Despite all of the advances made in both medical technology and research, the human body remains the site of much scientific exploration. And such work is often crucial, as our internal organs – from the heart to the lungs and the liver – all play an integral part in our everyday functions. However, there’s one particular part of the body about which we still have much to learn.
Yes, that’s the human brain, which governs every decision and movement that we make – making it arguably the most complicated organ we possess. And perhaps one of the most fascinating things about the brain is the processes by which we make and retrieve memories.
The limbic system is a set of structures located in the midbrain that is responsible for several essential tasks in the human body – such as telling us when we’re hungry or when we’re too hot or cold. And it’s this area of the brain that also plays a role in retaining our memories through an arched configuration known as the hippocampus, which is located near the temporal lobes. But the hippocampus’ job is even more complex than you may initially suspect.
You see, the hippocampus also serves as the link between memories and feelings – a function that many take advantage of day to day. But while not everyone can access certain pieces of information readily, that in turn may say something about an individual. Yes, according to an intriguing study from June 2017, forgetfulness may signify something quite surprising about a person’s brain.
For many of us, memories play a crucial role in our everyday lives. And whether we use what we’ve learned and experienced to recall facts or merely for sentimental value, knowing that these snapshots of the past can be accessed via a simple thought is comforting. It’s perhaps no surprise, then, that the hippocampus has been the focus of many studies over the past 400 years.
And at this point, it’s worth exploring exactly what the hippocampus is. As Dr. Ananya Mandal explained in an article for News-Medical.Net, “The hippocampus is located in the medial temporal lobe of the brain underneath the cortical surface. Its structure is divided into two halves [that] lie in the left and right sides of the brain, [and] the organ [itself] is curved with a shape that resembles a seahorse.”
What’s more, this vital component of the brain has been studied since the 16th century. “The hippocampus was first referred to by Venetian anatomist Julius Caesar Aranzi in 1587,” Mandal continued. “He described it as a ridge along the floor of the temporal horn of the lateral ventricle and likened it first to a silkworm and later to a seahorse.”
But while the hippocampus helps us retain our long-term memories, its function doesn’t end there; recent memories are formed in that area of the brain, too. However, much as is the case with any other organ in the human body, the hippocampus can be affected by illness and various disorders.
Of all those conditions, though, perhaps one is particularly feared. “In diseases such as Alzheimer’s disease, the hippocampus is one of the first regions of the brain to become damaged,” Mandal has explained. “This leads to the memory loss and disorientation associated with the condition.”
And brain function can be affected by other issues, too, as Mandal revealed. “The hippocampus can also become damaged through oxygen deprivation or hypoxia, infection or inflammation,” the physician continued, “or as a result of temporal lobe epilepsy.”
Then there’s yet another ailment that involves the hippocampus, and this sometimes has quite a considerable impact on the ability to recall past events and experiences. “Individuals with hippocampal damage develop amnesia,” Mandal added, “[meaning that] they may be unable to form new memories of the time or location of an event.”
All in all, then, the hippocampus remains a highly important area of the brain as well as one that scientists are still exploring. And Professor Blake Richards is one such researcher, having co-written a paper about memories that was published in June 2017 for the journal Neuron.
Back in 2004 Richards graduated from the University of Toronto with a diploma in cognitive science and artificial intelligence. And after years of undergraduate research, he was keen to continue his studies; in the end, though, another opportunity presented itself.
So, instead of returning to the books, Richards earned a position at Ontario’s Center for Addiction and Mental Health after graduation. And over the two years that followed, he worked as both an analyst and a programmer before leaving in 2006. At that point, the scientist went back to his academic studies.
Yes, in 2007 Richards enrolled at the University of Oxford, where he took part in a Ph.D. program that ran in conjunction with the charity Wellcome Trust. And during that time, he was stationed in the university’s pharmacology department. “I explored synaptic plasticity in early life,” Richards later explained on the LiNC Lab website.
“During the MSc component of the program, I worked with Dr. Wyeth Bair and Dr. Ole Paulsen,” Richards added of his endeavors. “[I was] studying computational models of visual processing and voltage bistability in neocortical dendrites.” To put it simply, he was looking at the on-off functions of the brain’s main synaptic nerve receptors.
Then, after Richards’ time at Oxford came to an end, he continued his studies back in Toronto at The Hospital for Sick Children. And over the course of two years, he gravitated toward the subjects of neural plasticity – the brain’s capacity to shift and adjust – and memory consolidation.
After Richards had concluded his work at the hospital, however, he embarked on yet another prestigious position. “Since January 2014, I have been an assistant professor at the University of Toronto in the Department of Biological Sciences (Scarborough),” the Canadian wrote on LiNC Lab.
Nevertheless, everything is set to change in the summer of 2019. “I have accepted a position in the School of Computer Science and the Montreal Neurological Institute at McGill University,” Richards continued. “I will be starting there in August 2019.”
And Richards has explained why he has taken the career path that he is currently on. “My identity has been tied to science for a long time,” he divulged. “[If I hadn’t gotten into science], I would probably have gone into either the tech sector or policy.”
As a researcher, though, Richards teamed up with University of Toronto colleague Paul Frankland to embark on an in-depth study of memory. And in the process, the pair uncovered some potentially significant information on the subject of forgetfulness, which was later revealed in a paper published in Neuron in 2017.
At the beginning of the report, Richards and Frankland outline the purpose of their work. “The predominant focus in the neurobiological study of memory has been on remembering (persistence),” the introduction reads. “However, recent studies have considered the neurobiology of forgetting (transience).”
And from there, Frankland and Richards revealed that they had come up with a theory that may shed some light on why some individuals are rather forgetful. “Here we draw parallels between neurobiological and computational mechanisms underlying transience,” they wrote. “We propose that it is the interaction between persistence and transience that allows for intelligent decision-making in dynamic, noisy environments.”
Indeed, according to Richards and Frankland, a forgetful person may be more intelligent than someone with a better memory. “Specifically, we argue that transience enhances flexibility by reducing the influence of outdated information on memory-guided decision-making,” the professors continued. “And [this] prevents overfitting to specific past events – thereby promoting generalization.”
That news may come as something of a surprise to those who are prone to forgetfulness. In part, this could be down to just how frustrating a mental lapse can be – such as failing to remember why you walked into a room, for example. But even though experiencing a spell of forgetfulness may be exasperating, there may be a positive explanation behind it.
“According to this view, the goal of memory is not the transmission of information through time per se,” Richards and Frankland added at the start of the Neuron paper. “Rather, the goal of memory is to optimize decision-making. As such, transience is as important as persistence in mnemonic (memory) systems.”
Richards and Frankland had reached this conclusion after studying copious amounts of research into both human and animal brains. In addition, Frankland had embarked on his own experiment into memory by observing its effects on a group of mice.
In particular, Frankland had studied the hippocampus areas of the rodents’ respective brains, and by doing so he discovered that the animals’ older memories were being replaced by newer ones as time went on. This in turn matched up with his and Richards’ theory regarding the brain’s ability to drop needless knowledge.
Then, following the publication of his and Frankland’s paper in Neuron, Richards elaborated on its findings in an interview with CNN. And on that occasion, the scientist reiterated the fact that forgetfulness isn’t a bad thing by itself.
“It’s important that the brain forgets irrelevant details and instead focuses on the stuff that’s going to help make decisions in the real world,” Richards said. “If you’re trying to navigate the world and your brain is constantly bringing up conflicting memories, that makes it harder for you to make an informed decision.”
And in a 2017 article for British newspaper The Independent, Richards is quoted as going into a bit more detail on this last point. In particular, he explained why we sometimes remember certain things and experiences but fail to recall others.
“One of the things that distinguishes an environment where you’re going to want to remember stuff versus an environment where you want to forget stuff is this question of how consistent the environment is [as well as] how likely things are to come back into your life,” stressed Richards.
And in Richards’ opinion, some of the benefits that come with having a good memory – such as winning knowledge-based games – aren’t necessarily important from an evolutionary point of view. Indeed, the scientist revealed, being able to recall bits of trivia isn’t why our brains were originally shaped in the ways that they are today.
“We all admire the person who can smash Trivial Pursuit or win at Jeopardy,” Richards told CNN. “But the fact is that evolution shaped our memory not to win a trivia game but to make intelligent decisions. And when you look at what’s needed to make intelligent decisions, we would argue that it’s healthy to forget some things.”
Nevertheless, Richards wanted to make something clear on the subject of forgetfulness. You see, although both he and Frankland thought that not recalling every experience could be a broadly positive characteristic, the researcher opined that a very bad memory may actually be a sign of something more troubling.
“You don’t want to forget everything,” Richards continued. “And if you’re forgetting a lot more than normal, that might be cause for concern. But if you’re someone who forgets the occasional detail, that’s probably a sign that your memory system is perfectly healthy and doing exactly what it should be doing.”
Nor is it a prerequisite today to have an exceptional memory. Yes, given the plethora of technology available to us in the 21st century, there are many tools that can do the job of recalling certain pieces of information, as Richards went on to explain.
And Richards sees the benefits in having to resort to the internet or cell phones in order to check particular facts. “Instead of storing this irrelevant information that our phones can store for us, our brains are freed up to store the memories that actually do matter for us,” he said.
As for the best way to boost the health of your hippocampus? Well, according to Richards, regular exercise can help clear your brain of any unwanted information and thus free up space for new memories. And the scientist also had some words for those who may feel a bit reluctant to let go of the past.
“We know that exercise increases the number of neurons in the hippocampus,” Richards told CNN. “[That might lead you to forget your old memories], but they’re exactly those details from your life that don’t actually matter. And [these memories] may be keeping you from making good decisions.”