This is attributed to them perceiving a ringing in the ear during those gaps.
![auditory illusions auditory illusions](https://i.ytimg.com/vi/-aWXNOtk-oA/hqdefault.jpg)
The hypothesis is that animals with tinnitus have worse gap detection thresholds compared to controls. The presence of tinnitus is screened by the ability of the animal to detect gaps embedded into a continuous stream of noise (Turner et al., 2006). Animals are subjected to a blast of loud noise that produces noise-induced hearing loss. Inducing tinnitus in humans has its ethical issues and hence researchers have relied instead on animal models (Dehmel, Eisinger, & Shore, 2012 Jastreboff, Sasaki, & Brennan, 1988 Noreña, 2011 Wang, Brozoski, & Caspary, 2011). However, the acute phase of tinnitus has received relatively little attention. Chronic tinnitus is widely studied in humans using neuroimaging, electrophysiological, and both invasive and noninvasive neuromodulation techniques (Claes, Stamberger, Van de Heyning, De Ridder, & Vanneste, 2014 De Ridder, Congedo, & Vanneste, 2015 De Ridder & Vanneste, 2014 Hullfish, Abenes, Yoo, De Ridder, & Vanneste, 2019 Hullfish et al., 2018a, 2018b Husain et al., 2011 Mohan, Alexandra, Johnson, De Ridder, & Vanneste, 2018 Mohan, De Ridder, Idiculla, DSouza, & Vanneste, 2018 Mohan, De Ridder, & Vanneste, 2016, 2017). Tinnitus can be a debilitating disorder commonly accompanied by noise-related or age-related hearing loss (König, Schaette, Kempter, & Gross, 2006 Negri & Schorn, 1991 Peelle & Wingfield, 2016) affecting several million people all over the world.
![auditory illusions auditory illusions](https://www.dowtechnologies.com/img/product/C10~6-Z.jpg)
Tinnitus is the simplest kind of auditory phantom perception, where people report a ringing or buzzing in their ear (Jastreboff, 1990). This compensation for decreased input can manifest as the perception of the expected but missing stimulus in that specific sensory domain, called phantom perception (Mohan & Vanneste, 2017). In the event of decreased bottom-up input, the brain finds alternate mechanisms to compensate for the change in incoming information relying more on top-down factors such as memory and cues from other sensory modalities, thus modifying perception (Friston, 2010 Mohan & Vanneste, 2017). Perception is a top-down process for interpreting the nature and meaning of bottom-up sensory stimuli (Schacter, 2011). This could inform us if the ZT illusion may be a precursor to chronic tinnitus. To establish a more concrete relationship between ZT illusion and chronic tinnitus, future longitudinal studies following up a much larger sample of participants who reliably perceive a ZT illusion to see if they develop tinnitus at a later stage is essential. It could also suggest a successful retrieval of the memory of the missing frequencies, resulting in their conscious perception indicating the role of higher-order processing in the mechanism of action of ZT illusions. Such changes may suggest a malfunction of the sensory gating system that enables habituation to redundant stimuli and suppresses hyperactivity. Furthermore, we observe that increased theta power significantly predicts a gradual positive change in the intensity of the ZT illusion. We observed changes in evoked and total theta power in wide-spread regions of the brain particularly in the temporal-parietal junction, pregenual anterior cingulate cortex/ventromedial prefrontal cortex (pgACC/vmPFC), parahippocampus during perception of the ZT illusion.
![auditory illusions auditory illusions](https://i.ytimg.com/vi/wUUIkIhEWQY/maxresdefault.jpg)
In the current study, we compared the neural correlates of the reliable perception of a ZT illusion to that which is not. ZT illusions are perceived following the presentation of a notched noise stimulus, that is, broadband noise with a narrow band-stop filter (notch). Past studies have established Zwicker tone (ZT) illusions as a good human model for acute tinnitus. However, we still do not understand what happens in the acute phase. Several studies have demonstrated the neural correlates of chronic tinnitus.