Alzeimers disease and anphantasia Flashcards
(24 cards)
what is a neurodegenerative disease
diseases characterised by the progressive loss of neurons in the brain (initially in the hippocampus)
alzheimers disease
a neurodegenerative disease that is characterised by the gradual widespread degeneration of brain neurons, progressively causing memory decline
symptoms of alzheimers disease
decrease in cognitive functions (e.g ability to plan/problem solve), personality changes, changes in mood/emotion, frequently becoming confused or disorientated, difficulty with language/communication
how can alzehimers be diagnosed
through a post-mortem examination, where leisons can be examined through neuroimaging
leisons
an area of brain tissue that has been damaged due to disease or injury
what are the two primary leisons associated with alzheimers disease
they are predominatley identified in the hippocampus, are amyloid plagues and neurofilliary tangles
amyloid plagues
fragments of the protein beta-amyloid that accumulates into insoluble plagues that inhibit communication between neurons
neurofibrillary tangles
an accumulation of the protein tau that forms insoluble tangles within neurons, which inhibit the transportation of essential substances and eventually kills the neuron entirely
what does an mri scan of an alzheimers brain look like in comparison to a healthy brian
a lot more blank space which indicates a loss of brain mass
how does alzheimers affect episodic and semantic memory
as damage can be associated with the hippocampus, people with alzheimers disease may struggle to remeber semantic and episodic memories, this also means that they lack the capacity to draw on episodic and semantic memories in order to plan and construct new future scenarios
aphantasia
a phenomenon in which individuals lack the capacity to generate mental imagery
mental imagery
the visual representations and experiences of sensory information without the presence of sensory stimuli, can vary in details and vividness, during creation individuals draw on episodic and semantic memories to recreate perceptual experiences
aphantasia degree of mental imagery
describe themselves as not having the power to generate mental imagery altogether
cause of aphantasia
no known cause, individuals can be born with it or suddenly acquire it during life
duration of sensory memory
0.2 - 4 secs
duration and capacity of iconic memory
unlimitede capacity, duration of 0.3-0.4 s
duration and capacity of echoic memory
capacity is unlimited, duration is 3-4 secs
how does auditory/visual info go into hearing or the visual sensory register
in its original sensory form
why do people with aphantasia struggle to retrieve autobiographical events and construct possible imagined futures
it is difficult for them to retrieve personal experiences as they cannot generate vivid mental imagery of past autobiographical events, they are able to apply non-visual components of the autobiographical memories to future events, but the lack of mental imagery makes this process more difficult
how is sensory memory lost
due to a lack of attention to the stimuli
how is long term memory lost
memories can become lost over time
haptic memory
info specific to physical touch, belived to have a duration less than 2s
why is elaborative rehearsal more effective in transferring info from STM to LTM
because we are elaborating and adding detail to info which allows us to understand things better
after info has been encoded into LTM, what happens
further processes into different types of LTM and organised in different parts of the brain
