Transcript Recordings in live chick embryo`s

The Use of Electrodes To Study
The Response Of Neurons In The
Auditory System of Live Chicks
Mobeen Farooq
Mentor: Professor José Luis Peña
Albert Einstein College of Medicine of
Yeshiva University
Introduction
•
FIG.
1.
Sound
localization
pathways in the barn owl. Time
What is the auditory system?
(ITD)
and
intensity
(ILD)
– The barn owl
information are processed in 2
parallel pathways that originate
in a bifurcation of the auditory
– The current model of thenerve
auditory
(nVIII) and converge in the
inferior colliculus (IC). The IC
system
projects to the forebrain () and
tectal (1) sound localization
pathways. NM, cochlear nucleus
magnocellularis; NA, cochlear
nucleus angularis; NL, nucleus
laminaris; LLDp, nucleus of the
lateral lemniscus pars posterior;
ICx, external nucleus of the
inferior colliculus; OT, optic
tectum; Ov, nucleus ovoidalis;
© Pérez ML et.
AAr, auditory arcopallium.
al 2006
© M. Konishi Caltech
Introduction Continued
• Why experiment with live chicks?
VS.
© english-country-garden
© cdb 2003
– No one has done recording in live chicks previously
– Preditor vs. Prey
– A chance for comparison
Methods & Materials
•
•
•
•
•
•
•
Chicken eggs
Stereotaxic apparatus
Motorized micromanipulator
The egg-warming device
Metal electrodes for recording the neurons
Pair of custom earphones
The use of a computer to analyze the response
properties of the neurons
Results
• No results at the moment!
Sensitivity of AAr units to ITD and ILD in a barn owl
with the ICX lesioned bilaterally. A and B: examples
of ITD tuning curves. C and D: examples of ILD
Cohen
et.
al
1998
tuning
curves.
©
References
Cohen YE, Miller GL, and Knudsen EI. Forebrain pathway for
auditory space processing in the barn owl. J Neurophysiol 79:
891-902, 1998.
Knudsen EI and Konishi M. A neural map of auditory space in the
owl. Science 200; 795-797, 1978.
Pérez ML, Peña JL. Comparison of midbrain and thalamic spacespecific neurons in barn owls. J Neurophysiol 95: 783-790.
Acknowledgements
Professor José Luis Peña
Mario, Lucia and Sharaad
Dr. Sat Bhattacharya
Harlem Children Society