“…This is consistent with boredom, but also with other explanations, including apathy, depression, or cognitive impairment. Taking a different approach, monotony causes many species to seek novelty, even novel stimuli they would normally avoid (reviewed in Berlyne, 1960;Kirkden, 2000;Mason et al, 2013;Stevenson, 1983). For example, despite normally shunning bright light, rats (Rattus norvegicus) increasingly pressed levers for flashes of light the longer they were kept in darkness (in Berlyne, 1960).…”