Language and the brain

Chapter 2 Response

Lateralization: Theory that suggests the hemisphers of the brain support different functionsAphasia: Language disorders caused by disease or traumaBroca's area: Labored speech, syntax errorsWernicke's area: Fluent speech but semantically incoherentBrain scans: Used to determine location of brain damage (ex: MRI, PET, fMRI, SPECT. )See the pictures at the right for examples of aphasia shown by brain scans)

c. 400 BCE: Plato and Aristotle speculate about language, but do not recognize the connection to the brainc. 377BCE: Hippocrates states, "[the brain is] the messenger of the understanding... c. 23-79BCE: Pliny the ELder is recorded suffering from aphasia "with the stroke of a stone."1745: Carl Linnaeus observes jargon aphasiaEarly 19th century: Franz Joseph Gall suggests phrenology (pseudoscience) and that the brain is a structured organ (localization)

Context

Language and the Brain

Aphasia

Hemispherectomy: a hemisphere of the brain is removed to prevent seizures (in children, language still develops, supporting the idea of brain plasticity at a young age. In adults the consequences are more severe)Split brains: removal of the corpus callosum; supports theory of lateralization

Specific Language Impairment: language impairment without brain trauma; may be geneticCritical period: hypothesis which suggests children learn language during a fixed period of time; supported by case studies of ferall children (Genie)

"We do not have definitive answers to the origin of language in the human brain."However, we do have valuable insights, tools, and theories to aid the ongoing search

Language and the brain

Where do we go from here?

SLI and the Critical Period

Language and Hemispheres

PET Scan

MRI Scan