Psych 2NF3 C01 Dr. Khan 2014-01-14
Auditory representation is what you hear, and speech is organized to say what you want to say
(connected Wernicke’s and Broca’s Area)
- Start off with auditory information that travels to temporal lobes from ears. Sound
processing occurs in this auditory area. Sounds are processed into auditory
representations in the temporal lobe. They are moved along the arcuate fasciculus. It
arcs around the lateral fissure. This pathway leads to Broca’s Area. In Broca’s Area,
sound representations are converted into speech movements. These representations
are sent to muscles that lead to movements.
Clinical neuroscience – look at brain and map it onto symptoms that occur
- Wernicke’s aphasia – disruption in the superior temporal gyrus. If temporal lobe is
damaged, speech movements can still occur, however speech will be disorganized.
Patient tries to communicate ideas but words don’t come out in correct order. Listener
will not understand this. Thoughts cannot be articulated through written work because of
- Example: the patient was able to repeat what the therapist was saying, this
means that Wernicke’s area is not completely damaged.
- Broca’s aphasia – disruption in inferior frontal gyrus. If frontal lobe is damaged, will
have organized speech, however speech movements will be disrupted. Thoughts can be
articulated through written work because only speech movements are disrupted.
The Brain Mappers:
- Korbinian Brodmann (1868 – 1918)
- Mapped what part of brain does what – idea of localized function
- Karl Lashley (1890-1958) & Shepard Franz (1874 – 1933)
- Specific location (engram) for specific memories?
- An engram is a representation of specific memories
- Engram of memory is distributed in different parts of brain (ie. Visual
component, auditory component, olfactory component)
- Law of Equipotentiality
- When you think about rats in mazes, memory becomes important. Based
on cortical lesion studies, memory is actually equally distributed
- Went away from localist perspective, instead looked at distribution
- Law of Mass Action
- The extent of behaviour disturbance depends on how large the injury is. If
there is a smaller lesion, there will be a smaller disturbance in behaviour
Wilder Penfield (1891 – 1976)
- There are no pain receptors on skull. Use local anesthetics to skin around skull. Can
activate (produce small electrical currents) different parts of the brain and can have
awake subjects to understand brain function and clinical consequence.
1 Psych 2NF3 C01 Dr. Khan 2014-01-14
Wernicke’s Idea of Disconnection
- Different regions of the brain have different functions BUT, there is interdependence!
There is interaction!
- In order for function of speech to occur, need organization and appropriate sequence of