Primary innervation of the avian and mammalian cochlear nucleus

Ryugo, David K.; Parks, Thomas N.

doi:10.1016/s0361-9230(03)00049-2

Cited by 115 publications

(106 citation statements)

References 222 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The ability of these models to predict IC responses in the budgerigar highlights an emerging pattern of broad similarities in auditory function between birds and mammals up to at least the level of the auditory midbrain (Ryugo and Parks 2003;Woolley and Portfors 2013). While birds and mammals exhibit differences in the anatomy of the cochlea related to extension of the upper frequency limit of hearing in mammals (Manley 2010), auditory nerve fibers in both groups show similar ranges of spontaneous activity, minimum thresholds for tone stimuli, frequency tuning bandwidth as a function of BF, and dynamic range/rate saturation (Sachs et al 1974;Manley et al 1985).…”

Section: Discussionmentioning

confidence: 99%

Midbrain Synchrony to Envelope Structure Supports Behavioral Sensitivity to Single-Formant Vowel-Like Sounds in Noise

Henry

Abrams

Forst

et al. 2016

JARO

View full text Add to dashboard Cite

Vowels make a strong contribution to speech perception under natural conditions. Vowels are encoded in the auditory nerve primarily through neural synchrony to temporal fine structure and to envelope fluctuations rather than through average discharge rate. Neural synchrony is thought to contribute less to vowel coding in central auditory nuclei, consistent with more limited synchronization to fine structure and the emergence of average-rate coding of envelope fluctuations. However, this hypothesis is largely unexplored, especially in background noise. The present study examined coding mechanisms at the level of the midbrain that support behavioral sensitivity to simple vowel-like sounds using neurophysiological recordings and matched behavioral experiments in the budgerigar. Stimuli were harmonic tone complexes with energy concentrated at one spectral peak, or formant frequency, presented in quiet and in noise. Behavioral thresholds for formant-frequency discrimination decreased with increasing amplitude of stimulus envelope fluctuations, increased in noise, and were similar between budgerigars and humans. Multiunit recordings in awake birds showed that the midbrain encodes vowel-like sounds both through response synchrony to envelope structure and through average rate. Whereas neural discrimination thresholds based on either coding scheme were sufficient to support behavioral thresholds in quiet, only synchrony-based neural thresholds could account for behavioral thresholds in background noise. These results reveal an incomplete transformation to average-rate coding of vowel-like sounds in the midbrain. Model simulations suggest that this transformation emerges due to modulation tuning, which is shared between birds and mammals. Furthermore, the results underscore the behavioral relevance of envelope synchrony in the midbrain for detection of small differences in vowel formant frequency under real-world listening conditions.

show abstract

Section: Discussionmentioning

confidence: 99%

Midbrain Synchrony to Envelope Structure Supports Behavioral Sensitivity to Single-Formant Vowel-Like Sounds in Noise

Henry

Abrams

Forst

et al. 2016

JARO

View full text Add to dashboard Cite

show abstract

“…On the basis of cytoarchitectonic features, the cochlear nuclei of mammals can be divided into three divisions: the anteroventral cochlear nucleus, the posteroventral cochlear nucleus, and the dorsal cochlear nucleus (Ryugo and Parks, 2003). By using genetic fate mapping, Farago et al (2006) proposed a model in which the cochlear nuclei derive from r2 to r5; the anteroventral cochlear nucleus mainly derives from r2 and r3, the posteroventral cochlear nucleus from r4, and the dorsal cochlear nucleus from r5.…”

Section: Discussionmentioning

confidence: 99%

Visualization of two distinct classes of neurons by gad2 and zic1 promoter/enhancer elements in the dorsal hindbrain of developing zebrafish reveals neuronal connectivity related to the auditory and lateral line systems

Sassa

Aizawa

Okamoto

2007

Developmental Dynamics

View full text Add to dashboard Cite

The dorsal hindbrain includes distinct classes of neurons for processing various sensory stimuli, but the developmental aspects of these neurons remain largely unknown. We identify here two distinct classes of neurons in the dorsal hindbrain of developing zebrafish: (1) neurons that express the inhibitory neuronal marker Gad1/2, and (2) neurons that express the zn-5 antigen and Lhx2/9 and require the basic helix-loop-helix transcription factor Atoh1a for development. Neurons were traced to their axon terminals by expressing green fluorescent protein using the Gal4VP16-UAS (UAS, upstream activating sequences) system in combination with the promoter/enhancer regions of gad2 for the Gad1/2(؉) neurons and zic1 for the zn-5(؉)Lhx2/9(؉) neurons. The Gad1/2(؉) neurons projected to the contralateral hindbrain, while the zn-5(؉)Lhx2/9(؉) neurons projected to the contralateral midbrain torus semicircularis, suggesting a role in auditory and lateral line sensory processing. Comparison of these projections with those from the cochlear nuclei to the inferior colliculus in mammals suggests similarities across vertebrate species. Developmental Dynamics 236:706 -718, 2007.

show abstract

“…The three types of cells receive direct input from the auditory nerve and using the same type of contact (button endings) with slightly different time constants (Ryugo and Parks, 2003). The main difference reside in the CF span: D-stellate neurons receive inputs from a wide cochlear region (CF span ranging between 1 and 1.5 octaves), while T-stellate and vertical cells are aligned with nerve fibers and narrowband.…”

Section: Innervation Of Cn Cellsmentioning

confidence: 99%

A biophysical model for modulation frequency encoding in the cochlear nucleus

Eguía

García

Romano

2010

Journal of Physiology-Paris

View full text Add to dashboard Cite

a b s t r a c tEncoding of amplitude modulated (AM) acoustical signals is one of the most compelling tasks for the mammalian auditory system: environmental sounds, after being filtered and transduced by the cochlea, become narrowband AM signals. Despite much experimental work dedicated to the comprehension of auditory system extraction and encoding of AM information, the neural mechanisms underlying this remarkable feature are far from being understood (Joris et al., 2004). One of the most accepted theories for this processing is the existence of a periodotopic organization (based on temporal information) across the more studied tonotopic axis (Frisina et al., 1990b).In this work, we will review some recent advances in the study of the mechanisms involved in neural processing of AM sounds, and propose an integrated model that runs from the external ear, through the cochlea and the auditory nerve, up to a sub-circuit of the cochlear nucleus (the first processing unit in the central auditory system). We will show that varying the amount of inhibition in our model we can obtain a range of best modulation frequencies (BMF) in some principal cells of the cochlear nucleus. This could be a basis for a, synchronicity based, low-level periodotopic organization.

show abstract

Primary innervation of the avian and mammalian cochlear nucleus

Cited by 115 publications

References 222 publications

Midbrain Synchrony to Envelope Structure Supports Behavioral Sensitivity to Single-Formant Vowel-Like Sounds in Noise

Midbrain Synchrony to Envelope Structure Supports Behavioral Sensitivity to Single-Formant Vowel-Like Sounds in Noise

Visualization of two distinct classes of neurons by gad2 and zic1 promoter/enhancer elements in the dorsal hindbrain of developing zebrafish reveals neuronal connectivity related to the auditory and lateral line systems

A biophysical model for modulation frequency encoding in the cochlear nucleus

Contact Info

Product

Resources

About