A neural connection between the trigeminal ganglion and auditory brainstem was investigated by using retrograde anterograde tract tracing methods: iontophoretic injections of biocytin or biotinylated dextran-amine (BDA) were made into guinea pig ganglion, labeling examined in cochlear nucleus superior olivary complex. Terminal after BDA found to be most dense marginal cell area secondarily magnocellular ventral (VCN). Anterograde also seen shell regions lateral complex periolivary regions....

Abstract Multisensory neurons in the dorsal cochlear nucleus (DCN) achieve their bimodal response properties [Shore (2005) Eur. J. Neurosci. , 21 3334–3348] by integrating auditory input via VIIIth nerve fibers with somatosensory axons of granule cells et al. (2000) Comp. Neurol. 419 271–285; Zhou & Shore (2004) Res. 78 901–907]. A unique feature multisensory is propensity for receiving cross‐modal compensation following sensory deprivation. Thus, we investigated possibility that...

Abstract A necessary requirement for multisensory integration is the convergence of pathways from different senses. The dorsal cochlear nucleus (DCN) receives auditory input directly via VIIIth nerve and somatosensory indirectly Vth granule cells. Multisensory may occur in DCN cells that receive both trigeminal input, such as fusiform cell. We investigated system influences on guinea pig by stimulating ganglion while recording spontaneous sound‐driven activity neurons. bipolar electrode was...

The dorsal cochlear nucleus (DCN) is the first neural site of bimodal auditory-somatosensory integration. Previous studies have shown that stimulation somatosensory pathways results in immediate suppression or enhancement subsequent acoustically evoked discharges. In unimpaired auditory system predominates. However, damage to input pathway leads excitatory inputs nucleus, changing their effects on DCN neurons (Shore et al., 2008; Zeng 2009). Given well described connection between and...

Noninvasive bimodal auditory stimulation targets the dorsal cochlear nucleus and reduces tinnitus in guinea pigs humans.

Tinnitus, the perception of phantom sounds, is thought to arise from increased neural synchrony, which facilitates perceptual binding and creates salient sensory features in absence physical stimuli. In auditory cortex, spontaneous cross-unit synchrony single-unit bursting are de facto physiological correlates tinnitus. However, it unknown whether neurons dorsal cochlear nucleus (DCN), putative tinnitus-induction site, exhibit synchrony. Using a temporary-threshold shift model gap-prepulse...

Loss of synapses between spiral ganglion neurons and inner hair cells (IHC synaptopathy) leads to an auditory neuropathy called hidden hearing loss (HHL) characterized by normal thresholds but reduced amplitude sound-evoked potentials. It has been proposed that synaptopathy HHL result in poor performance challenging tasks despite a audiogram. However, this only tested animals after exposure noise or ototoxic drugs, which can cause deficits beyond synaptopathy. Furthermore, the impact...

Abstract Projections of glutamatergic somatosensory and auditory fibers to the cochlear nucleus (CN) are mostly nonoverlapping: projections from spinal trigeminal (Sp5) terminate primarily in granule cell domains (GCD) CN, whereas type I nerve (ANFs) project magnocellular areas VCN (VCNm) deep layers Dorsal CN (DCN). Vesicular glutamate transporters (VGLUTs), which selectively package into synaptic vesicles, have different isoforms associated with distinct subtypes excitatory neurons. Here...

Abstract In addition to input from auditory centers, the cochlear nucleus (CN) receives inputs nonauditory including trigeminal sensory complex. The detailed anatomy, however, and functional implications of innervation system are not fully understood. We demonstrated previously that ganglion projects CN, with terminal labeling most dense in marginal cell area secondarily magnocellular ventral (VCN). continue this line study by investigating projection spinal CN guinea pig. After injections...

In addition to ascending auditory inputs, the external cortex of inferior colliculus (ICX) receives prominent somatosensory inputs. To elucidate extent interaction between and representations at level IC, we explored dual projections from cochlear nucleus (CN) spinal trigeminal (Sp5) (IC) in guinea pig, using both retrograde anterograde tracing techniques. Injections tracers into ICX resulted cell-labeling primarily contralateral DCN pars interpolaris caudalis Sp5. Labeled cells were either...

Integration of multimodal information is essential for understanding complex environments. In the auditory system, multisensory integration first occurs in cochlear nucleus (CN), where nerve and somatosensory pathways converge (Shore, 2005). A unique feature neurons their propensity to receive cross-modal compensation after deafening. Based on our findings that vesicular glutamate transporters, VGLUT1 VGLUT2, are differentially associated with inputs CN, respectively (Zhou et al., 2007), we...

Tinnitus and cochlear damage have been associated with changes in somatosensory-auditory integration plasticity the dorsal nucleus (DCN). Recently, we demonstrated vivo that DCN bimodal is stimulus timing-dependent, Hebbian anti-Hebbian timing rules reflect vitro spike timing-dependent plasticity. In this study, assessed dependence of a tinnitus model. Guinea pigs were exposed to narrowband noise produced temporary elevation auditory brainstem response thresholds. A total 60% guinea...

Tinnitus or ringing of the ears is a subjective phantom sensation necessitating behavioral models that objectively demonstrate existence and quality tinnitus sensation. The gap detection test uses acoustic startle response elicited by loud noise pulses its gating suppression preceding sub-startling prepulses. Gaps in bands serve as prepulses, assuming ongoing masks results impaired detection. This has shown reliability rats, mice, gerbils. No data exists for guinea pig so far, although...

The cochlear nucleus (CN) receives innervation from auditory and somatosensory structures, which can be identified using vesicular glutamate transporters, VGLUT1 VGLUT2. is highly expressed in the magnocellular ventral CN (VCN), nerve inputs. VGLUT2 predominantly granule cell domain (GCD), nonauditory inputs nuclei, including spinal trigeminal (Sp5) cuneate (Cu). Two weeks after unilateral deafening significantly decreased ipsilateral VCN while increased GCD (Zeng et al., 2009), putatively...