An Investigation of Motivation in the Spontaneously Hypertensive Rat (SHR), a Rodent Model of ADHD
Mentor 1
Rodney Swain
Location
Union Wisconsin Room
Start Date
5-4-2019 1:30 PM
End Date
5-4-2019 3:30 PM
Description
Attention Deficit Hyperactivity Disorder (ADHD) is one of the most commonly diagnosed childhood neurobehavioral disorders. ADHD is characterized by three core behavioral deficits, hyperactivity, inattention, and impulsivity. These deficits significantly hinder the daily functioning of those diagnosed. Furthermore, children with ADHD have problems with motivation and often require larger, more frequent rewards in order to complete a task. While the etiology of the disorder is largely unknown, we do know that various areas of the brain, including the cerebellum, have abnormalities that warrants further investigation. In this study, we used the Spontaneously Hypertensive Rat (SHR), a rodent model of ADHD that exhibits all of the core deficits. The goal of the current study was to further validate the SHR as a model of ADHD by training rats in an operant conditioning breakpoint paradigm to investigate motivation. Twelve male SHR and 12 male control rats were trained on a Progressive Ratio schedule that increased in difficulty until the rats reached their breakpoint, which was defined as the point at which the animals stop working. The breakpoint served as a measure of motivation and the higher the breakpoint, the more motivated the animal was. Results show that the SHR animals had a significantly lower breakpoint compared to the control animals, indicating that they gave up on the task much sooner. Our findings that the SHR model of ADHD displays problems with motivation further adds to the reliability of the model. Future analyses include an examination of the cerebellum anatomy that may provide an explanation for why the motivational behavior is altered in the SHR model of ADHD.
An Investigation of Motivation in the Spontaneously Hypertensive Rat (SHR), a Rodent Model of ADHD
Union Wisconsin Room
Attention Deficit Hyperactivity Disorder (ADHD) is one of the most commonly diagnosed childhood neurobehavioral disorders. ADHD is characterized by three core behavioral deficits, hyperactivity, inattention, and impulsivity. These deficits significantly hinder the daily functioning of those diagnosed. Furthermore, children with ADHD have problems with motivation and often require larger, more frequent rewards in order to complete a task. While the etiology of the disorder is largely unknown, we do know that various areas of the brain, including the cerebellum, have abnormalities that warrants further investigation. In this study, we used the Spontaneously Hypertensive Rat (SHR), a rodent model of ADHD that exhibits all of the core deficits. The goal of the current study was to further validate the SHR as a model of ADHD by training rats in an operant conditioning breakpoint paradigm to investigate motivation. Twelve male SHR and 12 male control rats were trained on a Progressive Ratio schedule that increased in difficulty until the rats reached their breakpoint, which was defined as the point at which the animals stop working. The breakpoint served as a measure of motivation and the higher the breakpoint, the more motivated the animal was. Results show that the SHR animals had a significantly lower breakpoint compared to the control animals, indicating that they gave up on the task much sooner. Our findings that the SHR model of ADHD displays problems with motivation further adds to the reliability of the model. Future analyses include an examination of the cerebellum anatomy that may provide an explanation for why the motivational behavior is altered in the SHR model of ADHD.
