Lecture 13 Memory 2.0 Flashcards
SLUMS Exam
Saint Louis University Mental Status Exam
- It is designed to identify individuals with mild or early dementia through measuring orientation, memory, attention, and executive functions.
- It takes about 7 minutes to complete.
Day of the week
Year
Province
- Please remember these five objects. I will ask you what they are later.
- You have $100 and you go to the store and buy a dozen apples for $3 and a tricycle for $20. How much did you spend? How much do you have left?
- name as many animals as you can in one minute. Write them down and then count them up.
- What were the five objects I asked you to remember?
- 1 point for each one correct.
- I am going to give you a series of numbers and I would like you to give them to me backwards. For example, if I say 42, you would say 24. 87 648 8537
- Story remembering
Name 3 things that affect encoding/storage/retrieval
- The amount of attention given to new stimuli can diminish the amount of information that becomes encoded for storage.
- Physical Damage.
- Decay: natural over lifetime, too much=dementia
What is the difference between Amnesia and Dementia?
- Amnesia - a partial or total loss of memory.
- Dementia- a chronic or persistent disorder of the mental processes caused by brain disease or injury and marked by memory disorders, personality changes, and impaired reasoning. (rarer than amnesia?
What is infantile Amnesia?
Infantile Amnesia:
- No episodic memories of events before 2 years of age (typically).
- We do have implicit memories eg. being able to walk.
- (are there any exceptions documented)
Theories of Infantile Amnesia
- IA is due to an inability of the immature nervous system to store episodic info.
- Related to language development and tight relationship between consciousness and language.
^^those 2 (development of the brain itself. While young children and even infants appear able to recall information for weeks or months, linking those memories to verbal cues is more difficult).
•Theory of encoding: that at that age we do not know what is important and so we don’t encode it (attention) not putting a semantic marker on things, cause everything is new, eg., going to the hospital as 2 yr old getting new sister…might be a normal everyday thing
Though children can be prompted to recall early memories, this recall is often plagued by problems with false memory caused by leading questions and unintentional cueing on the part of adults.
Describe 3 types of Amnesia
Retrograde amnesia:
•Disrupts memory for events that occurred before the trauma.
Anterograde amnesia:
•Disrupts memory for events that occurred after the trauma. (usually more complicated, remember some things not all,
Transient global amnesia:
•When people have no knowledge of their previous life but have intact skills and language.
Patient HM:
Name
When he was studied
Childhood disorder
- Henry Gustav Molaison, known to the world as ‘Patient HM’.
- He was studied for more than 50 years – from age 27 to his death aged 82.
- As a child, Henry suffered from epilepsy which became increasingly severe.
Name of HM’s surgery
Areas of brain removed
- HM underwent major and experimental surgery; a bilateral medial temporal lobe resection.
- This involved removing a portion of Henry’s temporal lobe, including parts of the hippocampus and amygdala, from both sides of the brain.
Effects of HM’s surgery
- Post-surgery HM had no more seizures but suffered from severe amnesia.
- Could remember his childhood but struggled to remember events from the few years leading up to the surgery and could not remember some things that had happened up to 11 years before.
- Henry also had severe anterograde amnesia; he had lost the ability to form new memories. Later, he would describe his condition as “like waking from a dream… every day is alone in itself”.
HM was important to neuroscience because…
- At the time of HM’s operation, it was thought that memory functions were spread throughout the brain.
- The fact that HM suffered one kind of amnesia so acutely as a result of damage to one part of his brain, and yet retained his intellectual abilities showed us that the temporal lobe is vital for memory function.
- The hippocampus is now known to be particularly important for long-term memory.
•
Describe Anterograde Amnesia
(and how it affects implicit/explicit memory differently)
- Normal implicit memory, problems in explicit memory.
- Impairment of declarative memory that affects both episodic and semantic memory operations.
- Inability to learn new facts and episodes.
- Intact ability to retain small amounts of information over short time scales (up to 30 seconds) but are dramatically impaired in their ability to form longer-term memories.
- This is interpreted as showing that the short-term store is spared from amnesia; indicates that it is localized elsewhere, not necessarily the hippocampus
- HM would have needed a caregiver, wouldn’t know what he was doing, what his purpose was
Retrograde Amnesia
is a loss of memory-access to events that occurred, or information that was learned, before an injury or the onset of a disease.[1] It tends to negatively affect episodic, autobiographical, and declarative memory while usually keeping procedural memory intact with no difficulty for learning new knowledge.
Motivated Forgetting
Motivated forgetting encompasses the term psychogenic amnesia which refers to the inability to remember past experiences of personal information, due to psychological factors rather than biological dysfunction or brain damage
•Usually caused by personal crisis Individual is orientated to time and place but not to identity. Either fails to recall identity or confabulates false identity.
Organic retrograde amnesia
- Caused by brain injury.
- Individual not orientated to time and place.
- Somewhere the mini-mental health exam would be helpful to indicate memory loss (what is name, date, etc).
Transient Global Amnesia
Transient global amnesia (TGA) is a temporary, anterograde amnesia with an acute onset that usually occurs in middle-aged and older individuals. It is often precipitated by particularly strenuous activity, high-stress events, or coitus, but it can be seen with migraines as well.
- Neurological disorder whose key defining characteristic is a temporary but almost total disruption of short-term memory with a range of problems accessing older memories.
- Sudden onset and no clearly identified cause; can sometimes be linked to migraines, epilepsy, cold showers, and stress hormones.
- Some imaging studies have indicated this type of amnesia to result from decreased metabolism and blood flow to the medial temporal lobes, which usually resolves spontaneously.
Patients with this condition are often described – wrongly – as being confused. It presents classically with an abrupt onset of severe anterograde amnesia. It is usually accompanied by repetitive questioning. The patient does not have any focal neurological symptoms. Patients remain alert, attentive, and cognition is not impaired. However, they are disoriented to time and place. Attacks usually last for 1–8 h but should be less than 24 h.
Memory in the Diencephalon
- Diencephalon – thalamus and hypothalamus.
- Dorsal medial nucleus of the thalamus and mammillary body of the hypothalamus appear to be particularly important in anterograde memory.
What types of dementia fit under the “Dementia” umbrella?
•The most common type of dementia is Alzheimer’s disease, which makes up 50% to 70% of cases.
Cortical vs. Subcortical Dementia
DSM-5 Dementia definition
Dementia is a general term for a decline in mental ability severe enough to interfere with daily life.
DSM-5 diagnostic criteria
6 Neurocognitive domains
5 things to expect in late-stage dementia
Alzheimer’s signs of onset,
the co-occurrence of other deficits,
generally lead to ______lobe dysfunction such as _____and _________
What types of memory usually remain unaffected for most of the disease’s duration?
- Alzheimer’s disease – accounts for 50% of the diagnoses of dementia.
- Onset: usually marked by initial memory problems, disorientation in familiar surroundings, and changes to personality and mood.
- There is also often a co-occurrence of other deficits, eg., Aphasia, agnosia and apraxia.
- Characterised by a progressive loss of function over a period of years, most notably in memory function. New explicit learning is impaired and the loss of recent memories is usually noticed first.
- Generally leads to parietal lobe dysfunction such as dyspraxia and agnosia.
- Short term memory, working memory and implicit memory seem to remain relatively unaffected until the disease is quite advanced.
- Most people live for five to fifteen years from the time of diagnosis until their death.
What Goes On In The Brain (AD)?
- General atrophy of the brain, especially in the temporal and association cortices.
- Increased size of ventricles.
- Loss of medium and large cholinergic neurons.
- Large numbers of amyloid plaques (an accumulation of beta-amyloid protein) and neurofibrillary tangles can be observed. (won’t be asked specifics on the exam)
- Severity of disease is correlated with the number of neurofibrillary tangles which are characteristic of dead or dying neurons.
- Excessive synaptic pruning. (Some is normal).
Alcoholic Dementia: Korsakoffs syndrome
Korsakoff’s syndrome:
- Memory impairments following long term alcoholism, due to vitamin deficiency.
- Severe anterograde amnesia.
- Localization difficult because patients show damage to many brain regions.
- Medial thalamus and mammillary bodies seem to be implicated.
