Dataset Information

Spatial organization of frequency preference and selectivity in the human inferior colliculus.

ABSTRACT: To date, the functional organization of human auditory subcortical structures can only be inferred from animal models. Here we use high-resolution functional magnetic resonance imaging at ultra-high magnetic fields (7T) to map the organization of spectral responses in the human inferior colliculus, a subcortical structure fundamental for sound processing. We reveal a tonotopic map with a spatial gradient of preferred frequencies approximately oriented from dorsolateral (low frequencies) to ventromedial (high frequencies) locations. Furthermore, we observe a spatial organization of spectral selectivity (tuning) of functional magnetic resonance imaging responses in the human inferior colliculus. Along isofrequency contours, functional magnetic resonance imaging tuning is narrowest in central locations and broadest in the surrounding regions. Finally, by comparing subcortical and cortical auditory areas we show that functional magnetic resonance imaging tuning is narrower in human inferior colliculus than on the cortical surface. Our findings pave the way to noninvasive investigations of sound processing in human subcortical nuclei and for studying the interplay between subcortical and cortical neuronal populations.

SUBMITTER: De Martino F

PROVIDER: S-EPMC3556928 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Spatial organization of frequency preference and selectivity in the human inferior colliculus.

De Martino Federico F Moerel Michelle M van de Moortele Pierre-Francois PF Ugurbil Kamil K Goebel Rainer R Yacoub Essa E Formisano Elia E

Nature communications 20130101

To date, the functional organization of human auditory subcortical structures can only be inferred from animal models. Here we use high-resolution functional magnetic resonance imaging at ultra-high magnetic fields (7T) to map the organization of spectral responses in the human inferior colliculus, a subcortical structure fundamental for sound processing. We reveal a tonotopic map with a spatial gradient of preferred frequencies approximately oriented from dorsolateral (low frequencies) to ventr ...[more]

PMID: 23340426

Similar Datasets

Project description:The inferior colliculus (IC) is a critical integration center in the auditory pathway. However, because the inputs to the IC have typically been studied by the use of conventional anterograde and retrograde tracers, the neuronal organization and cell-type-specific connections in the IC are poorly understood. Here, we used monosynaptic rabies tracing and in situ hybridization combined with excitatory and inhibitory Cre transgenic mouse lines of both sexes to characterize the brainwide and cell-type-specific inputs to specific neuron types within the lemniscal IC core and nonlemniscal IC shell. We observed that both excitatory and inhibitory neurons of the IC shell predominantly received ascending inputs rather than descending or core inputs. Correlation and clustering analyses revealed two groups of excitatory neurons in the shell: one received inputs from a combination of ascending nuclei, and the other received inputs from a combination of descending nuclei, neuromodulatory nuclei, and the contralateral IC. In contrast, inhibitory neurons in the core received inputs from the same combination of all nuclei. After normalizing the extrinsic inputs, we found that core inhibitory neurons received a higher proportion of inhibitory inputs from the ventral nucleus of the lateral lemniscus than excitatory neurons. Furthermore, the inhibitory neurons preferentially received inhibitory inputs from the contralateral IC shell. Because IC inhibitory neurons innervate the thalamus and contralateral IC, the inhibitory inputs we uncovered here suggest two long-range disinhibitory circuits. In summary, we found: (1) dominant ascending inputs to the shell, (2) two subpopulations of shell excitatory neurons, and (3) two disinhibitory circuits.SIGNIFICANCE STATEMENT Sound undergoes extensive processing in the brainstem. The inferior colliculus (IC) core is classically viewed as the integration center for ascending auditory information, whereas the IC shell integrates descending feedback information. Here, we demonstrate that ascending inputs predominated in the IC shell but appeared to be separated from the descending inputs. The presence of inhibitory projection neurons is a unique feature of the auditory ascending pathways, but the connections of these neurons are poorly understood. Interestingly, we also found that inhibitory neurons in the IC core and shell preferentially received inhibitory inputs from ascending nuclei and contralateral IC, respectively. Therefore, our results suggest a bipartite domain in the IC shell and disinhibitory circuits in the IC.

Dataset Information

Spatial organization of frequency preference and selectivity in the human inferior colliculus.

Publications

Spatial organization of frequency preference and selectivity in the human inferior colliculus.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets