Cellular Mechanisms

• 150 trillion synapses in the human brain
• The human brain stops gaining weight after 10 years old, but we still find ways of making new memories
• Jennifer Aniston neurons or concept cells


  Cortical neurons in the temporal lobe that react to highly specific stimuli like Star Wars related things
• Encoding


  The ability of the brain circuits to store pieces of information
• Consolidation


  "cells that fire together wire together," the idea that memories get stored in synapses that strengthen or weaken depending on how often they are used
• Memory trace (engram)


  Specific circuit of neurons that represnts a specific encoded piece of information (neurons firing together in a pattern = a memory)
• Reverberation


  Process by which networks of neurons fire repeatedly. Each time the circuit is activated it gets stronger, making it easier to happen again in the future when it's reactivated
• Memories seem to be kept in the hippocampus an amygdala for a certain amount of time before being stored more permanently in the cortex. It might have been 2 years but because HM is our source and he was messed from epilepsy we cant know for sure
• Retrieval


  When stored memories (engrams) are recalled and reconsolidated to remember them. Sometimes "false memories" happen because these circuits aren't 100% exact and often exaggerate aspects based on our emotions ("happy" memories leave out the bad parts and "bad" memories exaggerate the bad parts while dampening the good)
• Place cells


  Special population of pyramidal cells in the hippocampus that increase their firing when an animal is in a particular place or environment. Not topical (organized in the brain based on their organization irl)
• Grid cells


  Located at the entorhinal cortex, the main HPC input structure. Fire when an animal is at an intersection in a previously explored environment. The "this" is made up of overlapping hexagons which combine to create an idea of your surroundings