José Luis Peña

Assistant Professor

Neural bases of behavior and Neural coding.

Kennedy Center
Room 529
(718) 430-4088
jpena@aecom.yu.edu

 

 

All auditory information essential for discriminating and identifying sounds ascends through the brainstem auditory nuclei.  Our goal is to determine how multiple information dimensions flow and are represented in the avian brain using physiological and theoretical approaches.

A primary advantage of using barn owls for the exploration of auditory processing is the substantial body of behavioral, anatomical and neurophysiological work that has elucidated the mechanisms of sound localization. The main cues owls use to compute sound direction are the interaural level difference (ILD) and the interaural time difference (ITD). Two independent brainstem pathways process ITD and ILD and converge in the midbrain, where a map of auditory space emerges. This computation evokes a head-orienting behavior towards the sound source. Thus, in barn owls, the neural algorithm for sound localization can be viewed as a system in which two input variables (ITD and ILD) are processed in parallel in order to control two output variables (horizontal and vertical coordinates of head saccades).

We have used analytical models to describe the neural response in the owl’s auditory system. This approach has guided our experiments and aided the interpretation of our findings. Based on behavioral experiments with humans, a similar approach to describe humans’ sound localization has also been developed. However, due to a lack of neural data in humans, the predictive power of models of sound localization has been a persistent question. Our studies in barn owls address this issue.

In the auditory midbrain, not only does spatial tuning emerge but it is calibrated through visually-instructed plasticity. The midbrain is thus an attractive structure to perform in vitro studies of cellular and synaptic bases of sound localization as well as of experience-dependent plasticity. We have used chicken brain slices to approach these questions. In this preparation, we found endocannabinoid-dependent plasticity mediated by both presynaptic and postsynaptic effects. This process can not only favour synapse-specific modulations but also change the threshold for subsequent synaptic plasticity.

 

Selected Publications

Perez ML, Shanbhag SJ, Peña JL (2009) Auditory spatial tuning at the cross-roads of the midbrain and forebrain. Journal of Neurophysiology, in press.

Penzo MA, Peña JL (2009) Endocannabinoid-mediated long-term depression in the avian midbrain expressed presynaptically and postsynaptically. Journal of Neuroscience 29: 4131-4139.

Fischer BJ, Peña JL (2009) Bilateral matching of frequency tuning in neural cross-correlators of the owl. Biological Cybernetics 100: 521-531.

Fischer BJ, Christianson GB, Peña JL (2008) Cross-correlation in the auditory coincidence detectors of owls. Journal of Neuroscience 28: 8107-8115.

Wild JM, Kubke MF, Peña JL (2008) A pathway for predation in the brain of the barn owl (Tyto alba): projections of the gracile nucleus to the "claw area" of the rostral wulst via the dorsal thalamus. Journal of Comparative Neurology 509: 156-166.

Fischer B, Peña JL, Konishi M (2007) Emergence of multiplicative auditory responses in the midbrain of the barn owl. Journal of Neurophysiology 98: 1181-1193.

Christianson GB, Peña JL (2007) Preservation of spectrotemporal tuning between the nucleus laminaris and the inferior colliculus of the barn owl. Journal of Neurophysiology 97: 3544-3553.

Christianson GB, Peña JL (2006) Noise reduction of coincidence detector output by the inferior colliculus of the barn owl. Journal of Neuroscience 26: 5948-5954.

Pérez ML, Peña JL (2006) Comparison of midbrain and thalamic space-specific neurons in barn owls. Journal of Neurophysiology 95: 783-790.

Peña JL, Konishi, M (2004) Robustness of multiplicative processes in auditory spatial tuning. Journal of Neuroscience 24: 8907-8910.

Peña JL (2003) Binaural processing in the synthesis of auditory spatial receptive fields. Biological Cybernetics 89: 371-377.

Peña JL, Konishi M (2002) From postsynaptic potentials to spikes in the genesis of auditory spatial receptive fields. Journal of Neuroscience 22: 5652-5658.

Peña JL, Viete S, Funabiki K, Saberi K, Konishi M (2001) Cochlear and neural delays for coincidence detection in owls. Journal of Neuroscience 21: 9455-9459.

Peña JL, Konishi M (2001) Auditory spatial receptive fields created by multiplication. Science 292: 249-252.

Peña JL, Konishi M (2000) Cellular mechanisms for resolving phase ambiguity in the owl's inferior colliculus. Proc. Nat. Acad. Sci. USA 97: 11787-11792.