  Perceptual hallucinations are present in neurological and psychiatric
disorders and amputees. While the hallucinations can be drug-induced, it has
been described that they can even be provoked in healthy subjects.
Understanding their manifestation could thus unveil how the brain processes
sensory information and might evidence the generative nature of perception. In
this work, we investigate the generation of tactile hallucinations on
biologically inspired, artificial skin. To model tactile hallucinations, we
apply homeostasis, a change in the excitability of neurons during sensory
deprivation, in a Deep Boltzmann Machine (DBM). We find that homeostasis
prompts hallucinations of previously learned patterns on the artificial skin in
the absence of sensory input. Moreover, we show that homeostasis is capable of
inducing the formation of meaningful latent representations in a DBM and that
it significantly increases the quality of the reconstruction of these latent
states. Through this, our work provides a possible explanation for the nature
of tactile hallucinations and highlights homeostatic processes as a potential
underlying mechanism.
