Chapter 3: Medical and Scientific Disciplines Flashcards
What three health bodies are involved with SLT?
- Royal College of Speech and Language Therapists.
- Quality Assurance Agency for Higher Education.
- Health and Care Professions Council.
What does a prevalence of a disorder mean?
The number of individuals in a population who have the disorder at a specific period of time.
E.g. percentage of the population.
What does the incidence of a disorder mean?
The number of individuals who develop a disease/disorder during a particular time period, usually a month/year.
What variables affect the distribution of diseases/disorders? 4
- Sex.
- Race.
- Ethnicity.
- Socioeconomic status.
What is the study of aetiology?
Study of medical causes of diseases/disorders.
Medical cause of a communication disorder can often be identified e.g. Down syndrome.
What does functional disorder mean?
Disorder that lacks medical aetiology.
Functional voice disorder label used when there is impairment of the use/function of the vocal apparatus.
Can relate to psychogenic origins (e.g. stuttering) - psychogenic voice disorder label used.
What is the study of epidemiology?
Study of distribution and determinants of diseases/disorders in populations.
Key concepts - prevalence and incidence.
What is the difference between proximal aetiology and distal aetiology?
Proximal - direct causes of a disorder.
Distal - cause via an intermediary factor.
What is the difference between anatomy and physiology?
Anatomy - structure of the organs.
Physiology - function of the organs.
Why would the knowledge of cell biology be useful?
Includes the structure and function of hair cells of the cochlea and how these cells may be degraded via illness e.g. meningitis and injury e.g. noise exposure.
Why would the study of histology be useful?
Study of tissues - can help understand vocal fold structure and function.
Lamina propria lies deep in the squamous epithelium vocal fold.
Three layers - superficial, intermediate and deep.
Why would the knowledge of genetics be useful?
To understand genetic syndromes e.g. fragile X syndrome and autism - can explain higher male ratio.
4-5:1 imprinted X-liability threshold model.
Why is knowledge of respiration useful?
Reduced breath speech support can affect intelligibility e.g. cerebal palsy.
Reduced vocal volume e.g. Parkinson’s disease.
Why is knowledge of the cardiovascular systems useful?
Children with congenital heart disease are at risk of brain injury.
Relationship between cardiovascular disease and cerebrovascular accidents.
E.g. blood clots (atherosclerosis) can travel to the brain and prevent oxygenated blood from reaching brain tissue - stroke.
Why is knowledge of the central nervous system useful?
Relates to the brain and spinal cord.
Brain contains neuroanatomical areas related to speech and language e.g. primary motor context, Broca’s area and Wernicke’s area.
Why is knowledge of the peripheral nervous system useful?
31 spinal nerves and 12 cranial nerves.
Cranial nerves control a lot of facial muscles.
E.g. orbicularis oris (sphincter muscle which encircles the lips).
Spinal nerves e.g. pherenic nerve controls diaphragm and intercostal muscles.
Why is knowledge of the sensory systems useful?
Hearing, vision and olfaction are vital for communication and swallowing.
Visual - facial expressions and gestures.
What are some examples of congenital malformations?
Cleft lip and palate.
Micrognathia (undeveloped mandible - jaw) e.g. Pierre Robin syndrome.
Macroglossia (large tongue).
What happens to the body growing up?
During preschool period - brain enlarges x4.
Puberty - larynx descends and dimensions of the infraglottic sagittal and transverse planes increase.
Changes in mass and size is greater for males.
Male average frequency - 130 Hz at 18 years old.
Female average frequency - 220-225 Hz at 18 years old.
CASE STUDY - Cleft Palate.
Prevalence? How is speech affected and why?
9.92 per 10,000 (2011) - higher in boys.
Highest rates in the white population of California.
Hypernasal speech due to velopharyngeal incompetence.
Closure of the velopharyngeal port is often not possible due to anatomical and physiological reasons.
What happens to the lungs as an adult?
Lungs mature by 20-25 years age.
Decrease in maximum inspiratory pressure can lead to inadequate ventilation and impaired clearance of airway secretions.
What can happen to the ears as an adult?
Ossicular chain in the middle ear may be impaired - onset of otosclerosis.
E.g. new bone growth on the anterior stapes footplate, leading to the fixation of the stapes - hearing loss.
Treated by stapedectomy surgery.
Mean age for surgery - 43.57 years old.
What are some examples of anatomy not developing properly in the pre-natal period? 3
Cleft lip and palate.
Micrognathia (undersized jaw).
Atresia (absence) of the ear canal.
Cerebral Palsy CASE STUDY
Prevalence? Causes (4)? Detectable stat? How is it classified?
Motor disability - prevalence 1.5-2.5 per 1,000 live births.
Number of aetiologies (causes) e.g. abnormal neurodevelopment in pre-natal period, hypoxia (reduced oxygen supply), infections such as congenital cytomegalovirus and neonatal meningitis.
17% cases - undetectable via MR/CT scanning.
Classified via motor impairment (e.g. spasticity hemiplegia - tight muscle tone on one half of the body) and impairment distribution (e.g. hemiplegia).
