These results imply that sound exposure does not change basal levels of neural activity in
inferior colliculus. Sound-exposed subjects who subsequently heard the 90 min 2 kHz tone burst exhibited increased c-fos expression levels, both near the 2 kHz region of interest and over a broad frequency range of
inferior colliculus (Figures 6(b) and 3).
Comparison of the auditory sensitivity of neurons in the cochlear nucleus and
inferior colliculus of young and aging C57BL/6J and CBA/J mice.
We demonstrated that ultrasonic waves, properly processed and delivered into the
inferior colliculus, by means of implanted electrodes, gave rise to a brain response modulated by echo signal features suggesting that spatial information sent by our stimulation signal was efficiently interpreted and encoded by the auditory system.
The superior colliculus, or optic tectum, relays visual information through its more superficial layers and somatosensory/multisensory information through its deeper layers, while the
inferior colliculus relays auditory information.
Salvi, "Functional reorganization in chinchilla
inferior colliculus associated with chronic and acute cochlear damage," Hearing Research, vol.
(b) It crosses the midline in the
inferior colliculusMore PV protein expression possibly represents more activated state of cortical neurons, since PV protein, a marker of cellular metabolic level [37, 38], increased in cochlear nucleus and
inferior colliculus of mice following noise exposure or sound stimulation [39, 40].
In our previous studies on the
inferior colliculus [6] and auditory cortex [16], we showed that developmentally enriched animals exhibited permanent changes of neuronal responsiveness; in particular, the neurons of the enriched animals were on average more sensitive (lower excitatory thresholds), more frequency selective (higher quality factor), and less nonmonotonic with respect to intensity coding (lower percentage of nonmonotonic rate-level functions).
High-intensity noise also can alter the normal neural coding processes of auditory signals in individual nuclei along the auditory pathway, including the cochlear nucleus,
inferior colliculus (IC), and auditory cortex [14, 16-20].
These results are consistent with our previous observation of SS-induced hyperactivity at the midfrequencies in the
inferior colliculus (IC) [14].
Our results also indicate that the prolonged latency of Wave V was greater than that of Wave III and thus suggest that reorganization of the subcortical auditory pathways may take place mainly in the lateral lemniscus, between the level of the superior olivary complex and the
inferior colliculus. We suggest that in the event of severe injury to the cortex, auditory function of the subcortical crossed pathway might be impaired and therefore reinforced by the uncrossed pathway.
The brachium of the left
inferior colliculus (IC) was sectioned (Figure 1).