1. Regional Cerebral Blood Flow Anne Marie KatharinaDanielMary

2. Overview Subjects Subjects Goals and Study Goals and Study Methods Methods Results Results

3. Subjects for the Test 2 Groups 6 deaf persons 20 – 30 years age 9 hearing persons 19 – 45 years of age Deaf parents Right-handed No neuro disease Common factors

4. Goals and Study similarities between signed and spoken language similarities between signed and spoken language both seem to activate much the same regions in the brain both seem to activate much the same regions in the brain more occipital activation in sign language more occipital activation in sign language sign language seems to involve the right hemisphere sign language seems to involve the right hemisphere study: compare sign language lateralization and localization between hearing and deaf children of deaf parents study: compare sign language lateralization and localization between hearing and deaf children of deaf parents

5. Methods high resolution rCBF high resolution rCBF Swedish novel was translated into Swedish sign language Swedish novel was translated into Swedish sign language presented by a deaf man signing presented by a deaf man signing instruction: focus on story instruction: focus on story retell story retell story Activation was compared during sign language and rest Activation was compared during sign language and rest

6. Results both groups show a high bifrontal activation during rest both groups show a high bifrontal activation during rest - deaf group exhibited more activation in the parieto-occipital lobe - (highly significant) - hearing signers used more temporal areas - it seems that deafness and not the early learning of sign language that leads to enhanced right hemisphere activation enhanced right hemisphere parieto-occipital activation in this group is an effect: enhanced right hemisphere parieto-occipital activation in this group is an effect: - lack of auditory stimulation and of - early learning of a visual-spatial language