Responses of Midbrain Auditory Neurons in Rats to FM and AM Tones Presented Simultaneously

Speech and other communication signals contain components of frequency and amplitude modulations (FM, AM) that often occur together. Auditory midbrain (or inferior colliculus, IC) is an important center for coding time-varying features of sounds. It remains unclear how IC neurons respond when FM and AM stimuli are both presented. Here we studied IC neurons in the urethane-anesthetized rats when animals were simultaneously stimulated with FM and AM tones. Of 122 units that were sensitive to the dual stimuli, the responses could be grossly divided into two types: one that resembled the respective responses to FM or AM stimuli presented separately (”simple” sensitivity, 45% of units), and another that appeared markedly different from their respective responses to FM or AM tones (”complex” sensitivity, 55%). These types of combinational sensitivities were further correlated with individual cell's frequency tuning pattern (response area) and with their common response pattern to FM and AM sounds. Results suggested that such combinational sensitivity could reflect local synaptic interactions on IC neurons and that the neural mechanisms could underlie more developed sensitivities to acoustic combinations found at the auditory cortex.

並列關鍵字

combinational sensitivity ； frequency modulation ； amplitude modulation ； inferior colliculus ； speech recognition

參考文獻

Chiu, T. W.,Liu, Y. D.,Poon, P. W. F.(1998).Transient frequency and intensity sensitivities of central auditory neurons estimated with sweep tone-a new approach.Chinese J. Physiol..41,133-138.

Google Scholar

Chiu, T. W.,Poon, P. W. F.(2000).Basic response determinants for amplitude modulation of single neurons in the auditory midbrain.Exp. Brain Res..134,237-245.

Google Scholar

Chiu, T. W.,Poon, P. W.(2007).Multiple-band trigger features of midbrain auditory neurons revealed in composite spectro-temporal receptive fields.Chinese J. Physiol..50,105-112.

Deutscher, A.,Kurt, S.,Scheich, H.,Schulze, H.(2006).Cortical and subcortical sides of auditory rhythms and pitches.NeuroReport.17,853-856.

Google Scholar

Eggermont, J. J.(1994).Temporal modulation transfer functions for AM and FM stimuli in cat auditory cortex. Effects of carrier type, modulating waveform and intensity.Hearing Res..74,51-66.

Google Scholar

延伸閱讀

Chiu, T. W., Liu, Y. D., & Poon, P. W. F. (1998). Transient Frequency and Intensity Sensitivities of Central Auditory Neurons Determined with Sweep Tone. The Chinese Journal of Physiology, 41(3), 133-138. https://www.airitilibrary.com/Article/Detail?DocID=03044920-199809-41-3-133-138-a
Cain, D., & Jen, P. H. S. (1999). The Effect of Sound Direction of Frequency Tuning in Mouse Inferior Collicular Neurons. The Chinese Journal of Physiology, 42(1), 1-8. https://www.airitilibrary.com/Article/Detail?DocID=03044920-199903-42-1-1-8-a
Chiu, T. W., & Poon, P. W. F. (2007). Multiple-Band Trigger Features of Midbrain Auditory Neurons Revealed in Composite Spectro-Temporal Receptive Fields. The Chinese Journal of Physiology, 50(3), 105-112. https://www.airitilibrary.com/Article/Detail?DocID=03044920-200706-50-3-105-112-a
Lin, A. M. Y., Wang, Y., Su, C. K., Lee, E. H. Y., Kuo, J. S., & Chai, C. Y. (1991). Responses of Neurons in Paramedian Reticular Nucleus to Chemical Stimulations and Alteration of Blood Pressure in Rats. The Chinese Journal of Physiology, 34(2), 187-200. https://www.airitilibrary.com/Article/Detail?DocID=03044920-199106-34-2-187-200-a
Jiang, H. J. (2013). Deep-brain microstimulation as a tool to explore functional characteristics of tactile neurons in rat brain [master's thesis, National Taiwan University]. Airiti Library. https://doi.org/10.6342/NTU.2013.01361

國際替代計量

Responses of Midbrain Auditory Neurons in Rats to FM and AM Tones Presented Simultaneously

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