Processing of Species-Specific Vocalizations in the Inferior Colliculus and Medial Geniculate Body of the Guinea Pig

1997 ◽  
pp. 431-441 ◽  
Author(s):  
J. Syka ◽  
J. Popelář ◽  
E. Kvašñák ◽  
J. Šuta ◽  
M. Jilek
Keyword(s):  
Guinea Pig ◽  
Inferior Colliculus ◽  
Medial Geniculate Body ◽  
Medial Geniculate ◽  
Species Specific

Representation of species-specific vocalizations in the medial geniculate body of the guinea pig

2007 ◽  
Vol 183 (3) ◽  
pp. 377-388 ◽  
Author(s):  
Daniel Šuta ◽  
Jiří Popelář ◽  
Eugen Kvašňák ◽  
Josef Syka
Keyword(s):  
Guinea Pig ◽  
Medial Geniculate Body ◽  
Medial Geniculate ◽  
Species Specific

Phase-Locked Responses to Pure Tones in the Auditory Thalamus

2007 ◽  
Vol 98 (4) ◽  
pp. 1941-1952 ◽  
Author(s):  
Mark N. Wallace ◽  
Lucy A. Anderson ◽  
Alan R. Palmer
Keyword(s):  
Guinea Pig ◽  
Inferior Colliculus ◽  
Phase Locking ◽  
Medial Geniculate Body ◽  
Low Frequency ◽  
Sine Wave ◽  
Temporal Coding ◽  
Auditory Thalamus ◽  
Medial Geniculate ◽  
The Brain

Accurate temporal coding of low-frequency tones by spikes that are locked to a particular phase of the sine wave (phase-locking), occurs among certain groups of neurons at various processing levels in the brain. Phase-locked responses have previously been studied in the inferior colliculus and neocortex of the guinea pig and we now describe the responses in the auditory thalamus. Recordings were made from 241 single units, 32 (13%) of which showed phase-locked responses. Units with phase-locked responses were mainly (82%) located in the ventral division of the medial geniculate body (MGB), and also the medial division (18%), but were not found in the dorsal or shell divisions. The upper limiting frequency of phase-locking varied greatly between units (60–1,100 Hz) and between anatomical divisions. The upper limit in the ventral division was 520 Hz and in the medial was 1,100 Hz. The range of steady-state delays calculated from phase plots also varied: ventral division, 8.6–14 ms (mean 11.1 ms; SD 1.56); medial division, 7.5–11 ms (mean 9.3 ms; SD 1.5). Taken together, these measurements are consistent with the medial division receiving a phase-locked input directly from the brain stem, without an obligatory relay in the inferior colliculus. Cells in both the ventral and medial divisions of the MGB showed a response that phase-locked to the fundamental frequency of a guinea pig purr and may be involved in analyzing communication calls.

scholarly journals Inhibitory Projections from the Inferior Colliculus to the Medial Geniculate body Originate from Four Subtypes of GABAergic Cells

eNeuro ◽  
2018 ◽  
Vol 5 (5) ◽  
pp. ENEURO.0406-18.2018 ◽  
Author(s):  
N. L. Beebe ◽  
J. G. Mellott ◽  
B. R. Schofield
Keyword(s):  
Inferior Colliculus ◽  
Medial Geniculate Body ◽  
Medial Geniculate

The cocaine- and amphetamine-regulated transcript, calbindin, calretinin and parvalbumin immunoreactivity in the medial geniculate body of the guinea pig

2014 ◽  
Vol 59-60 ◽  
pp. 17-28 ◽  
Author(s):  
Janusz Najdzion ◽  
Barbara Wasilewska ◽  
Krystyna Bogus-Nowakowska ◽  
Anna Robak
Keyword(s):  
Guinea Pig ◽  
Medial Geniculate Body ◽  
Medial Geniculate

scholarly journals Antidromic Activation Reveals Tonotopically Organized Projections From Primary Auditory Cortex to the Central Nucleus of the Inferior Colliculus in Guinea Pig

2007 ◽  
Vol 97 (2) ◽  
pp. 1413-1427 ◽  
Author(s):  
Hubert H. Lim ◽  
David J. Anderson
Keyword(s):  
Auditory Cortex ◽  
Inferior Colliculus ◽  
Spatial Organization ◽  
Medial Geniculate Body ◽  
Primary Auditory Cortex ◽  
Central Nucleus ◽  
Antidromic Activation ◽  
Antidromic Stimulation ◽  
Medial Geniculate ◽  
Layer V

The inferior colliculus (IC) is highly modulated by descending projections from higher auditory and nonauditory centers. Traditionally, corticofugal fibers were believed to project mainly to the extralemniscal IC regions. However, there is some anatomical evidence suggesting that a substantial number of fibers from the primary auditory cortex (A1) project into the IC central nucleus (ICC) and appear to be tonotopically organized. In this study, we used antidromic stimulation combined with other electrophysiological techniques to further investigate the spatial organization of descending fibers from A1 to the ICC in ketamine-anesthetized guinea pigs. Based on our findings, corticofugal fibers originate predominantly from layer V of A1, are amply scattered throughout the ICC and only project to ICC neurons with a similar best frequency (BF). This strict tonotopic pattern suggests that these corticofugal projections are involved with modulating spectral features of sound. Along the isofrequency dimension of the ICC, there appears to be some differences in projection patterns that depend on BF region and possibly isofrequency location within A1 and may be indicative of different descending coding strategies. Furthermore, the success of the antidromic stimulation method in our study demonstrates that it can be used to investigate some of the functional properties associated with corticofugal projections to the ICC as well as to other regions (e.g., medial geniculate body, cochlear nucleus). Such a method can address some of the limitations with current anatomical techniques for studying the auditory corticofugal system.

Sign in / Sign up

Export Citation Format

Share Document