Editing Amygdala (section)

===Memory modulation===
The amygdala is also involved in the modulation of [[memory consolidation]]. Following any learning event, the [[long-term memory]] for the event is not formed instantaneously. Rather, information regarding the event is slowly assimilated into long-term (potentially lifelong) storage over time, possibly via [[long-term potentiation]]. Recent studies suggest that the amygdala regulates memory consolidation in other brain regions. Also, [[fear conditioning]], a type of memory that is impaired following amygdala damage, is mediated in part by long-term potentiation.<ref name="Maren 561–7"/><ref name="ReferenceA"/> During the consolidation period, the memory can be modulated. In particular, it appears that emotional arousal following the learning event influences the strength of the subsequent memory for that event. Greater emotional arousal following a learning event enhances a person's retention of that event. Experiments have shown that administration of [[stress hormones]] to mice immediately after they learn something enhances their retention when they are tested two days later.<ref>"Researchers Prove A Single Memory Is Processed in Three Separate Parts of the Brain" {{cite web |url=https://www.sciencedaily.com/releases/2006/02/060202182107.htm |title=Researchers Prove a Single Memory is Processed in Three Separate Parts of the Brain |access-date=2018-02-28 |url-status=live |archive-url=https://web.archive.org/web/20170912055423/https://www.sciencedaily.com/releases/2006/02/060202182107.htm |archive-date=12 September 2017}}</ref>

The amygdala, especially the basolateral nuclei, are involved in mediating the effects of emotional arousal on the strength of the memory for the event, as shown by many laboratories including that of [[James McGaugh]]. These laboratories have trained animals on a variety of learning tasks and found that drugs injected into the amygdala after training affect the animals' subsequent retention of the task. These tasks include basic [[classical conditioning]] tasks such as inhibitory avoidance, where a rat learns to associate a mild footshock with a particular compartment of an apparatus, and more complex tasks such as spatial or cued water maze, where a rat learns to swim to a platform to escape the water. If a drug that activates the amygdalae is injected into the amygdalae, the animals had better memory for the training in the task.<ref>{{cite journal | vauthors = Ferry B, Roozendaal B, McGaugh JL | s2cid = 36848472 | title = Role of norepinephrine in mediating stress hormone regulation of long-term memory storage: a critical involvement of the amygdala | journal = Biological Psychiatry | volume = 46 | issue = 9 | pages = 1140–52 | date = November 1999 | pmid = 10560021 | doi = 10.1016/S0006-3223(99)00157-2 }}</ref>

Amygdala activity at the time of encoding information correlates with retention for that information. However, this correlation depends on the relative "emotionalness" of the information. More emotionally arousing information increases amygdalar activity, and that activity correlates with retention. Amygdala neurons show various types of [[Neural oscillation|oscillation]] during emotional arousal, such as [[Theta rhythm|theta activity]]. These synchronized neuronal events could promote [[synaptic plasticity]] (which is involved in memory retention) by increasing interactions between neocortical storage sites and temporal lobe structures involved in [[declarative memory]].<ref>{{cite journal |vauthors=Paré D, Collins DR, Pelletier JG |date=July 2002 |title=Amygdala oscillations and the consolidation of emotional memories |journal=Trends in Cognitive Sciences |volume=6 |issue=7 |pages=306–314 |doi=10.1016/S1364-6613(02)01924-1 |pmid=12110364 |s2cid=10421580}}</ref>

In rats, [[DNA damage (naturally occurring)|DNA damage]] was found to increase in the amygdala immediately after exposure to stress.<ref name="pmid20226828">{{cite journal |vauthors=Consiglio AR, Ramos AL, Henriques JA, Picada JN |s2cid=38959073 |title=DNA brain damage after stress in rats |journal=Prog. Neuropsychopharmacol. Biol. Psychiatry |volume=34 |issue=4 |pages=652–6 |date=May 2010 |pmid=20226828 |doi=10.1016/j.pnpbp.2010.03.004 |doi-access=free }}</ref> Stress was induced by 30 minutes of restraint or by forced swimming. By seven days after exposure to these stresses, increased DNA damage was no longer detectable in the amygdala, probably because of [[DNA repair]].<ref name="pmid20226828" />

[[Buddhist monks]] who do [[Maitrī|compassion meditation]] have been shown to modulate their amygdala, along with their [[temporoparietal junction]] and [[Insular cortex|insula]], during their practice.<ref>{{cite web | title = Cultivating compassion: Neuroscientific and behavioral approaches | first = Richard J. | last = Davidson | name-list-style = vanc | url = http://ccare.stanford.edu/node/25  |access-date=2010-07-04 |url-status=dead |archive-url=https://web.archive.org/web/20100714174906/http://ccare.stanford.edu/node/25 |archive-date=14 July 2010}}</ref> In an [[Functional magnetic resonance imaging|fMRI]] study, more intensive insula activity was found in expert meditators than in novices.<ref>{{cite journal | vauthors = Lutz A, Brefczynski-Lewis J, Johnstone T, Davidson RJ | title = Regulation of the neural circuitry of emotion by compassion meditation: effects of meditative expertise | journal = PLOS ONE | volume = 3 | issue = 3 | pages = e1897 | date = March 2008 | pmid = 18365029 | pmc = 2267490 | doi = 10.1371/journal.pone.0001897 | veditors = Baune B | bibcode = 2008PLoSO...3.1897L | doi-access = free }}</ref>

[[File:Rorschach blot 03.jpg|thumb|[[Rorschach test]] blot 03]]

Research using [[Rorschach test]] blot 03 finds that the number of unique responses to this random figure links to larger sized amygdalae. The researchers note, "Since previous reports have indicated that unique responses were observed at higher frequency in the artistic population than in the nonartistic normal population, this positive correlation suggests that amygdalar enlargement in the normal population might be related to creative mental activity."<ref>{{cite journal | vauthors = Asari T, Konishi S, Jimura K, Chikazoe J, Nakamura N, Miyashita Y | s2cid = 30109156 | title = Amygdalar enlargement associated with unique perception | journal = Cortex; A Journal Devoted to the Study of the Nervous System and Behavior | volume = 46 | issue = 1 | pages = 94–9 | date = January 2010 | pmid = 18922517 | doi = 10.1016/j.cortex.2008.08.001 }}</ref>