Aphasia is an acquired communication disorder affecting language production and comprehension. It is caused by brain injury, most commonly from stroke. Affects about two million Americans, more common than Parkinson's or cerebral palsy. Can occur in all ages, genders, nationalities, and races
Apraxia is a motor disorder caused by brain damage affecting motor planning. Can be congenital or acquired from brain injury, stroke, or neurodegenerative diseases. Most commonly affects dominant hemisphere, particularly frontal and parietal lobes
There are two types of TH sounds: voiceless (think) and voiced (they). Voiceless TH requires more air production, while voiced TH has less. Children should be able to say voiceless TH between 4.55-7 years. Voiced TH should be mastered between 5-8 years
Speech-language pathology evaluates and treats communication disorders across lifespan. Professionals include speech-language pathologists (SLPs) and speech therapists (SLTs). ASHA and Speech Pathology Australia regulate the profession
Stuttering disrupts natural speech flow and can be developmental or chronic. Over 3 million Americans stutter, with 5% of children experiencing it. Males are four times more likely to have stuttering issues
Muteness is the absence of speech with or without hearing others' speech. Can be temporary or permanent due to various causes. May involve physiological issues, psychological trauma, or neurological disorders