Biological Advances into Memory Modification and Recall
In 2012, a famous movie “ Total Recall“ was re-made from the 1990 original American science fiction action thriller movie. In 1966, Phillip K. Dick published a short story called “We can remember it for you wholesale.” In this plot, the setting is in the future, in the year 2084, when a the character Douglas Quaid, a construction worker, suffered from mysterious dreams every night. One day, he came across a company that provided a service that can inject a certain portion of memory into one’s mind, advertised as “Rekal”. Quaid patroned them and had memory injected, and experienced being on Mars as if he had experienced it in his own life.
The general public might think that this is only possible in the movie or in the distant future (Y 2084). However, in reality, a research team led by professor Jin-Hee Han at KAIST reported that a substance or chemical can be injected into the mouse brain to induce recall artificially or make modifications of specific memory in the absence of any behavioural cues (Kim et al., Nature Neuroscience 2014). It has been reported that neurons with higher level of CREB than their neighbours (CREB = cAMP/Ca2+ response element binding protein) are selected to be included into memory engram during memory formation. Inspired by this finding, the CREB gene was injected into small number of cells in the mouse amygdala, a brain area responsible for fear. Surprisingly, simply injecting the drug that stimulated only CREB cells was sufficient to activate recall of that learned memory. Moreover, the same procedure was also able to modify the established memory. This was laboratory work carried out by the leading author Jieun Kim.
Figure 1. Drug-mediated control of CREB cells in the mouse brain.
Figure 2. Activating CREB cells in the mouse brain after learning-induced recall of that specific fear memory.
This research finding constitutes some of the first evidence to support that artificial recall or modifications of existing memory are possible.
NOTE: Recently the Defence Advanced Research Project Agency (DARPA) in America announced that about 4 million dollars would be funded for research that can restore the memory of wounded or disease-inflicted patients. The findings described herein would be a ground breaking technology that can be applied to this biomedical research field.
Related article: Jieun Kim et al. (Memory recall and modifications by activating neurons with elevated CREB. Nature Neuroscience 17(1):65-72, 2014.)