Increases in spontaneous neural activity in the hamster dorsal cochlear nucleus following cisplatin treatment: a possible basis for cisplatin-induced tinnitus

Tinnitus as a plastic phenomenon and its possible neural underpinnings in the dorsal cochlear nucleus

“…They investigated the relationship between hyperactivity and hair cell loss using the ototoxic agent, cisplatin. When systematically administered to hamsters at doses between 1.5 and 3.0 mg/kg, this drug causes both cochlear hair cell loss and increases in spontaneous activity in the DCN (Melamed et al, 2000;Rachel et al, 2002). The magnitudes of the increases were found to vary considerably across subjects as were the severities of the hair cell lesions.…”

Insult-induced adaptive plasticity of the auditory system

“…This activity change mirrors those seen in the response profiles of fusiform cells (Caspary et al, 2005) and glycinergic cartwheel cells (Caspary et al, 2006) during presbyacusis onset in rats. Although amplified responses may be derived from systemic inhibitory dysfunction (Middleton et al, 2011), the existence of a correlation between OHC disruption and DCN spontaneous discharge indicates that the onset of hyperactivity within the DCN is probably the result of a confluence of factors (Kaltenbach et al, 2002; Rachel et al, 2002). …”

Salicylate induced tinnitus: Behavioral measures and neural activity in auditory cortex of awake rats

“…Since the biological mechanisms that give rise to tinnitus are still poorly understood, acoustic overstimulation and ototoxic drugs are typically used to try to induce tinnitus in animal models in order to study its neural correlates. Because there are individual differences in susceptibility to noise or drug induced tinnitus, it is important to employ behavioral techniques that permit tinnitus to be Abbreviations: SIPAC, schedule induced polydipsia avoidance conditioning; GPIAS, gap pre-pulse inhibition of acoustic startle; NBPIAS, noise burst pre-pulse inhibition of acoustic startle; AC, auditory cortex; STng, startle reflex recorded without a gap pre-pulse stimulus; STg, startle reflex recorded with a gap pre-pulse stimulus; STq, startle reflex recorded without a pre-pulse stimulus; STnb, startle reflex recorded with a noise burst pre-pulse stimulus assessed in individual animals treated with a particular tinnitus inducing agent in order to determine if tinnitus is present or absent at a particular time (Guitton et al, 2003;Heffner and Harrington, 2002;Kaltenbach et al, 2002;Lobarinas et al, 2004;Rachel et al, 2002).…”