8 Memory, Time and Prediction Flashcards
What is the Episodic memory?
The what, where and when of memory.
Time estimations made my H.M? & Order Judgments in Amensia.
Time intervals were normal for H.M for intervals under 20 seconds.
Patients with hippocampal lesions effects their ability to narrate events in the order they occurred. Suggesting hippocampus has a role in time and the process of events.
How is the hippocampus involved in Time Cells? Study with rats and a treadmill.
Rats had to spend a certain amount of time on the treadmill. Cells in the hippocampus were recorded. Turns out that there were cells that seemed to code for the amount of time animals spent on the treadmill.
If you have to do something for a particular amount of time, there will be a particular group of cells that fire.
This shows that time cells are not to do with DISTANCE TRAVELLED. Doesn’t matter if the treadmill is moving fast or slow.
What is the Scalar Expectancy Theory (SET)
The scalar timing or scalar expectancy theory (SET) is a model of the processes that govern behaviour controlled by time. The model posits an internal clock, and particular memory and decision processes. SET is one of the most important models of animal timing behaviour.
When asking to time an event a mechanism turns on, and then some part of the nervous system will start accumulating. Then compared to events of similar duration.
An internal pacemaker depends on the oscillations of the nervous system (beta and gamma frequencies).
Effects of THC on time perception?
THC is consistent to increase time pacemaker speed. e.g. Makes things go faster
Time estimation during life-threatening situations>
time slow down in life threatening situations. Post-fall people think they were hanging up top for longer.
However, the freefall was consistent with control.
What is Chronostasis?
When staring at the cross and then moving to the clock, the speed the clock moves speeds up.
During Sccade (Rapid eye movement) - The visual system suppresses input. Eyes move rapidly but the visual system doesn’t pass information into higher order systems.
Upon fixation - the nervous system fills in the gap retrospectively.
What is the Flash lag illusion?
Thinking one square is bigger than the other. They are the same but the nervous system is location squares forward in time - i.e where they will be rather than where they are.
When you recall a memory are you reactivating the network that was involved in encoding it? Why.
Yes, there is some activity. But it is in a higher order area. You will reactivate at least some of the areas of the brain responsible. However, this is not 1-1.
Why might this be?
- Maybe remember the detail of how things fit into your perception?
- Reconsolidation is the idea when you encode information, information is stored in an active state (neurons firing)
- When you reactivate a memory you turn the memories back on where it is labile and more prone to change
Why do some memories endure? (9/11 terrorist attack study)
Memories related to trauma or high excitment are likely to endure.
Study showed that people closer to the incident remembered it more vividly and had more emotional attachment.
What can CNS stimulants do to memory? (Humans similar compounds are adrenaline and corisol).
Enhance memory. Studyes shown that administering low doses of CNS stimulates chances memory.
Similar compounds Humans similar compounds are adrenaline and corisol.
What does Adrenaline do?
Is a hormone and a neurotransmitter.
- produced in adrenal gland. (some in brain)
- Fight or flight.
- Increase heart rate and blood flow
- Raised blood sugar
- Increased strength and physical performance
What does cortisol do?
- Steroid hormone
- Involved in hydrocortisone
- Produced by stress
- Readily crosses the blood brain barrier
- produces a slower response to stress
What is memory for? (EFT)
Episodic Future Thinking (EFT)
Imagining or stimulating a specific epuside that might occur in ones personal future.
How does medial temporal lobe damage effect episodic future thinking (EFT)
Medial temporal lobe damage effects planning and details of imagination of future scenarios.
What do the place cells tell us about the rat that moved through the maze?
The rat mapped out the run back to base through a neural pattern in its head. The hippocampus it allows it to predict it forward in space about its route.
Hippocampus allows for prediction.
