymmetry (FAA). The Sustained Attention to Response Task (SART) was also …

White Matter Inflammation And Executive Dysfunction: Implications For Alzheimer Disease And Vascular Cognitive Impairment, Alexander Levit

Electronic Thesis and Dissertation Repository

White matter integrity is crucial to healthy executive function, the cognitive domain that enables functional independence. However, in the ageing brain, white matter is highly vulnerable. White matter inflammation increases with age and Alzheimer disease (AD), which disrupts the normal function of white matter. This may contribute to executive dysfunction, but the relationship between white matter inflammation and executive function has not been directly evaluated in ageing nor AD. White matter is also particularly vulnerable to cerebrovascular disease, corresponding with the common presentation of executive dysfunction in vascular cognitive impairment (VCI). Thus, white matter may be an important substrate by …

Amelioration Of Prenatal Alcohol Effects By Environmental Enrichment In A Mouse Model Of Fasd, Aniruddho Chokroborty-Hoque

Electronic Thesis and Dissertation Repository

Maternal alcohol consumption during pregnancy results in a spectrum of behavioural and cognitive deficits collectively known as Fetal Alcohol Spectrum Disorders (FASD). Currently, little is know about if and how the external environment may modulate these deficits. I have used C57BL/6 mice to study this interaction between prenatal alcohol exposure and the postnatal environment. Alcohol exposure during synaptogenesis produces high levels of anxiety-like traits and decreased memory performance. Alcohol-exposed mice (and matched unexposed controls) were put in 'environmentally-enriched' conditions of voluntary exercise, physical activities and cognitive stimulation to ascertain the effects of a positive postnatal environment. The results show that …

Exploring The Neural Basis Of Top-Down Guided Action In Macaque Monkeys, Jessica M. Phillips

Electronic Thesis and Dissertation Repository

To thoroughly characterize any brain mechanism requires an appropriate animal model for invasive studies. An invaluable model system used toward a comprehension of cognitive neurophysiology is the macaque monkey. It is important to delineate similarities and limitations for this model in relation to the human brain and cognition. In this thesis, we have thus conducted three experiments to investigate putative generalizations between monkeys and humans regarding the neural processes associated with top-down action control in monkeys.

Our daily behaviour is largely comprised of automatic routine actions. The frequent repetition of certain behaviours in response to particular contexts can give rise …

Awareness Of Physical Activity Levels And Sedentary Behaviour: An Assessment Of Awareness Of Physical Activity Levels And Sedentary Behaviour Among Parents And Children, Tripat Simran Kaur Grewal

Electronic Thesis and Dissertation Repository

The purpose of this study was to assess awareness of physical activity and sedentary behaviour among parents and children aged 10-13 years. Associations between awareness and factors including age, BMI, gender, and obesity status were also examined. A total of 53 parent-child dyads participated in the study. Agreement between parent and child subjective measures (self-report) and objectively measured physical activity was examined to determine awareness. Most parents (87%) and children (83%) overestimated child moderate-vigorous physical activity (MVPA) beyond 30 minutes/day. The majority of parents (87%) and children (85%) also underestimated child sedentary behaviour by at least 3 hours/day. Older children …

Septohippocampal Gabaergic Neurons Mediate The Altered Behaviors Induced By N-Methyl-D-Aspartate Receptor Antagonists., Jingyi Ma, Siew Kian Tai, L Stan Leung

Physiology and Pharmacology Publications

We hypothesize that selective lesion of the septohippocampal GABAergic neurons suppresses the altered behaviors induced by an N-methyl-D-aspartate (NMDA) receptor antagonist, ketamine or MK-801. In addition, we hypothesize that septohippocampal GABAergic neurons generate an atropine-resistant theta rhythm that coexists with an atropine-sensitive theta rhythm in the hippocampus. Infusion of orexin-saporin (ore-SAP) into the medial septal area decreased parvalbumin-immunoreactive (GABAergic) neurons by ~80%, without significantly affecting choline-acetyltransferase-immunoreactive (cholinergic) neurons. The theta rhythm during walking, or the immobility-associated theta induced by pilocarpine, was not different between ore-SAP and sham-lesion rats. Walking theta was, however, more disrupted by atropine sulfate in ore-SAP than …