Birdsong

Question 1

Why study zebra finch

Answer 1

one stereotyped song, no movement during song so can isolate neurons for song, many harmonics in song

Question 2

How does finch learn song

Answer 2

Combination of innate aspects and learn from tutors, juveniles practice when alone! (undirected). The last hatchling does best.
If never get tutor, some innate aspects but mostly bad. Heartbeat rises when hear own song, preference for own species song innate
Can remember song post 3 months!

Question 3

Sensorimotor Integration

Answer 3

Taking sound info and translating it into motor output when learning how to make a song, dopamine reinforcement when hear self, practicing

Question 4

Anatomy of throat finch

Answer 4

2 syrinxes, separate, no corpus callosum, operate independently

Question 5

Motor pathway

Answer 5

HVC -> RA -> Hypoglossal -> Syrinxes

Question 6

Auditory processing in finches

Answer 6

Aud Path sends to HVC too, for practicing
HVC spikes to SONG (not reversed song), aud path spikes to aud info

Question 7

Song Production finches

Answer 7

Contract air sac muscles, RA drives motor function, higher syrinx tension = higher freq
Alternate syrinx activity, faster switch = genetic fitness

Question 8

Effects of perturbing HVC

Answer 8

Elemental disturbances, song restarts/truncates, messes up the rhythm

Question 9

Effects of RA Lesion

Answer 9

Song no longer stereotyped, falls apart, needs it for good production

Question 10

Recording from song areas

Answer 10

Breath muscle spikes look like song pattern, in time
RA stereotyped spiking not in song pattern relationship, abstract rep of song
HVC = spike once at each syllable/motif,

Question 11

Synfire Chain Model

Answer 11

HVC spike to RA to muscles, pass baton to next HVC group to other group of RA/muscles
Sequential chain for song production

Question 12

HVC control song tempo

Answer 12

Cool HVC = song slows down, stretches out
warm = goes faster, speed up for female directed
BREATH TIMING DOESNT STRETCH OUT, SO LIKELY CONTROL SYNCHRONICITY OF SYRINXES

Question 13

Proposed network of song production

Answer 13

Continuous model = HVC does all
Distributed = HVC does but get syn input
Subnetwork = TRUE, HVC does sylls with RA and gets syn input from breath muscles

Question 14

Thalamus and syn input

Answer 14

Sends breath info to HVC to syn Syrinxes
Lesion thalamus = no song structure no syls, no fire pattern

Question 15

Shock HVC vs Uva (thalamus)

Answer 15

Shock HVC = song fully stops 80 ms later
Shock Uva = can’t start next syl, truncate at switch, (no initiation from Uva!)

Question 16

Sleep and Songs

Answer 16

RA same firing pattern in sleep, practicing
muscles engaged in sleep for motor practice
Lesion Uva = still practice in sleep, less stereotyped during sleep, timing not as important

Question 17

Song Memory Site

Answer 17

NCM does memory storage

Question 18

Anterior Forebrain Pathway and Area X uses

Answer 18

HVC to Area X to LMAN to RA
AREA X NOT NECESSARY FOR PRODUCTION
Area X IS needed for song LEARNING
Active during undirected songs only (practicing)
Immediate early genes activate during brain activation and transcribe other genes that allow for song crystallization

Question 19

Directed vs undirected song

Answer 19

Directed faster, longer, and less variable in frequency (more tuned)

Question 20

LMAN functions

Answer 20

Imposes variability onto RA, inhibit LMAN = song not as variable, RA firing more locked
Variability helps learning, error driven learning reinforcement

Question 21

AFP and variability (anterior forebrain path)

Answer 21

AFP generates motor variability onto RA
At early learning stage, NO HVC/UVA input onto RA
During plastic learning phase, both AFP/HVC input
Adult phase = crystallized, ONLY HVC/UVA input, no AFP/LMAN

Question 22

Adaptive Motor variability

Answer 22

finch can learn/adapt given error signals (experiment white noise, learned to sing lower pitch)
Lesion LMAN = revert back to before learning, LMAN DRIVES ADAPTATION/LEARNING
If allowed over night, variability consolidated and the song changes