P ROTEIN S YNTHESIS M AKES M EMORIES Kellie Howard

T YPES OF M EMORIES Also known as primary/active memory Commonly lasts seconds “The Magic Number Seven, Plus or Minus Two” Precursor to memories being consolidated in long – term memory Also known as our unconscious memory Can last days, months, or a lifetime Continuous storage of information Formed by reoccurring association and rehearsal Two groups: Explicit and Implicit Short-TermLong-Term

M AKING M EMORIES Long-Term and Short-Term memories come from connections between neurons called “synapses”. Memories are made when the synapses is stimulated For this stimulation to occur the nucleus must be activated and proteins produced

CREB AND M EMORY Mid 90’s found CREB plays an important role in transcription of short-term memories to long-term More recent research shows: CREB keeps memories stable Amount of CREB directly influences memory storage in the brain Cell CREB low  Less likely to store a memory Cell CREB high  More likely to store a memory CREB may have therapeutic potentials for Alzheimer's patients

P ROCESS Step 1: A strong stimulation depolarizes the cell membrane Multiple firing of a single synapse Simultaneous firings from multiple synapses “All or None” Law Not all incoming stimuli are strong enough to cause a nerve to fire – MUST STIMULATE PAST THRESHOLD (-30mV) Sodium channels open – depolarization (inside) Potassium channels open – repolarization (outside) Resting concentration restored

P ROCESS Step 2: When the incoming signal is strong enough the neuron fires Step 3: Once depolarized, voltage-sensitive calcium channels in the body of the neuron open Step 4: There is an influx of calcium in the neuron and this calcium activates enzymes that will in turn activate CREB

P ROCESS Step 5: CREB activates the genes for synapse-strengthening proteins Step 6: These proteins diffuse throughout the cell but only affect the synapses that were strengthened

O VERVIEW Synaptic consolidation Occurs within the first few hours after learning System consolidation Hippocampus dependent memories become independent of the hippocampus over weeks or years More synapse strength = more signals between neurons Neurons fire together often and become sensitized to one another This creates more pathways in the brain as new experiences build up – “re-wire”

R EFERENCES Alcino, S. (2007, April 20). Protein called CREB key to memory storage in brain. In News: Medical. Retrieved March 20, 2012 Campbell, M. K., & Farrell, S. O. (2012). Biochemistry (7th ed., p. 344). N.p.: Brooks/Cole. Cherry, K. (2012). What is Long Term Memory?. In AskAbout.com Psychology. Retrieved March 18, 2012 Cowan, N. (2001). The magical number 4 in short-term memory: A reconsideration of mental storage capacity. Behavioral and Brain Sciences, 2, 97–185. Miller, G. A. (1956). The magical number seven, plus or minus two: Some limits on our capacity for processing information. Psychological Review, 63, 81–97.