An increasing number of studies show that memory allows people to engage in a form of mental time travel. Through this process, we can not only recreate past situations but also depict the future. The research also indicates that beyond helping us store and recall information about events that have already occurred, the existence of memory has broader significance.
In recording and analyzing how memory helps us outline someone's personality traits and predict their possible performance in future social situations, researchers from University College London and Harvard University have made certain progress. Last week, the researchers elaborated on their latest scientific findings published in the journal Cerebral Cortex.
The insights revealed by these researchers may affect not only amnesiac patients, such as the elderly, but also young people and their planning and social skills. Researchers are continuing to explore existing scientific conclusions, trying to understand whether the ability to reminisce is related to creativity and imagination.
Harvard University psychology professor Daniel Schacter stated that the main body of the research paper "has expanded our horizons on how to use memory."
This imagination or foresight of the unknown world is not only crucial for our planning and problem-solving abilities but also helps us make better decisions in social situations. At the same time, researchers hope to reveal new ways to enhance human memory. Schacter also noted that "predicting what might happen in the future based on past experiences" allows people to avoid having to try everything in reality; they only need to carefully consider events similar to future situations.
Why might some people naturally have a stronger ability to recall the past or envision the unknown? Currently, people know very little about this question.
Many methods claimed to improve memory and delay cognitive decline, such as crossword puzzles and brain teasers, focus primarily on working memory, i.e., the information we keep in our minds at any given time. Regarding whether working memory has more functions beyond improving the ability to complete specific tasks, there are various pieces of evidence and claims.
Dr. Schacter's team focused on targeted interventions for recalling past experiences, known as episodic memory. They also focused on increasing the ability to recall details, rather than overall memory improvement. The preliminary trials of this study are expected to be completed this summer.
Talking to patients with amnesia first conveyed a message to researchers: recalling past experiences may be crucial for mental time travel. Like amnesiac patients, patients with amnesia both struggle when making plans. Dr. Schacter and his graduate advisor Endel Tulving began observing patient K.C. in the 1980s. For example, when asked what he would do the next day, K.C. could not give a detailed answer. Dr. Schacter said K.C. might say something like "I think I'm going to have breakfast," but could not provide any relevant details, such as what he might eat or where he would go to eat.
In 2007, researchers from the Gatsby Computational Neuroscience Unit at University College London, including Demis Hassabis and his colleagues, published a study in the Proceedings of the National Academy of Sciences showing that five amnesiac patients exhibited extremely limited abilities when imagining and describing future events. This finding caused a stir in the field and spurred further research.
Since then, scientists have conducted many studies in the laboratory, all indicating that healthy young adults perform better than elderly people with declining memory in imagining future scenarios. Schizophrenic patients who struggle to recall the past also face difficulties in depicting the future. Dr. Schacter said that in research conducted by him and his colleagues, when people around 70 to 75 years old were asked about the past or the future, they tended to provide more comments and insights, but offered little regarding character details or exactly what happened. For example,
when young people were asked about a shopping trip, they would mention who went there and the details of the shops.
Whereas elderly people would talk about their interest in buying vases and why having vases at home would be nice.
Brain imaging studies have shown that, just like recalling the past, when people are asked to imagine the future, many of the same regions in their brains—specifically the hippocampus and the medial prefrontal cortex—show signs of increased activity. These are also the regions most likely to change as people age. The ability to imagine detailed simulated scenarios seems quite useful. This ability helps people make plans by using imagination to model different possibilities without having to implement them one by one. Quickly previewing a series of hypothetical scenarios in the mind is expected to guide us to make better choices.
Researchers at the University of California, Los Angeles found that students who carefully simulated the details of exam review—i.e., imagining all the steps involved in the learning process—ultimately scored higher than those who only imagined themselves doing well on the exam.
Memory also seems to play a role in experiencing and imagining the feelings of others in the present, which is known as theory of mind. This helps people judge how to regulate their behavior in unfamiliar social situations, such as when meeting a group of new friends or starting a new job. Patients with autism often have poor episodic memory and a low ability to predict others' reactions or emotions. Poor social skills are one of the symptoms of autism.
Currently, people know very little about how the brain operates when people try to figure out what others are thinking. Dr. Hassabis, Dr. Schacter, and their collaborators explored this question in their new study. They scanned the brains of 19 healthy adults with an average age of 21. During the scanning process, the doctors asked these young people to imagine four short scenes, including fictional characters.
First, participants were given some photos and 12 personal profiles for these four characters. Each character had different levels of extroversion and friendliness. After spending some time familiarizing themselves with these fabricated character profiles, participants were asked to imagine each different character in various situations. For example: How would each of them react if a stranger spilled drinks on them?
Researchers found that the ability to distinguish different personality traits is encoded in vastly different brain regions. This means that when participants imagine a scene, researchers can determine which of the four characters the participant is imagining at that moment simply by looking at which area of the brain shows higher activity.
For imagining future events, the episodic memory system does not appear to be the only important brain process. Arnaud D'Argembeau, a researcher at the University of Liège in Belgium, believes that autobiographical memory in a broad sense, including episodic memory, can be used to organize and construct events. D'Argembeau's writings have shown that knowing someone's personal goals—memory is necessary for this—seems to be another factor that helps imagine future events.
The ability to simulate and imagine events in someone's mind can also bring potential negative effects. If we cannot predict all possible occurrences, or if we become overconfident in thinking we have predicted what will happen, this ability can cause trouble.
In worse cases, anticipating the outcome of the future, especially negative outcomes, may make it harder for the elderly to make plans, or make them feel that someone might be trying to take advantage of them. Dr. Schacter said, "It puts a different lens on you; through it, you see yourself aging."
Comment: This view may corroborate the saying in Chapter 2 of Guiguzi: "The great transformers of antiquity were born with the formless. Looking back at the past, they verified the future; looking back at the ancient, they knew the present; looking back at the other, they knew this. If the principles of movement and stillness, emptiness and fullness do not align with the present, look back to the ancient to seek answers. There are things that return to their origin through reversal; this is the intent of the sage, which must not be overlooked." For a detailed explanation of this chapter, see:
Guiguzi Reaction Chapter Two