Many individuals have found that cramming for an exam doesn’t work all that well, which seemed contradictory to a commonly accepted theory that learning is cumulative, with synapses starting very small and then getting larger and stronger. Recent study results at Carnegie Mellon University may have provided a possible explanation. It is fairly well established that brain connections between neurons and other cells (synapses) that allow for the transmission of information, grow when they’re exposed to a stimulus. Research by Professor of Biological Sciences, Alison L. Barth, has not only confirmed this but also revealed that synapses get even stronger than previously thought. However, it also showed that synapses quickly go through a transitional phase where they weaken. The neuroscientists identified three distinct phases that synapses go through on the first day of learning:
1. Initiation phase (e.g., over the next 12 hours or so) - the synapses get stronger and stronger.
2. Labile phase – as the stimulus is repeated, the synapses weaken.
3. Stabilization phase – after a few hours of weakening, the synapses maintain their residual strength.
“Based on our data, it seems like synapses that have recently been strengthened are peculiarly vulnerable—more stimulation can actually wipe out the effects of learning,” said Barth. Because of this synaptic fragility right after plasticity, more training is actually counterproductive. For long-lasting memory, spaced training (e.g., studying for your classes after every lecture, all semester long) is superior to cramming all night before the exam.