Lecture 18 Flashcards
what is Aphasia
refers to a disturbance in understanding, repeating, or producing meaningful speech.
• The difficulty must not be caused by simple sensory or motor deficits or by lack of motivation.
• The deficit must be relatively isolated, such that the patient must be capable of recognizing when others are attempting to communicate. The patient must be somewhat aware of what is happening around them
Neurons in the posterior language area seem to be responsible what
word comprehension.
Neurons in the posterior language area seem to be responsible for word comprehension.
Neurons here probably activate what
the ensemble of neurons throughout sensory association cortex that store the representations (the meanings) of specific words. For example, activating the DOG neurons here would cause activity throughout sensory association cortices (vision, hearing, touch, smell, taste, and even motor commands like petting) that are associated with the word DOG.
What if there is damage to the posterior language area – the region responsible for language comprehension - that is located in the posterior part of lateral fissure, near the junction of the temporal, occipital, and parietal lobes.
Transcortical Sensory Aphasia
What is Transcortical Sensory Aphasia
Failure to comprehend the meaning of words and an inability to express thoughts with meaningful speech.
• Word perception (recognition, identification) is fine, including: – Word repetition (e.g., repeat after me…)
– Reading (e.g., read out loud…)
– Writing (e.g., write the words you hear…)
However, in all cases, you won’t actually understand the words you are saying, reading, or writing
what is Wernicke’s area
involved in analysis of speech sounds and in recognition of spoken words. Region of auditory association cortex on left temporal lobe of humans.
aka it is the dictionary of the brain… you hear something and it brings everything related so you know what it is
Being able to hear is where
primary auditory cortex
is hearing, recognizing words and comprehending them all different or the same
Being able to hear is one thing (primary auditory cortex);
– Recognizing words is another thing (Wernicke’s Area);
– Comprehending them—understanding their meaning—is yet another thing (Posterior Language Area).
what is the result of damage just to Wernicke’s area
PURE WORD DEAFNESS
what is PURE WORD DEAFNESS
Pure word deafness is a disorder of auditory word recognition, an inability to comprehend or repeat spoken words.
“I can hear you, but I don’t recognize the words you are saying. I even have trouble repeating what you say.”
It is caused by damage to Wernicke’s area or disruption of auditory input to this region
People with Pure Word Deafness can:
Hear just fine.
• Interpret non-speech sounds (doorbell, phone, barking).
• Read and write.
• Read lips.
• Speak intelligently, but they can’t recognize the words they are saying by listening to themselves. Over time their speech becomes a bit awkward, like when a deaf person speaks.
whats WERNICKE’S APHASIA
the result of damage to both Wernicke’s area and the Posterior language area, which means you have features of transcortical sensory aphasia and pure word deafness
what is the difference between TRANSCORTICAL SENSORY APHASIA VERSUS WERNICKE’S APHASIA
Patients with transcortical sensory aphasia have trouble with language comprehension, but they can repeat what other people say to them; they can recognize spoken words.
• Patients with Wernicke’s aphasia have trouble with language comprehension and are generally not capable of repeating what other people say to them.
• Both of these aphasias involve deficits in language comprehension, so the textbook says both involve damage to
the posterior language area. However, most researchers would say the posterior language area is Wernicke’s area, in which case pure word deafness and transcortical sensory aphasia reflect damage in different parts of Wernicke’s area
The defining feature of Wernicke’s aphasia (and transcortical sensory aphasia) is what
poor language comprehension
These people can have fluent speech production, but what they say is meaningless and typically filled with function words
what are function words
such as a, the, in, about (as opposed to content words that convey meaning, such as nouns, verbs, and adjectives).
Their speech seems natural and is filled with intonation and emphasis (prosody). Words seem to come easy to them, but do they make sense (Wernicke’s aphasia)
no
what is receptive aphasia
The defining feature of Wernicke’s aphasia (and transcortical sensory aphasia) is poor language comprehension. These people can have fluent speech production, but what they say is meaningless and typically filled with function words, such as a, the, in, about (as opposed to content words that convey meaning, such as nouns, verbs, and adjectives).
• Their speech seems natural and is filled with intonation and emphasis (prosody). Words seem to come easy to them, but unfortunately what they say is meaningless.
• This disorder has been characterized as a receptive aphasia, because the people have no trouble coming up with nonsense things to say; it is just that words have no meaning to them.
what is CONDUCTION APHASIA
the result of damage to the connection between Wernicke’s area and Broca’s area known as the arcuate fasciculus
characterized by inability to repeat words that are heard. The ability to comprehend speech and speak normally is fine.
It is caused by damage to and around the arcuate fasciculus, a bundle of axons that connects Wernicke’s area with Broca’s area.
Characterized by an inability to repeat the exact words you hear. Other than that, you are fine, that is you have meaningful, fluid speech and good speech comprehension.
• When asked to repeat the word ‘house’, the person may say “home”.
• When asked to repeat a nonsense word like ‘blaynge’, the person will be unable to do it. They will just say I didn’t hear you.
AKA they hear something, they have to go into their brain and see what the definition is/wha it is associated with, and then they will say the word back.. not necessarily ‘repeating’ because they cannot repeat words that are not real and the example of house/home
what are DISORDERS OF READING
PURE ALEXIA
what is PURE ALEXIA
Damagetothevisualword-formarea(VWFA) disrupts the ability to perceive written words
People with this damage (Pure Alexia o rPure Word Blindness) cannot read,, why
they cannot recognize written words. However, they can write just fine. They just can’t read what they write.
what does Reading involve
Reading involves at least two different processes: direct recognition of the word as a whole and sounding it out letter by letter
what is Whole- word reading
Reading by recognizing a word as a whole; “sight reading
what is Phonetic reading
Reading by decoding the phonetic significance of letter strings; “sound reading
Fusiform face area of right hemisphere has ability to quickly recognize unique configurations of people’s eyes, noses, lips, and other features of their faces even when differences between two people’s faces are very similar
• For example, parents and close friends of identical twins can see at a glance which twin they are looking at
• Similarly, VWFA of left hemisphere can do what
recognize word even if it closely resembles another one
such as the small difference between car and ear
define Dyslexia
means “faulty reading”