Lecture 25 Flashcards
what do birds need to do to master a song?
learn to sing song themselves and be able to hear themselves throughout the learning process
whats the process in birds to learn a song?
- internalize mental representation of song then retrieve during practice to assess own performance
can birds learn songs accurately if deaf?
if they become deaf after hearing the song of a conspecific then yes but if deaf then trying to learn to sing then unable to sing accurately
how does performance monitoring work in songbords?
create a template of the songs that are retrieved during performance and compare it to the actual signal to check whether intended and actual output are the same
what is needed to do behavioral corrections?
error signals
difficulty in songbirds to master a song without hearing themselves is parallel to ________ ___________ in deaf children
language acquisition
what are songbirds a good model of?
human speech learning which proves to be valuable bc vocal learning that is complex is rare in animal kingdom
what is the network of brain structures in songbirds referred to as?
song system
what regions are part of the song system?
planning/executing motor commands- motor control
perceptual learning sounds - processing auditory info
evaluating auditory feedback- evaluating auditory feedback
what does the motor pathway consist of?
HVc and RA
what does the HVc and RA correlate to?
song production
what do lesions in HVc/RA nuclei do?
prevent normal learning of songs and muteness
whats the purpose of HVc?
encode higher-level song structure
- separating the beginning, middle and end of a song
what does microstimulation to HVc cause?
birds to restart song
what’s the purpose of RA?
encode more local-level info
- individual notes
what does microstimulation of RA cause?
changes the way individual notes sound
what is the Field L complex comparable to?
PAC
what does the Field L complex do
has highly specialized neurons that are tuned to respond to songbird’s own song
what is the anterior forebrain pathway comparable to?
basal-ganglia-thalamo-cortical loop
what do lesions in AFP affect?
prevent acquisition of new song
what is Area X similar to?
basal ganglia
where do pathways carry info to?
forwards (feedforward) and backwards (feedback)
- without feedback then there is incomplete conscious awareness
- forwards is for visual perception
what does heavy involvement of dopaminergic neurons do?
performance monitoring and error signals
what does DLM parallel?
thalamus
what does LMAN parallel?
frontal cortex
what are some evidences that show predispositions towards learning songs of conspecifics?
- increase heart rate and produce more begging calls when exposed to songs of conspecifics
- preference to learn songs from conspecifics over others
- develop songs that retains some species-specific characteristics when raised in isolation
what do human infants have predisposition towards?
faces
- genetic
why is the sensitive period important?
changes caused by early exposure to specific languages
- important for speaking/understanding language so will be be able to be recognized/reproduced if learned before adolescence
describe the critical window in songbirds
exposure to songs after a certain developmental window never become learned and integrated into their song repertoire
what happened to birds raised in isolation for 100 days?
when exposed to conspecifics they don’t typically develop “normal” songs
what is sensory learning?
- internalizing a mental representation of a song you hear
what is sensorimotor learning?
learning how to reproduce a song yourself
what are closed-learners?
more fixed windows in which they are able to learn new songs
- more constraint
- zebra finches and white-crowned sparrows
what are open-learners?
capable of learning new songs at various points throughout life
- canaries and starlings
- seasonal cycle
why are there differences in abilities between open and closed learners?
hormone profiles
- testosterone fluctuate with changes in sensorimotor learning (higher in spring when new songs may be easily learned)
- experimentally depleting testosterone can impair song crystallization (transformation of newly learned mental representation into more durable form)
what increases singing behavior?
androgens
- enhancements to motor performance
what modulates plasticity?
structural changes, electrophysiological changes
does neurogenesis occur in humans?
yes
- adult human brain undergoes robust neurogenesis in hippocampus and olfactory bulb
what did Goldman and Nottebohm report?
HVc experiences significant neurogenesis with rates often changing with seasons
what can induce neurogenesis?
pharmaceutical manipulations
environmental factors
- interact with seasonality
what do songbirds model?
specific experimental advantages
- fast development
- abdundance
- diversity
- ease at which various kinds of measures can be taken
what is a limitation to using songbirds?
the divergence in the evolutionary timelines can make their study less generalizable to humans compared to rats or other non-human primates
- differences can also serve to highlight relevant mechanisms that mediate human experience
