Positron Emission Tomography (PET) is a technique used to investigate the functional activity of the brain. The PET technique allows doctors to study the normal biochemical and metabolic processes of the central nervous system of normal individuals and patients with neurologic illnesses without physical / structural damage to the brain. Radioactive water H215O in PET scans permits good visualization of areas of the brain related to speech.

Most of the PET scan studies conducted have concentrated on learning about how language is formed and decoded. Few studies have been conducted on speech production. This study aims to use radioactive water (H215O) and Positron Emission Tomography (PET scan) to measure blood flow to different areas of the brain in order to better understand the mechanisms involved in speech motor control.

When a region of the brain is active, it uses more fuel in the form of oxygen and sugar (glucose). As the brain uses more fuel it produces more waste products, carbon dioxide and water. Blood carries fuel to the brain and waste products away from the brain. As brain activity increases blood flow to and from the area of activity increases also. Knowing these facts, researchers can use radioactive chemicals (H215O) and PET scans to observe what areas of the brain are receiving more blood flow.

Researchers will ask patients to perform tasks that will affect speech, voice, and language. At the same time patients will undergo a PET scan. The tasks are designed to help researchers observe the blood flow to brain areas associated with voicebox (laryngeal) functions, movement of muscles in the jaw, tongue, and mouth, and other aspects of motor speech.

Special studies will be conducted to evaluate how certain therapies and tasks can draw out symptoms in illnesses in which speech and language are affected. Results of these tests will be used in other studies to evaluate the neurologic mechanisms of diseases like Tourette's syndrome and parkinson's disease.

Condition	Treatment or Intervention
Communication Disorder Healthy Stuttering Tourette Syndrome Voice Disorder	Drug: Radioactive Water

Further Study Details: 

Expected Total Enrollment:  727

The H215O PET, fMRI, and EEG neuroimaging method will be used to study the CNS mechanisms involved in speech production. Sets of controlled tasks intended to isolate and activate distinct elements of motor speech and voice will be administered to normal controls and patients with speech disorders. Tasks will be designed to produce sustained motor behaviors over the 4 minute period of H215O uptake. Individual scans will generally be performed during each task condition. Arterial blood will be sampled to permit full quantification of the PET data.

Generalized tasks will be administered both to normal controls and patients with neurological disorders affecting speech, voice and language. These tasks are designed to evaluate the regional cerebral blood flow patterns associated with elementary laryngeal functions, oral, lingual and jaw movements, as well as linguistic and non-linguistic speech production. Other generalized tasks will evaluate prosodic and affective elements of motor speech, premotor mechanisms in speech motor control and regional cerebral blood flow correlates of speech learning.

A separate series of studies will evaluate therapeutic interventions or behavioral tasks designed to attenuate symptoms in illnesses in which speech and language are affected. These will be utilized in a repeated measures design to evaluate CNS mechanisms underlying dysfluency in patients with stuttering, and limb vs. speech motor symptoms in Tourette's syndrome, Parkinson's disease and other neurological disorders.

Genders Eligible for Study:  Both

Accepts Healthy Volunteers

Criteria

INCLUSION CRITERIA:
Subjects will be selected from a population of patients with post-stroke aphasia.
No preference or exclusion will be granted due to gender, religion, race or ethnic background.
Non-pregnant, non-breast feeding, age and sex matched normal subjects will be recruited to provide control values.
Recruitment will be limited to those 18 years to 80 years in age.
EXCLUSION CRITERIA:
Children will be excluded form this protocol because they do not represent members of the population at risk.
Pregnant women are excluded because the effects of the MRI on the fetus have not been established.

Maryland
      National Institute on Deafness and Other Communication Disorders (NIDCD), 9000 Rockville Pike,  Bethesda,  Maryland,  20892,  United States; Recruiting

Study ID Numbers:  920178; 92-DC-0178
Record last reviewed:  April 19, 2004
Last Updated:  November 23, 2004
Record first received:  November 3, 1999
ClinicalTrials.gov Identifier:  NCT00001308
Health Authority: United States: Federal Government
ClinicalTrials.gov processed this record on 2005-04-08