Intro | Auditory Cortex | Cochlear Nucleus | Inferior Colliculus | Medial Geniculate | Superior Olive
Part 1: Image-Mapped Tutorial
Part 2: Matching Self-Test
Part 3: Multiple-Choice Self-Test
The fourth synapse in the primary auditory pathway occurs in the Medial Geniculate nucleus of the thalamus. The ventral and dorsal regions of the medial geniculate nuclei receive projections from two distinct pathways leaving the inferior colliculi. The ventral, medial geniculate nucleus projects to the primary auditory cortex, whereas the dorsal, medial geniculate nucleus projects to the secondary auditory cortex.
| Advanced |
A rather extensive research program has studied the projections of the medial geniculate nucleus of the thalamus to two structures of the subcortical forebrain, the lateral nucleus of the dorsal amygdala and the posterior neostriatum. This research indicates a role for these connections in the mediation of emotional responses to auditory stimuli (Hennevin, Maho & Hars, 1998; Poremba & Gabriel, 1997). The interaction of processing between the medial geniculate nucleus, posterior neostriatum and the dorsal amygdala appears to be involved in the conditioning of fear responses to sounds.
| References |
Hennevin, E., Maho, C. & Hars, B. (1998). Neuronal plasticity induced by fear conditioning is expressed during paradoxical sleep: evidence from simultaneous recordings in the lateral amygdala and the medial geniculate in rats. Behavioral Neuroscience, 112(4), 839-862.
Poremba, A. & Gabriel, M. (1997). Medial geniculate lesions block amygdalar and cingulothalamic learning-related neuronal activity. Journal of Neuroscience, 17(21), 8645-8655.