5. Thinking, Planning, Language Flashcards
How does the brain understand perceptions?
Relies on associations assembled from previous experience.
How does the brain work around its limited short-term memory?
It builds simple representations of things as references
Semantic memory
Form of declarative knowledge that includes facts and data. Construction of representations of things relies on semantic memory.
Concept cells
Specific, single cells that fire when looking at a particular person, but remain quiet when looking at something else. Work together in assemblies. Form basis of semantic memory. Located in the temporal lobe, which specializes in object recogntion
D.B.O
Case of a 72-year old man who had multiple strokes. He could only identify 1 out of every 20 common objects by sight, but could easily identify objects by feeling or hearing them. It was concluded that the strokes prevented visual input from being conveyed to the anterior temporal regions where semantic processing occurs
Agnosia
Like D.B.O. Damage to certain areas of the temporal lobes leads to problems with recognition of visual stimuli
Areas of temporal lobe involved in identification of visual stimuli
Fusiform face area: underside of temporal lobe, critical for recognizing faces. Damage results in prosopagnosia
Parahippocampal place area: responds to locations
Regions of the brain that encode words
Posterior parietal cortex, parts of the temporal lobe, regions of the prefrontal cortex. Together, form the semantic system. Occupies a significant portion of the brain, especially compared to other primates. May explain humans’ unique ability for language
Studies using _____ found more extensive activation in ___________ in response to ______, but when presented in a ________ or ________, _______ were activated.
fMRI, left hemisphere, words, narrative, other context, both hemispheres
Additional areas of brain involved in processing written language
Visual word form area in fusiform gyrus recognizes written language, a fact that is consistent across speakers of different languages
Areas of brain involved in processing numbers
Parietal cortex with input from occipitotemporal cortex, a region that participates in visual recognition and reading
Patient Tan
Louis Victor Leborgne, could only say “tan”. Pierre Paul Broca learned that he could understand speech but could only say “tan”. After Leborgne died, Broca performed autopsy and found large lesion in a part of frontal lobe (Broca’s area), which is now known to be vital for speech production.
Broca’s aphasia
Non-fluent aphasia. Damage to left frontal lobe. Speech is slow and halting, but language can still be understood
Wernicke’s aphasia
Fluent aphasia. Damage to left temporal lobe. Difficulty in comprehending speech, but not in producing it
Pure word deafness
Damage to superior temporal lobes in both hemispheres. Unable to comprehend heard speech on any level, but are not deaf. Just cannot link sound of words to meaning. Can make perfect sense of written language.
