Editing Episodic memory (section)

==Cognitive neuroscience==
The formation of new episodic memories requires the [[medial temporal lobe]], a structure that includes the [[hippocampus]]. Without the medial temporal lobe, one is able to form new [[procedural memory|procedural memories]] (such as playing the piano) but cannot remember the events during which they happened (See [[Hippocampus#Role in general memory|the hippocampus and memory]]).

The [[prefrontal cortex]] (and in particular the [[right hemisphere]]) is also involved in the formation of new episodic memories (also known as episodic encoding). Patients with damage to the prefrontal cortex can learn new information, but tend to do so in a disordered fashion. For example, they might show normal [[Recall (memory)|recognition]] of an object they had seen in the past, but fail to [[source amnesia|recollect]] when or where it had been viewed.<ref>{{cite journal | vauthors = Janowsky JS, Shimamura AP, Squire LR | title = Source memory impairment in patients with frontal lobe lesions | journal = Neuropsychologia | volume = 27 | issue = 8 | pages = 1043–56 | year = 1989 | pmid = 2797412 | doi = 10.1016/0028-3932(89)90184-X | s2cid = 29293288 }}</ref> Some researchers believe that the prefrontal cortex helps organize information for more efficient storage, drawing upon its role in [[executive function]]. Others believe that the prefrontal cortex underlies [[semantic]] strategies which enhance encoding, such as thinking about the meaning of the study material or rehearsing it in [[working memory]].<ref>{{cite journal | vauthors = Gabrieli JD, Poldrack RA, Desmond JE | title = The role of left prefrontal cortex in language and memory | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 95 | issue = 3 | pages = 906–13 | date = February 1998 | pmid = 9448258 | pmc = 33815 | doi = 10.1073/pnas.95.3.906 | bibcode = 1998PNAS...95..906G | doi-access = free }}</ref>

Other work has shown that portions of the inferior [[parietal lobe]] play a role in episodic memory, potentially acting as an accumulator to support the subjective feeling that something is "old", or perhaps supporting mental imagery which allows you a sense of the vividness of memories.  Indeed, bilateral damage to the inferior parietal lobe results in episodic memory that is largely intact, however it lacks details <ref name="Berryhill">{{cite journal |last1=Berryhill |first1=M.E. |last2=Picasso |first2=L. |last3=Phuong |first3=L. |last4=Cabeza |first4=R. |last5=Olson |first5=I.R. |title=Parietal lobe and episodic memory: bilateral damage causes impaired free recall of autobiographical memory |journal=Journal of Neuroscience |date=2007 |volume=27 |issue=52 |pages=14415–23 |doi=10.1523/JNEUROSCI.4163-07.2007 |pmid=18160649 |pmc=6673454 }}</ref> and lesion patients report low levels of confidence in their memories.<ref name="Hower">{{cite journal |last1=Hower, K. |first1=Wixted, J. |last2=Berryhill, M.E. |first2=Olson, I.R. |title=Impaired perception of mnemonic oldness, but not mnemonic newness, after parietal lobe damage |journal=Neuropsychologia |date=2014 |volume=56 |pages=409–17 |doi=10.1016/j.neuropsychologia.2014.02.014 |pmid=24565734 |pmc=4075961 }}</ref>

Researchers do not agree about how long episodic memories are stored in the hippocampus. Some researchers believe that episodic memories always rely on the hippocampus. Others believe the hippocampus only stores episodic memories for a short time, after which the [[memory consolidation|memories are consolidated]] to the [[neocortex]]. The latter view is strengthened by recent evidence that [[neurogenesis]] in the adult hippocampus may ease the removal of old memories and increase the efficiency of forming new memories.<ref>{{cite journal | vauthors = Deisseroth K, Singla S, Toda H, Monje M, Palmer TD, Malenka RC | title = Excitation-neurogenesis coupling in adult neural stem/progenitor cells | journal = Neuron | volume = 42 | issue = 4 | pages = 535–52 | date = May 2004 | pmid = 15157417 | doi = 10.1016/S0896-6273(04)00266-1 | s2cid = 9210805 | doi-access = free }}</ref>