FINAL EXAMS approach as winter draws near. The library swarms with students competing for vacant seats. Students stay up for many nights in a row as they frantically cram for exams. However, studies on the multi-store model of memory demonstrate that cramming won’t help. In fact, it would be better for students not to study at all rather than cram during an exam period; trying to digest a whole semester’s worth of materials will only result in memory deterioration from stress. This month’s Lightbulb will explore the biological nature of the memory system, which proves that excessive studying during exam periods may not be very effective.
Multi-store model of memory
The Multi-store model of memory is one of the theories that explain the memory system. It was first developed by Richard C. Atkinson and Richard M. Shiffrin in 1968. This model has served as the foundational theory to test out subsequent theories of the memory system. The multi-store model of memory states that there are several storages of memory that serve different functions in the process of memorization, taking on a serial order.
Primarily, the sensory organs take in certain information, the process of which is called sensory input. Sensory input is stored in the sensory memory for about 1 to 4 seconds. If the input information is given selective attention, it then moves on to short-term memory, which also has limited space and time. Short-term memory lasts for about 6 to 12 seconds.
When short-term memory is continuously rehearsed, it gets transferred into long-term memory. If the information is not rehearsed, it is discarded. The process of transferring short-term memory into long-term is called encoding, while the reverse process of bringing long-term memory into short-term memory—that is, retrieving an item from long-term memory—is called free recall. Long-term memory has potentially unlimited storage space and indefinite storing time, and thus may also be forgotten with time. In effect, the multi-store model of memory explains that people must repeat wanted information if they are to remember it.
Multi-store model of memory as a theory of cognitive functions proves that memory transfers to long-term memory only through repetition. Cramming limits the time available for sufficient repetition and transfer into long-term memory.
Serial position effect and cramming
There are many studies that back up the multi-store model of memory. Research on the serial position effect, one of the most well known evidential studies, examines how primacy and recency effect support the idea of the multi-store model of memory. The serial position effect implies that people remember the first (primacy effect) and last (recency effect) information that they perceive better than the rest.
A 1962 study by Murdock and a 1966 study by Glanzer and Cunitz proved the existence of primacy and recency effects. The study by Glanzer and Cunitz, which is more widely known, was a controlled laboratory experiment whose aim was to investigate the recency effect. Participants in this experiment were shown a list of items and were immediately instructed to recall them in any order. When Glanzer and Cunitz analyzed the results, they found out that participants tended to better recall the words that were at the beginning and the end of the list. The findings, when plotted on a graph, showed a U-shaped curve, indicating the primacy and recency effects. If participants were given another task after reading the list, primacy effect mostly disappeared while recency effect remained.
Murdock’s study also yielded similar results. He showed participants a list of words without informing them that they would later be asked to recall the information. When the participants were instructed to recall the words, they showed a tendency to better remember the words at the end of the list, demonstrating the recency effect. The participants also exhibited the primacy effect, but recency effect was more prominent in the result. Primacy effect may occur because participants transfer the first few words into long-term memory by unconsciously repeating them while reading the rest of the words. On the other hand, recency effect may be due to information remaining in short-term memory. Since participants were asked to write down what they remembered immediately after reading the list, the recency effect proved to be more prominent than primacy effect. These studies on serial position effect support the multi-store model of memory by demonstrating that several stores exist in the memory system.
Thus, serial position effect also proves that cramming is impractical because people remember only the items that they have recently acquired. In addition, this recency effect only lasts for about 6 to 12 seconds because recently registered information which has not been repeated only remains in short-term memory. Students should thus review the materials they learn from class on a regular basis in order to safely move them to long-term memory.
Stress inhibits memory recall
Many people experience forgetting simple things after many nights of staying awake or after working long hours. As such, stress can have deteriorating effects on memory. When people are stressed out, their adrenal glands secrete a stress hormone called cortisol. Too much cortisol may impede the brain from forming new memories or recalling already formed memories. A low level of stress may reinforce memory encoding and enhance learning experience, but these effects are reversed when the level becomes too high.
Many experimental studies have been carried out to prove the damaging effects of cortisol on memory. Psychologist and author Lars Schwabe conducted an experiment in 2008 on 48 healthy individuals. The participants were divided into two groups, where one was exposed to stress and the other to a control condition while learning both emotional and neutral words. They were asked to recall the words 24 hours after they first learned them. The results revealed that stress worsens the processes of encoding and free recall. Participants who were exposed to stressful situations during the learning process exhibited lower scores than participants in the control group.
Judging from these findings, a high level of stress before exams can hinder memory retrieval and result in an underachieving outcome. Thus, students should relieve stress during exam periods with adequate amount of rest. Cramming induces high levels of stress, which only causes students to forget more easily. Rather than cramming, students should cultivate a habit of studying in advance under low-stress conditions, which can eventually facilitate encoding from short-term memory into long-term memory.
* * *
The multi-store model of memory ultimately illustrates that students should study constantly throughout the semester rather than cram during exam periods. According to the model, students efficiently remember information when they move it to long-term memory through repetition. Serial position effect proves that cramming is ineffective, since recently registered information stays in short-term memory store for only 6 to 12 seconds and is therefore soon lost. Lastly, students should make sure not to get stressed by cramming because stress worsens encoding and recalling abilities. The obvious secret to raising GPA is all in the memory system: study before and play after!