What are major signs of dementia
- - progressive deterioration of cognitive (ie thought) function
- - most notably memory, but also attention language, and problem solving
- - neuropsychiatric symptoms- apathy, agitation, depression
- Women have the higher prevalence and this increases over 78
Why dementia is a burden to our society?
the cost 5 billion a yr but there are hiddeb costs
How does memory impairment manifests in dementia?
- - difficulty learning o retaining new information
- - information retrival deficits
- - ersonal episodice memory impairement (misplacing items
- -declarative memory (what) affected more than procedural memory (how)
How language deficit is expressed in dmentia?
- - list generation deficits
- -word finding difficulties (naming problems)
- - less complex sentence structure (but comprehension reasonable intact
How the deficit of executive function is expressed in dementia
-problems in planning, predicting, correlating, abstracting
- problems in integrating and processing of information in order to make a decision (often the first sign in highly intelligent people)
Which behavioural and emotional changes occur in dementia?
- - these changes are very common and are often the main treatment focus as they trigger institutionalisation
- - apathetic, socially withdrawn, depressed
- - disinhibition (inappropriate sexual behaviour orlanguage)
- - self centered behaviours (childishness, selfishness)
- -agitation, wandering, agresion
- - sleep disturbances
- - delusions, perceptual disturbances
What is the cause of dementia?
- - results from impaired functioning of cortical andsub-cortical brain systems, particularly those associated with memory and other cognitive functions
- - generally caused by structural damage that is progressive and relatively irreversible
What is the most common cause of dementia is?>
Alzheimer's disease even under 65 (35%) and this increases to 54% over 65
What is the gross neuropathology of alzheimers?
- - shrinkage of the brain is easily detected by eye. Evident from opening up of sulci and apparent enlargement of ventricles
What are microscopic neuropathology of alzheimers
- - amyloid plaques (aka seni,e plaques, neuritic plaques) extracellular deposists of an abnormal, insoluble protein call amyloid
- - neurofibrillary tangles- intracellular collections a protein called tau, from disrupted neuronal microtubules
- - widespread loss of neurons
- these changes typically first appear in the temporal lobe (entorhinal cortex and hippocampus), but then spread to prefrontal cortex and beyond
What are neurofibrillary triangles?
How does alzheimer's spread through the brain?
- Starts in the prefrontal cortex then develops to the temoral cortex and bottom of midbrain and occitpial lobe then severe AD results in majority of the brain
The lobes of the cerebral cortex
Where is the hippocampus is located?
- - deep into the temporal lobe
What are the different types of amnesia?
- retrograde amnesia- loss of memory before the incident
- anterograde amnesia- loss of memory ofter incident
Memory and learning definitions
- - learning is the acquition of new knowledge or info
- - memory- the retention of learned info
- - declarative memory- memory for facts and events - easy to form and easy to forget, can be recalled for conscious recollection
- - procedural memory- memory for skills and behaviour - hard to learns, requires repitition, hard to forget, can be recalled without conscious recollection
What is declarative memory?
- - immediate memory (fractionsof seconds)
- - limited capacity
- - requires continuous rehearsal
- - use and lose
- Working memory (sec-min) - a more elaborate form of short term memory- perhaps a reflection of multiple short term memory systems
- Long term memory (days to years)- unlimited capacity, doesnt require continuous rehearsal, use or lose
memory formation and storage
- - hippocampus is critical to forming declarative memories
- - the memories are stored ealsewhere- in association cortex
So in an alzheimers pt they have wasting of the hippocampus
- - prefontal lobe wasting- loss of speech/ language, function, behavious and emotional state
- - wasting of hippocampus- wasting of memory
Where and what does the orbitofrontal cortex?
Dorsolateral prefrontal cortex