aging memories Flashcards
our first olfactory engrams
newborn babies of mothers who ate garlic during pregnancy do not show a typical garlic averison
our first auditory engram as a fetus
vibrotactile CS and loud noice US used to condition fetus in last two months of pregnancy - can get habituation to it or a pairing to another stimulus
can habituate to loud sounds at 22 weeks
respond with head twitches to recordings of father’s voice but prefer mothers’ voices - respond to a familiar or nonfamiliar sound
cannot discriminate between mother’s recorded voice and another person’s recorded voice and another person’s recorded voice at 36 weeks, but can detect mother’s live voice - different vibration and frequency in recording vs live
- perhaps not auditory aspect of mother’s voice
discriminate between temporal aspects of speech with no spectral components, and nonspeech sounds
first engram as a newborn
prefer mother’s voice over other voices (conditioning affect)
learn sucking pattern to produce distinct recorded voices - hook pacifier up generate certain sucking pattern to hear mother’s voice
discriminate between their native and foreign languages (2 days old)
higher frequency sucking when hearing foreign language
remember melodies presented in third trimester at least 1 month after birth
infants know more about fine differences of human sound of any language, but have preference toward certain ones - more than adults
autobiographical memories
explicit memory of events that occurred in a specific time and place in one’s personal past
childhood (infantile) amnesia
freud popularized the fact that most people have very few memories before age 4 - some people do remember but very likely - are we remembering o.g. event or recall event
childhood amnesia occurs cross-culturally, but memory structure differs by culture
what complimentary processes may account for the childhood amnesia
- vulnerability of early memories
young children do not form and/or consolidate memories like adults
- the strength of memory formation increases with age - Inaccessibility of early memories
young children form and consolidate memories, but retrieval is blocked - not adequate enough to access early memories
-there are emotional, cognitive and/or linguistic changes shift complexity of language) that alter retrieval
memories are acquired and retrieved differently in the first 4 years - structure of indicies is different
cognitive modularity
is the idea that the mind is made of interconnected modules that a domain-specific
developmental modularity
developmental stages may reflect the maturation of modules (and submodules), and maturation of their inter connections
the maturation of some modules may reflect neural maturation rates
hippocampal structure changes over the course of development
neurogenesis decreases in early childhood
hippocampal-cortical connectivity shows increases from childhood to adulthood
hippocampal volume shows an overall inverted-U shape over development
- increases during childhood
- begins to decrease in adolescence
there are region-specific volume changes
- adults have smaller hippocampal hear
- adults have larger hippocampal bodies
- adults have longer hppocampal tail
- CA3-DG and EC decrease in childhood
- CA1-2 subfields decrease with adult aging
Inaccessibility: Episodic Modularity
several aspects of brain development might account for childhood amnesia:
overall brain weight increase
language-specific modularity for simple narrative matures by ages 3-4
episodic memory relies on language to understand and generate simple narrative
episodic memory retrieval relies on narrative cues for sequence pattern completion
senile memory loss
some cognitive abilities worsen with age (WM, LTM, retrieval speed)
some improve with age (crystalized knowledge, vocab etc.)
there is “compensatory” activation of the PFC in both hemispheres in elderly subjects with good compared to poor recall
people who maintain overall cognitive functioning as they age may benefit from brain capacities of resilience or reserve, enabling them to sustain cognitive function despite the aging process
- more yo have them, more that you can lose - but you can recruit
is senile memory loss normal?
epidemiologic data following cognitive trajectories of older adults suggests normative cognitive decline may be dubious:
- there are multiple neurodegenerative and cerebrovascular conditions in old age that are associated with cognitive impairment, many of which are difficult to identify antemortem -hard to define this before death
- there is substantial heterogeneity in late life cognitive trajectories, with little change in some persons and complex nonlinear change in others, making it difficult to model change
- repeated administration of cognitive test is necessary to characterize change over time, but this test experience tends to enhance performance and thereby distort estimates of change and may obscure normative age-related cognitive decline
people decline differently it is hard to define
conclusions of neuropathology markers
after adjustment for the deleterious effects of non-normative pathologic processes, global cognitive decline was seen in about one-third of the participants and was related to mortality more than age (at death)
most cognitive loss is attributable to non-normative processes related to brain pathology or mortality and provide a little evidence that a late life cognitive loss reflects normative age-related processes
loss of cognition in old age mainly reflects non-normative factors
vascular dementia
the most severe form of vascular cognitive impairment
the second most common type of dementia (15 percent)
cause by many different vascular factors. ie/ cardiac arrest, arterial occlusion, hemorrhage. multiple white matter lesion
leads to severe cognitive deficits, including memory formation and retrieval
lewy body dementia
similar to parkinson’s dementia
loss of tegmental DA (dopamine) cells and forebrain cholinergic neurons
characterized by deposits of a-synuclein in lewy bodies
