Older adults are disproportionately affected by swallowing impairment, or dysphagia, a condition that can lead to increased morbidity and death. Delayed initiation of swallowing is a common and devastating pathophysiology of neurogenic dysphagia, and is also experienced by healthy older adults, making functional swallowing less safe. Previously we have shown that healthy older adults have significantly delayed swallowing onset as well as increased neural activation in the primary sensory-motor cortex (SMI), a phenomenon absent in younger adults. However, it is still not known if differences in activation of SMI are responsible for delays in swallowing initiation or its consequence with advancing age. The goals of this proposal are;(1) to understand the functional role of SMI on swallowing initiation;(2) to characterize the effect of aging on swallowing initiation with transient cortical disruption;and, (3) for Dr. Humbert to obtain specialized training in neuroscience, sensory-motor control, and aging swallowing physiology. The overall hypothesis is that transient disruption of SMI will produce measurable delays in swallowing initiation in young and old adults, but older adults will have more pronounced deficits. We will apply single-pulse transcranial magnetic stimulation (TMS) to the bilateral SMI laryngeal representation with concurrent video fluoroscopy and electromyography (EMG) during swallowing at various temporal intervals to examine changes in swallowing onset in healthy young and old adults. This investigation will determine whether cortical areas are involved in initiating swallowing as well as the importance of timing on this function. We will also be able to determine whether older adults have a decreased ability to counteract the disruptions to SMI by testing young and old adults. The results from this proposed investigation is significant because the geriatric population is more prone to developing dysphagia due to neurological impairment such as Alzheimer's disease, stroke, and Parkinson's disease. The knowledge gained in this study will become the foundation to develop scientifically sound strategies to reduce this common health care problem that burdens our society.
This investigation is relevant to public health because it will determine whether older adults have a decreased ability to counteract disruptions to the brain, causing delays in swallowing. This is significant because the geriatric population is more likely to develop swallowing impairment due to Alzheimer's disease, stroke, and Parkinson's disease. The knowledge gained in this study will help to develop interventions to reduce this common health care problem that burdens our society.
|Calvo, Irene; Sunday, Kirstyn L; Macrae, Phoebe et al. (2017) Effects of chin-up posture on the sequence of swallowing events. Head Neck 39:947-959|
|Young, Jennifer L; Macrae, Phoebe; Anderson, Cheryl et al. (2015) The Sequence of Swallowing Events During the Chin-Down Posture. Am J Speech Lang Pathol 24:659-70|
|Azola, Alba M; Greene, Lindsey R; Taylor-Kamara, Isha et al. (2015) The Relationship Between Submental Surface Electromyography and Hyo-Laryngeal Kinematic Measures of Mendelsohn Maneuver Duration. J Speech Lang Hear Res 58:1627-36|
|Humbert, Ianessa A; Christopherson, Heather; Lokhande, Akshay (2015) Surface electrical stimulation perturbation context determines the presence of error reduction in swallowing hyolaryngeal kinematics. Am J Speech Lang Pathol 24:72-80|
|Macrae, Phoebe; Anderson, Cheryl; Humbert, Ianessa (2014) Mechanisms of airway protection during chin-down swallowing. J Speech Lang Hear Res 57:1251-8|
|González-Fernández, Marlís; Humbert, Ianessa; Winegrad, Heather et al. (2014) Dysphagia in old-old women: prevalence as determined according to self-report and the 3-ounce water swallowing test. J Am Geriatr Soc 62:716-20|
|Macrae, Phoebe; Anderson, Cheryl; Taylor-Kamara, Isha et al. (2014) The effects of feedback on volitional manipulation of airway protection during swallowing. J Mot Behav 46:133-9|
|Humbert, Ianessa A; Christopherson, Heather; Lokhande, Akshay et al. (2013) Human hyolaryngeal movements show adaptive motor learning during swallowing. Dysphagia 28:139-45|
|Humbert, Ianessa A; German, Rebecca Z (2013) New directions for understanding neural control in swallowing: the potential and promise of motor learning. Dysphagia 28:1-10|
|Humbert, Ianessa A; Michou, Emilia; MacRae, Phoebe R et al. (2012) Electrical stimulation and swallowing: how much do we know? Semin Speech Lang 33:203-16|
Showing the most recent 10 out of 12 publications