Editing Perception (section)

==== Familiarity ====

[[Recognition memory]] is sometimes divided into two functions by neuroscientists: ''familiarity'' and ''recollection''.<ref>{{cite journal|last=Mandler|year=1980|title=Recognizing: the judgement of prior occurrence|url=http://www.escholarship.org/uc/item/58b2c2fc|journal=Psychological Review|volume=87|issue=3|pages=252–271|doi=10.1037/0033-295X.87.3.252|s2cid=2166238 }}</ref> A strong sense of familiarity can occur without any recollection, for example in cases of [[deja vu]].

The [[temporal lobe]] (specifically the [[perirhinal cortex]]) responds differently to stimuli that feel novel compared to stimuli that feel familiar. [[Firing rate (cells)|Firing rates]] in the perirhinal cortex are connected with the sense of familiarity in humans and other mammals. In tests, stimulating this area at 10–15&nbsp;Hz caused animals to treat even novel images as familiar, and stimulation at 30–40&nbsp;Hz caused novel images to be partially treated as familiar.<ref>{{cite journal|vauthors=Ho JW, Poeta DL, Jacobson TK, Zolnik TA, Neske GT, Connors BW, Burwell RD|date=September 2015|title=Bidirectional Modulation of Recognition Memory|journal=The Journal of Neuroscience|volume=35|issue=39|pages=13323–35|doi=10.1523/JNEUROSCI.2278-15.2015|pmc=4588607|pmid=26424881}}</ref> In particular, stimulation at 30–40&nbsp;Hz led to animals looking at a familiar image for longer periods, as they would for an unfamiliar one, though it did not lead to the same exploration behavior normally associated with novelty.

Recent studies on [[lesion]]s in the area concluded that rats with a damaged perirhinal cortex were still more interested in exploring when novel objects were present, but seemed unable to tell novel objects from familiar ones—they examined both equally. Thus, other brain regions are involved with noticing unfamiliarity, while the perirhinal cortex is needed to associate the feeling with a specific source.<ref>{{cite journal|vauthors=Kinnavane L, Amin E, Olarte-Sánchez CM, Aggleton JP|date=November 2016|title=Detecting and discriminating novel objects: The impact of perirhinal cortex disconnection on hippocampal activity patterns|journal=Hippocampus|volume=26|issue=11|pages=1393–1413|doi=10.1002/hipo.22615|pmc=5082501|pmid=27398938}}</ref>