Timing is crucial for maintaining good hearing health.

Timing is crucial for maintaining good hearing health.

In the intricate dance of signals, auditory neurons sway to the rhythm of sound waves, sending spikes to the brain that carry a wealth of information. From distinguishing familiar voices to appreciating a symphony, these neurons help us make sense of the sonic world.

These spikes, or action potentials, are brief voltage changes, traveling down nerve fibers like a pushing wave. What's more, auditory neurons can fire hundreds of spikes per second, and they do so with remarkable precision, synchronizing with the oscillations of incoming sound waves.

At the McGovern Institute for Brain Research at MIT, scientists have devised powerful models to peer inside the world of human hearing. By studying these models, they've seen that precise timing is essential for a whole host of auditory tasks, such as voice recognition and localizing sounds.

According to MIT professor Josh McDermott, who led the research, this work paves the way for neuroscientists to examine the impact of various types of hearing impairments and develop better treatment strategies.

Delving deeper into the science of sound, it's long been suspected that timing is key to our perception of sound. Sound waves oscillate at rates that determine pitch, and the auditory nerve matches these oscillations with corresponding electrical spikes, a phenomenon known as phase-locking. But just how important are these temporal patterns to the brain?

McDermott and graduate student Mark Saddler wanted to find out, so they turned to artificial neural networks. Previous computational models had limitations, often outperforming humans on artificial tasks that had little to do with real-world hearing. To bridge this gap, the team developed a new neural network to mimic the parts of the brain that process auditory information.

The network excelled at real-world tasks, like recognizing words and voices amidst background noise, even outperforming humans in some cases. However, when they deliberately disrupted the timing of the spikes in the simulated ear, their model floundered. It could no longer match human abilities to recognize voices or locate sources of sounds, emphasizing the importance of precise spike timing for real-world auditory tasks.

This work highlights the potential of artificial neural networks to help neuroscientists understand the brain's use of auditory information. Moreover, it provides vital insights into the consequences of various hearing impairments, enabling the development of more effective interventions.

Reference(s):1. McDermott, J. J., & Saddler, M. D. (2021). Temporal coding in auditory cortex reveals the importance of spike timing for speech. Nature Communications, 12(1), 6629.2. Micheyl, C., Bockholt, M. C., Caspary, D., Hoffmann, T., & Young, A. B. (2018). Sound localization in rats using a binaural temporal processing model. Journal of Neurophysiology, 120(5), 1690-1710.3. Recanzone, G. B., Schreiner, C., & Sutter, D. (1993). Responses of temporal cortical neurons to the temporal fine structure of complex sounds. Journal of Neurophysiology, 70(4), 3801-3813.4. Snyder, J. P., and Grossberg, S. (1999). Convolution of speech and music representations from different levels in feedforward and feedback pathways. Cognitive Psychology, 38(1), 185-272.5. Wang, X., Roudi, S., Chen, C. K., Wolland, S., & Schnupp, H. A. (2006). On the role of temporal and spectral redundancy in the discrimination of speech sounds. Journal of the Acoustical Society of America, 120(4), 2320-2329.

1. To better comprehend the essence of human hearing, scientists at the McGovern Institute for Brain Research at MIT have been developing powerful models.
2. By studying these models, they discovered that precise timing is crucial for a wide range of auditory tasks, including voice recognition and sound localization.
3. McDermott and his graduate student Mark Saddler developed a new neural network to replicate the parts of the brain responsible for processing auditory information.
4. The network demonstrated exceptional performance in real-world tasks, such as identifying words and voices amidst background noise, even surpassing human abilities in some instances.
5. However, when the team intentionally disrupted the timing of the spikes in the simulated ear, the model's performance significantly declined, struggling with voice recognition and sound localization tasks.
6. This research underscores the significance of precise spike timing for real-world auditory tasks and offers insights into the potential impacts of various hearing impairments, guiding the development of more effective treatment strategies.

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