1. Chapter 19 Amanda Salcido
Memory
Chapter 19
Amanda Salcido

2. William Scoville Conducted an operation on HM Problem with HM
Experienced epileptic seizures cense the age of ten
By the age of 29 epileptic seizures become more severe and more frequent
Operation removed parts of
the temporal lobes
Hippocampus
Amygdale
Adjacent areas of the cerebral cortex
Conducted an operation on HM
Problem with HM
Experienced epileptic seizures cense the age of ten
Believed to from being knocked unconscious from a bicycle wreck
By the age of 29 epileptic seizures become more severe and more frequent
Originally the seizures where no more then ten times a day but were very light
After time they had become much more severe and included tong biting, loss of consciousness
Operation removed parts of
the temporal lobes
Hippocampus
Amygdale
Adjacent areas of the cerebral cortex

3. Results of HM surgery Less severe and infrequent seizures
Improved intellectual ability
Anterograde amnesia
No longer recognize
hospital staff
Could no longer find
his way around
Partial retrograde amnesia
Less severe and infrequent seizures
Improved intellectual ability
Most likely do to him not being so tiered any more
Anterograde amnesia
He was no longer able to form new memories, a lot like Lucy on 50 first dates
Do the same puzzles and read the same books with no recollection of doing them previously
Could not remember if he ate 30 min before hand
No longer recognize hospital staff
Could no longer find his way around
Retrograde amnesia
He was unable to remember any of the events that occurred while he was in the hospital before the surgery or that his uncle had died three year before

4. What was derived from HM and others
There is a relationship between the amount of hippocampus and hippocampus gyrus is removed to the amount of memory less
The hippocampus is important for storing new memories
Memories are not stored in the hippocampus
Other brain structures are involved
There is a relationship between the amount of hippocampus and hippocampus gyrus is removed to the amount of memory less
The hippocampus is important for storing new memories
Memories are not stored in the hippocampus
Other brain structures are involved

5. Memory Long-term Short-term Implicit Procedural Explicit Episodic
Semantic
Topographic
Long-term memory- Memory that has no capacity limits and lasts from minutes to an entire lifetime
ie: your memory of your family vacations or your home phone number
Short-term memory- Memory that has limited capacity and that lasts only about 20– 30 seconds in the absence of attending to its content
ie: plus or minus 7…phone numbers
Implicit memory is a type of memory in which previous experiences aid in the performance of a task without conscious awareness of these previous experiences (Schacter, 1987). Evidence for implicit memory arises in priming
ie:
procedural memory Memory for actions, skills, and operations
ie: how to tie your shoes
explicit memory conscious and intentional recollection of information ; specific event that has occurred at a specific time and place
ie: Remembering a specific driving lesson is an example of explicit memory, while improving your driving skills during the lesson is an example of implicit memory.
episodic memory Memory of specific events, including when and where they occurred
semantic memory Memory of general knowledge not associated with a particular context; For instance, you can answer a question like "Are wrenches pets or tools?" without remembering any specific event in which you learned that wrenches are tools.

6. Topographic memory
John O’Keefe- recorded the activity of nerve cells in the hippocampus of rats as they moved around an enclosure
Humans and monkeys- lesions in the posterior parietal cortex causes problems with orientating our selves in space
John O’Keefe- recorded the activity of nerve cells in the hippocampus of rats as they moved around an enclosure
Findings- some cells fired because of what the rat was doing while other fired depending on where the rat was in the enclosure
place cells- represents a cognitive map of environmental spaces
Humans and monkeys- lesions in the posterior parietal cortex causes problems with orientation our selves in space
right hippocampus and parietal lobe- has an increased amount of blood flow for individuals recalling a sequence of locations in an environment
- an experiment was done on England taxi drives
- computer game where participants played in a town for an hour and then were asked to get to a location, they would block roads and lock doors to make participants use there topographic memory

7. Short-term memory in the brain
is necessary to move
information into long
term memory
Prefrontal cortex-
part of the frontal lobe
that lies in front of the
area concerned with
movement and speech
Short-term memory is necessary to move information into long term memory
-short term memory allows us to compare in coming information to information already received
ie: so an individual can decided quickly if the power point slide is an extension of the last slide or of separate information
-individuals with an impaired short-term memory of one kind can use tricks to get information into long term memory
ie: individuals who have a hard time with phonological information will not be able to remember spoken words by the way they sound but can remember then by there meaning. So if I was to tell a said individual that I will be having dinner at McDonalds for Thanks giving, they will not be able to remember it as McDonalds but as the golden arch of fast food.
Prefrontal cortex- part of the frontal lobe that lies in front of the area concerned with movement and speech
- hold information that is for immediate use like the pizza huts phone number

8. University of California
Joaquin Fuster and colleagues
experiment on monkeys remembering the location of hidden objects
end result
prefrontal cortex contains separate processing mechanisms for remembering ‘what’ and ‘where’ an object is
University of California, Joaquin Fuster and colleagues
- experiment on monkeys remembering the location of hidden objects,
- using delayed response tasks to test short-term memory
- different cells fire in the prefrontal cortex depending on the position of the hidden object – as if I t was a map and also used parts of the parietal and temporal cortex
- end result
- prefrontal cortex contains separate processing mechanisms for remembering ‘what’ and ‘where’ an object is

9. How memory works Depends on specific changes in synaptic effectiveness
First experiment was in the 1970s
a marine snail Aplysia californica
Depends on specific changes in synaptic effectiveness
First experiment was in the 1970s
a marine snail Aplysia californica
Strengthened and weakened its defensive reflexes for withdrawing its tail, respiratory gill and its spout

10. Experiment results Touching the siphon causes withdrawal of the gill
Repeated touches
Habituation
Decrease in the amount of transmitters released by sensory cells at there synapses with motor cells
Touching the siphon causes withdrawal of the gill
Repeated touches
Habituation
Decrease in the amount of transmitters released by sensory cells at there synapses with motor cells

11. Results continued
Noxious stimuli applied to the head or tail + a harmless stimuli applied to the siphon
Sensitization
Modification of the number of synapses in the neural circuit
Also, found that learning is not done by separate ‘memory cells’
Noxious stimuli applied to the head or tail + a harmless stimuli applied to the siphon
Sensitization
Modification of the number of synapses in the neural circuit
These changes can last as long as few minutes or several weeks depending on the amount of training
Also, found that learning is not done by separate ‘memory cells’
Instead by the cells engaged in the task with which the learning is concerned

12. Latter findings Tim Bliss and Terje Lomo
Short, rapid bursts of stimuli of nerve fibers that formed synapses with dendrites in the hippocampus increases the efficacy of those synapses
The nerve fibers form one of the main inputs from the cerebral cortex to the hippocampus – thus causing long-term potentiation for memory
Potentiation- increased effectiveness of synapses caused by protein synthesis
Tim Bliss and Terje Lomo
Short, rapid bursts of stimuli of nerve fibers that formed synapses with dendrites in the hippocampus increases the efficacy of those synapses
The nerve fibers form one of the main inputs from the cerebral cortex to the hippocampus – thus causing long-term potentiation for memory
Potentiation- increased effectiveness of synapses

13. When we encounter stimuli
Two things can happen
If the stimuli does not involve the synthesis of new protein
Then the results will slowly and spontaneously reverse
If the stimuli does require the synthesis of new protein
Then if will result in a more permanent change in the receptors
Two things can happen
If the stimuli does not involve the synthesis of new protein
Then the results will slowly and spontaneously reverse
Ie: when the hippocampus receives a single short bursts of shock for one second
If the stimuli does require the synthesis of new protein
Then if will result in a more permanent change in the receptors
Ie: when the hippocampus receives several bursts of shock in rapid succession

14. How does the protein get the right synapses
It doesn’t
At least not all of the time
Instead it binds to any synapse in the post-synaptic cell that has been recently active
It doesn’t
At least not all of the time
Instead it binds to any synapse in the post-synaptic cell that has been recently active

15. Hippocampus
Depends on the synthesis of new protein for lasting change on memory
hippocampus of a mouse
Research- Knocked out the gene for a subunit of the NMDA receptor
Results:
These mice had difficulties in learning to finding a submerged platform
Research- injected with a protein synthesis inhibitor
results:
Only able to remember the correct path for 3hrs