Parkinson's disease and Alzeimers disease Flashcards
Parkinsons disease is
a progressive disease of the nervous system marked by tremor, muscular rigidity, and slow, imprecise movement, chiefly affecting middle-aged and elderly people. It is associated with degeneration of the basal ganglia of the brain and a deficiency of the neurotransmitter dopamine
Alzeimers disease is
progressive mental deterioration that can occur in middle or old age, due to generalized degeneration of the brain. It is the commonest cause of premature senility.
Atrophy of the temporal lobe, hippocampus
Price et al 2000 modern techniques?
idea of neuropsyc, can’t have one without the other
Through CT, MRI, functional MRI, MRS, SPECT, and PET techniques based on computer science and isotopes, diseases of the cerebrum, formerly regarded as functional, were found to have visible structural and functional abnormalities. The foundation of the dichotomy between neurology and psychiatry was at least partially effaced
neurology and psychiatry should be together because
A secondary reason calling for further integration has been the increasing recognition that psychiatric symptoms are common and important contributions to morbidity in neurologic diseases and that many attributes of psychiatric diseases may in fact be neurologic in origin.21,2
3 main questions which need to be answered..
- How do biologic processes of the brain give rise to mental events?
- How do environmental factors modulate the biological structure of the brain?
- How can these forces be harnessed to promote mental health and recovery from brain injury?
Cortical release phenomena
Oroghi, 2015 –> disibition of neural structures.. VH hallucinations are caused by disinibited neurones
Disinibited neurones cause
cholinergic denervation of the visual associative cortex (Perry)
Pharcomology of manipulting cholinergic (acetylcholine)
increase, agonist –> more VH
decrease inhibiter–> less VH
Meppelink, 2009
fMRI of PD showed decrease activation of visual associtive cortex in PD patients
Silverberg, 1995
PET Schizophrenia, showed acitvation of VAC… similar underlying mechanism involved
Howard
fMRI, show reduced resoponse the of occibital cortex, of exogenous visual stimuli, so this may disinhibt endogenous visual memories when they emerge in conciousness
VAC
place where you integrate information, inlufnce from topdown processing..
Price 1983,
area 19, VAC implicated in VH
CE of VH in PD–>
activation is inconsistent, can’t imply that is the cause, may just be impacted… but can start to understand maybe involved in the psychiatric phenomena that is VH
Bruer
dopamine agonsts relieve depprsive symptoms
PD patients with depression show…
decreased dopamine, showing decreased activation of cortical areas
Barone (2010)
PD deppresive symptoms were associated with decrease in volume of OFC and hippocampus
Lorenzetti
structrual abnormalties in MDD, in the OFC and hippocampus,
beruger
could explain why depression effects lots of aspects of cognition effecting lots of different frontal/ cortical regions…
Apathy
reduction in motivation, to make decisions, lack of energy
apthay and ICD are
two ends of a spectrum of dopamine levels
PD patients reduce DA = Czernecki, 2001
more apathy
PD patients with DA agonist =
less apathy
Lancot
SPECT AD, apathy symptoms felt, associated lower perfusion of the OFC and ACC (key decion making areas)
