Memory, Learning & Amnesia Flashcards
What is Alzheimer’s disease?
the most common form of dementia in the elderly. It’s three defining characteristics are: neurofibrillary tangles, amyloid plaques, and neuron loss
What is amnesia?
any pathological loss of memory
What is the amygdala?
A structure in the anterior temporal lobe, just anterior to the hippocampus; plays a role in emotion
What is anterograde amnesia?
loss of memory for events occurring after the amnesia-inducing brain injury
What is the basal forebrain?
a midline area of the forebrain, which is located just in front of and above the hypothalamus and it is the brain’s main source of acetylcholine
What is bilateral medial temporal lobectomy?
the removal of the medial portions of both temporal lobes, including the hippocampus, the amygdala and the adjacent cortex
What is a CA1 subfield?
a region of the hippocampus that is commonly damaged by cerebral ischemia
What is a cerebellum?
a metencephalic structure that is thought to participate in the storage of memories of learned sensorimotor skills
What are concept cells?
cells, such as those found in the medial temporal lobe, that respond to ideas or concepts rather than to particulars. Also known as Jennifer Aniston neurons
What is a delayed nonmatching-to-sample test?
a test in which the subject is presented with an sample object and then, after a delay, is presented with a choice between the sample object and an unfamiliar object, where the correct choice is the unfamiliar object. The animal must remember the sample object so it can choose the other object
What are dendritic spines?
tiny protrusions of various shapes that are located on the surfaces of many dendrites
What is digit span?
the longest sequence of random digits that can be repeated correctly 50 percent of the time - most people have a digit span of 7
What is dual-trace theory?
the theory that memories are temporarily stored in the hippocampus until they can be transferred to a more stable cortical storage system. Also known as the standard consolidation theory
What is a electroconvulsive shock (ECS)?
an intense, brief, diffuse, seizure-inducing current administered to the brain via large electrodes attached to the scalp
What is an engram?
a change in the brain that stores a memory
What are engram cells?
neurons that maintain an engram
What is the entorhinal cortex?
an area of the medial temporal cortex that is a major source of neural signals to the hippocampus
What are episodic memories?
explicit memories for the particular events and experiences of one’s life
What are explicit memories?
conscious memories
What is global amnesia?
amnesia for information presented in all sensory modalities
What is global cerebral ischemia?
an interruption of blood supply to the entire brain
What is glutamate?
the most prevalent excitatory neurotransmitter in the CNS
What are grid cells?
entorhinal neurons that each have an extensive array of evenly spaced place fields, producing a pattern reminiscent of graph paper
What is the hippocampus?
a structure in the medial temporal lobes that plays a role in various forms of memory
What are implicit memories?
memories that are expressed by improved performance without conscious recall or recognition
What is the incomplete-pictures test?
a test of a memory measuring the improved ability to identify fragmented figures that have been previously observed
What is infantile amnesia?
the normal inability to recall events from early childhood
What is the inferotemporal cortex?
the cortex of the inferior temporal lobe, in which is located an area of secondary visual cortex
What are Jennifer Aniston neurons?
neurons, such as those found in the medial temporal lobe, that respond to ideas or concepts rather than to particulars. Also known as concept cells
What is Korsakoff’s syndrome?
a neuropsychological disorder that is common in alcoholics and whose primary symptoms include memory loss, sensory and motor dysfunction, and, in its advanced stages, severe dementia
What is learning?
the brain’s ability to change in response to experience
What is a lobectomy?
an operation in which a lobe, or major part of one, is removed from the brain
What is a lobotomy?
an operation in which a lobe, or major part of one, is separated from the rest of the brain by a large cut but is not removed
What is long-term depression (LTD)?
a long-lasting decrease in synaptic efficacy (the flip side of LTP) that occurs in response to prolonged low-frequency stimulation of presynaptic neurons
What is long-term memory?
memories for experiences that endues after the experiences are no longer the focus of attention
What is long-term potentiation (LTP)?
the enduring facilitation of synaptic transmission that occurs following activation of synapses by high-intensity, high-frequency stimulation of presynaptic neurons
What is medial diencephalic amnesia?
amnesia that is associated with damage to the medial diencephalon (e.g., Korsakoff’s amnesia)
What is the medial temporal cortex?
cortex in the medial temporal lobe that lies adjacent to the hippocampus and amygdala
What is medial temporal lobe amnesia?
amnesia associated with bilateral damage to the medial temporal lobes; its major features are anterograde and retrograde amnesia for explicit memories, with preserved intellectual functioning
What is the mediodorsal nuclei?
a pair of thalamic nuclei, damage to which is thought to be responsible for many of the memory deficits associated with Korsakoff’s syndrome
What is memory?
the brain’s ability to store and access the learned effects of experiences
What is memory consolidation?
the transfer of short-term memories to long-term storage
What is metaplasticity?
the modulation of long term potentiation (LTP) and/or long-term depression (LTD) induction by prior synaptic activity
What is the Morris water maze test?
a widely used test of spatial memory in which rats must learn to swim directly to a platform hidden just beneath the surface of a circular pool of murky water
What is a mumby box?
an apparatus that is used in the rat version of the delayed nonmatching-to-sample test
What is an NMDA receptor?
glutamate recptors that play key roles in the development of stroke-induced brain damage and long-term potentiation at glutaminergic synapses
What are nootropics?
drugs that purportedly improve memory
What are place cells?
neurons that respond only when the subject is in specific locations (i.e. in the place fields of the neurons)
What is posttraumatic amnesia (PTA)?
amnesia produced by a nonpenetrating head injury (a blow to the head that does not penetrate the skull)
What is the prefrontal cortex?
the areas of the frontal cortex that are anterior to the frontal motor areas
What is the pyramidal cell layer?
one of the major layers of cell bodies in the hippocampus
What is the radial arm maze test?
a widely used test of rats’ spatial ability in which the same arms are baited on each trial, and the rats must learn to visit only the baited arms once per trial
What is a reference memory?
memory for the general principles ad skills that are required to perform a task
What is a remote memory?
memory for experiences in the distant past
What are repetition priming tests?
tests of implicit memory; in one example, a list of words is presented, then fragments of the original words are presented and the subject is asked to complete them
What is retrograde amnesia?
loss of memory for events or information learned before the amnesia-inducing brain injury
What are semantic memories?
explicit memories for general facts or knowledge
What is standard consolidation theory?
the theory that memories are temporarily stored in the hippocampus until they can be transferred to a more stable cortical storage system. Also known as dual-trace theory
What is the striatum?
a structure of the basal ganglia that is the terminal of the dopaminergic nigrostriatal pathway
What are transcription factors?
intracellular proteins that bind to DNA and influence the operation of particular genes
What is short-term memory?
storage of information for brief periods of time while a person attends to it
What is transient global amnesia?
a sudden onset severe anterograde amnesia and moderate retrograde amnesia for explicit episodic memory that is transient - typically lasting only between 4 to 6 hours
What is working memory?
temporary memory that is necessary for the successful performance of a task on which one is currently working
What memory deficits did H.M. have following his bilateral medial temporal lobectomy?
Retrograde and anterograde amnesia; inability to form long-term memories
What did H.M.’s case contribute to knowledge on the neural basis of memory?
The medial temporal lobes play an especially important role in memory
The are different modes of storage for short-term, long-term and remote memory
An amnesic patient may have no recollection of a previous experience while demonstrating memory for it by previous experience
What are tests that assess implicit memory called?
Repetition priming tests
What are the two types of explicit long-term memories?
Semantic memories
Episodic memories
What type of memory do people with medial temporal lobe amnesia particularly struggle with?
Episodic memory
What is transient global amnesia caused by?
Stroke-induced damage to the CA1 subfield of the hippocampus
Which parts of the brain typically have lesions in Korsakoff’s patients?
Medial diencephalon (medial thalamus and medial hypothalamus)
Neocortex
Hippocampus
Cerebellum
Which neurotransmitter is severly reduced in Alzheimer’s patients and why?
Acetylcholine
This is caused by the degeneration of the basal forebrain
What is anmesia following a nonpenetrating blow to the head called?
Posttraumatic amnesia (PTA)
What are islands of memory?
Surviving memories for isolated events that occurred during periods for which other memories have been wiped out
What is Hebb’s theory of memory consolidation?
Memories of experiences are stored in the short term by neural activity reverberating (circulating) in closed circuits. These reverberating patterns of neural activity are susceptible to disruption - for example, by a blow to the head - but eventually they induce structural changes in the involved synapses, which provide stable long-term storage
______ deals with how experiences changes the brain
Learning
Any pathological loss to memory is called ______
Amnesia
_____ deals with how changes are stored and subsequently reactivated
Memory
H.M. learned an eye-blink _________ conditioning task
Pavlovian
_________ refers to translation of short-term memories into long-term memories
Memory consolidation
Conscious long-term memories are called ______ memories
Explicit
Tests that assess implicit memory are called _______
Repetition priming tests
_________ memories are explicit memories for general facts or information
Semantic
_______ is defined by its sudden onset in the absence of any obvious cause in otherwise normal adults
Transient global amnesia
________ is a disorder of memory common in people who have consumed large amounts of alcohol
Korsakoff’s syndrome
Amnesia following a nonpenetrating blow to the head is called _________
Posttraumatic amnesia
A _____ is a pathological state of unconsciousness
Coma
______ refer to surviving memories for isolated events that occurred during periods where other memories have been wiped out
Islands of memory
What effects does bilateral surgical removal of the medial temporal cortex have of performance on the delayed nonmatching-to-sample test?
Severe and permanent deficits
What effects does bilateral surgical removal of the hippocampus have of performance on the delayed nonmatching-to-sample test?
Modest deficits
What effects does bilateral surgical removal of the amygdala have of performance on the delayed nonmatching-to-sample test?
No effect
Why does ischemia-produced lesions to one small part of the hippocampus cause severe deficits in performance on the delayed nonmatching-to-sample test when the deficits associated with total removal of the hippocampus are only modest?
Damage to brain structures other than the hippocampus contributes to the amnesia observed in patients following global cerebral ischemia
What types of memory does the radial arm maze test assess?
Reference memory
Working memory
How does the radial arm maze assess reference memory?
The ability to visit only the baited arms of the radial arm maze
How does the radial arm maze assess working memory?
The ability to refrain from visiting an arm more than once in a given day
How do rats with hippocampal lesions perform on the radial arm maze?
Severe deficits in both reference memory (the visit arms regardless of baiting) and working memory (the visit arms multiple times per day)
Neurons that respond only when a subject is in specific locations are called what?
Place cells
What are head-direction cells?
Entorhinal cortex neurons that are tuned to the direction of head orientation
What are border cells?
Entorhinal cortex neurons that fire when individuals are near the borders of their immediate environement
Why would a patient’s particular Jennifer Aniston neuron fire for more than one concept?
There is an obvious relation between them or the patient thought the concepts were the same thing
What is the role of the inferotemporal cortex in memory?
It plays an important role in storing memories of visual input
What is the role of the amygdala in memory?
It is thought to play a special role in associating emotional significance to an experience
What is the role of the prefrontal cortex in memory?
Some regions of the prefrontal cortex seem to perform cognitive processes during working memory tasks, and other regions participate in other memory processes
What is the role of the cerebellum in memory?
It is thought to participate in the storage of memories of learned sensorimotor skills though its various neuroplastic mechanisms
What is the role of the striatum in memory?
It is thought to store memories for consistent relationships between stimuli and responses (habit formation)
The _______ is an apparatus that is used in the rat version of the delayed nonmatching-to-sample test
Mumby box
A _________ is a maze in which several arms radiate out from a central starting chamber
Radial arm
_______ refer to neurons that respond only when a subject is at specific locations
Place cells
______ refers to the memory for the general principles and skills that are required to perform a task
Reference memory
______ are entorhinal cells that each have an extensive array of evenly spaced place fields
Grid cells
The medial temporal cortex comprises the entorhinal, perirhinal and ________ cortices
Parahippocampal
______ is a method that uses genetic engineering techniques to insert the opsin gene, or varients of the opsin gene, into particular types of neurons
Optogenetics
Identification of an engram cell is a two-stage process involving the ________ and manipulate stages
Tagging
Patients with large prefrontal lesions often display anterograde and ________deficits in memory
Retrograde
Regions of the prefrontal cortex perform fundamental _______ processes during working memory tasks
Cognitive
True or False:
LTP cannot be elicited by low levels of stimulation that mimic normal neural activity
False
It can
True or False:
LTP effects are most prominent is structures that have been implicated in learning and memory, such as the hippocampus
True
True or False:
The hippocampus is not altered during learning
False
Learning can produce LTP-like changes in the hippocampus
True or False:
Mutant mice that display little hippocampal LTP have difficulty learning the Morris water maze
True
True or False:
Behavioural changes that appear to be memories can be induced in mice via LTP
True
True or False:
LTP occurs at specific synapses that have been shown to participate in the learning and memory in simple invetebrate nervous systems
True
Which receptor is prominant at the synapses at which LTP is commonly studied and what neurotransmitter does it bind?
NMDA receptor; Glutamate
What must be required for an NMDA receptor to activate?
Glutamate binding and postsynaptic neuron partial depolarisation
How do dendritic spines keep LTP events at one set of synapses on a postsynaptic neruon from affecting the other synapses on that neuron?
The calcium ions that enter a dendritic spine do not readily pass out of it, and thus they exert their effects locally
What structural changes to neurons does LTP cause?
Increases in numbers and sizes of synapses
Increases in numbers and sizes of postsynaptic dendritic spines
Changes in pre- and postsynaptic memanes
Changes in dendritic branching
What causes the structural changes of LTP?
Transcription factors
According to the reconsolidation notion, long-term memories are temporarily susceptible to posttraumatic amnesia when they are Select one: a. recalled. b. transferred to the cortex. c. transferred to the hippocampus. d. transferred to LTP. e. consolidated.
a. recalled.
A major contribution of H.M.’s case was the following: It
Select one:
a. was the first to strongly implicate the medial temporal lobes in memory.
b. effectively challenged the view that memorial functions are diffusely and equivalently distributed throughout the brain.
c. provided support for the view that there are distinct modes of short-term and long-term storage.
d. provided evidence of memory without conscious awareness.
e. all of the above
e. all of the above
Bilateral lesions of the medial temporal cortex that do not damage the hippocampus or amygdala produce
Select one:
a. slight object-recognition deficits in rats.
b. no object-recognition deficits in monkeys.
c. slight object-recognition deficits in monkeys.
d. major object recognition deficits in both rats and monkeys.
e. both A and C
d. major object recognition deficits in both rats and monkeys.
Electroconvulsive shock is commonly used in studies of memory because it
Select one:
a. improves semantic memory.
b. has amnesic effects similar to those produce by concussion.
c. causes hippocampal damage.
d. is an effective form of therapy for anxiety.
e. produces no retrograde effects on memory.
b. has amnesic effects similar to those produce by concussion.
In Alzheimer's disease, the brain damage is Select one: a. diffuse. b. restricted to the basal ganglia. c. restricted to the basal forebrain. d. unilateral. e. contralateral.
a. diffuse.
Memory for general principles and skills required to perform a task is called \_\_\_\_\_\_\_\_\_\_ memory. Select one: a. complex b. reference c. working d. place e. inclusive
b. reference
One major difference between the amnesia associated with advanced Korsakoff’s syndrome and that associated with bilateral medial temporal lobe damage is that patients with advanced Korsakoff’s syndrome have
Select one:
a. a retrograde amnesia that can extend back into childhood.
b. a mild retrograde amnesia for recent events.
c. deficits in consolidation.
d. anterograde amnesia.
e. difficulty forming new explicit long-term memories.
a. a retrograde amnesia that can extend back into childhood.
The cerebellum is thought to store memories of Select one: a. learned sensorimotor skills. b. faces. c. time. d. objects. e. spatial locations.
a. learned sensorimotor skills.
The induction of LTP at glutaminergic synapses appears to
Select one:
a. be a postsynaptic phenomenon.
b. be a presynaptic phenomenon.
c. depend on an influx of calcium ions into the postsynaptic neuron.
d. both B and C
e. both A and C
e. both A and C
Which structure is thought to store memories for visual images? Select one: a. amygdala b. inferotemporal cortex c. striatum d. prefrontal cortex e. cerebellum
b. inferotemporal cortex
