Transneuronal retrograde degeneration of retinal ganglion cells following restricted lesions of striate cortex in the monkey

Abstract

Transneuronal retrograde degeneration of retinal ganglion cells follows extensive striate cortical removal in macaque monkeys. Its extent depends on the age of the monkey at operation, post-operative survival, species and retinal eccentricity. Some studies of human patients with occipital lobe injury have found no evidence for transneuronal retrograde degeneration, suggesting that either degeneration may not occur or, if present, it is caused directly by secondary damage impinging upon the underlying white matter or the blood supply to the dorsal lateral geniculate nucleus and optic tract. We therefore studied retinal ganglion cell degeneration in three macaques in which only the striate cortex corresponding to the macular retina had been removed, thereby sparing extrastriate cortex and precluding interruption of the vascular supply to the thalamus and optic tract. There was extensive loss of ganglion cells in the central retina, corresponding to the central 10 degrees of vision. As the cortical lesion was too small to affect the thalamus or optic tract directly, the retinal degeneration must be transneuronal. Quantitative analysis showed a 65-80% loss of ganglion cells in the corresponding perifoveal retinae along the horizontal meridian. The results confirm that the loss of retinal ganglion cells following striate cortical lesions is predominantly transneuronal.

Auditory Cortex Signs of Age-Related Hearing Loss

“…Noise and lesion induced cochlear damage produces downstream changes in morphology throughout the rat and cat auditory systems (Powell and Erulkar 1962;Groschel et al 2010;Coordes et al 2012) and causes changes in tonotopic representation in macaque cortex (Rajan and Irvine 1998;Kakigi et al 2000). This type of damage is similar to transsynaptic degeneration effects observed in the visual system (Minkowski 1913;Johnson and Cowey 2000;Zikou et al 2012). The elevated CSF in auditory cortex among people with high frequency hearing loss (Fig.…”

Cerebral gray matter volume reduction in subcortical vascular mild cognitive impairment patients and subcortical vascular dementia patients, and its relation with cognitive deficits

“…Transneuronal degenerations may happen subsequently after the damage of axon in brain (Ginsberg & Martin, 2002;Johnson & Cowey, 2000) and result in cortical atrophy and cognitive impairments.…”

Transsynaptic Retinal Degeneration in Optic Neuropathies: Optical Coherence Tomography Study

“…19,20 Similarly, retrograde transsynap- tic changes in RGC after cortical lesions were found in animals and human studies. 21,22 Expansion of transsynaptic changes into the retina, however, remains controversial. Recently a deficit of bipolar cells in the retina of MS patients (identified pathophysiologically) has been suggested as possible evidence of transsynaptic retinal degeneration.…”