Filtering by
- Creators: Mann, Annika
- Creators: School of Life Sciences
- Member of: Barrett, The Honors College Thesis/Creative Project Collection
Speech motor learning is important for learning to speak during childhood and maintaining the speech system throughout adulthood. Motor and auditory cortical regions play crucial roles in speech motor learning. This experiment aimed to use transcranial alternating current stimulation, a neurostimulation technique, to influence auditory and motor cortical activity. In this study, we used an auditory-motor adaptation task as an experimental model of speech motor learning. Subjects repeated words while receiving formant shifts, which made the subjects’ speech sound different from their production. During the adaptation task, subjects received Beta (20 Hz), Alpha (10 Hz), or Sham stimulation. We applied the stimulation to the ventral motor cortex that is involved in planning speech movements. We found that the stimulation did not influence the magnitude of adaptation. We suggest that some limitations of the study may have contributed to the negative results.
Cellular hypertrophy is an anaerobically-based, adaptive process that mammalian skeletal muscle undergoes in response to damage resulting from unaccustomed force generation by the muscle. Hypertrophy allows for the muscle tissue to recover from the immediate injury and also to be rebuilt more capable of withstanding producing the same amount of force without injury, should it happen again. This means the end result of an adapted muscle is an overall more efficient tissue. The ability to regenerate after damage to the structure and function of the muscle tissue is a highly orchestrated event involving multiple steps and key events to occur. Most briefly, a mechanical load is attempted to be lifted but due to demanding a high amount of contractile force to lift, it causes microdamage to the structural and contractile elements of muscle fiber’s sarcomeres. In addition to an inflammatory response, satellite cells, as a part of a myogenic response, are activated to invade the fiber and then permanently reside inside to produce new proteins that will replace the damaged and necrotized proteins. This addition of cellular content, repeated over multiple times, results in the increased diameter of the fibers and manifests in the visual appearance of skeletal muscle hypertrophy. These steps have been listed off devoid of the contexts in which it takes for these to occur and will be addressed within this thesis.
Disclaimer: The initial goal of this project was to present this information as a podcast episode as a part of a series aimed at teaching the general public about human physiological adaptations. Due to the circumstances with COVID-19 we were unable to meet to make a final recording of the podcast episode. A recording of a practice session recorded earlier in the year has been uploaded instead and is therefore only a rough draft.