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Is my memory normal?
Is technology making my memory worse?
CHRISTOPHER ANDERSON/MAGNUM
I
Is my memory normal? Why do some people remember what they did years ago, whereas others have no clue, but never forget a face or are masters of the trivia quiz?
38 | NewScientist | 27 October 2018
I know that I went out for dinner last month, but I can’t remember anything about the experience How much we remember of events we have experienced seems to fall on a spectrum. At one extreme, some individuals are unable to form these kinds of memories at all. “People with severely deficient autobiographical memory syndrome would report an awareness of the fact they were at the dinner, but they don’t have a feeling of re-experiencing it. It’s more of a factual memory,” says neuropsychologist Brian Levine of the Rotman Research Institute in Toronto. At the opposite end of the spectrum are those with “higher superior autobiographical memories”, who can
S AN ostrich’s eye bigger than its brain? This kind of trivia question was once a cognitive workout, but when was the last time you really pondered a question, rather than simply turning to the internet for help? Then there are phone numbers and friends’ birthdays: information we once stored in our brain is now held in the smartphone in the palm of our hand. Outsourcing memories, for instance to pad and paper, is nothing new, but it has become easier than ever to do so using external devices, leading some to wonder whether our memories are suffering as a result. Probably the largest data dump is of snapshots of events, whether it is thousands of photos posted on social media or status updates documenting our lives. You might think that taking pictures and sharing stories helps you to preserve memories of events, but the opposite is true. When Diana Tamir at Princeton University and her colleagues sent people out on tours, those encouraged to take pictures actually had
recall in precise detail events from decades ago. The best-known case is that of a woman called Jill Price, who can recall most days of her life from the age of 11. The majority of us fall somewhere in between. Strong autobiographical memory skills are linked to the ability to form vivid visual memories of experiences, and probably to a strong sense of your own self-awareness.
Random memories pop spontaneously into my mind all the time Known as “mind pops”, these involuntary recalls happen to all of us, on average about 20 times a day, although there is a lot of variation between individuals. “It’s a basic
“Creating a hard copy of memories in media leaves a diminished copy in our own heads”
a poorer memory of the tour at a later date. “Creating a hard copy of an experience through media leaves only a diminished copy in our own heads,” she says. People who rely on a satellite navigation system to get around are also worse at working out where they have been than those who use maps. The mere expectation of information being at our fingertips seems to have an effect. When we think something can be accessed later, regardless of whether we will be tested on it, we have lower rates of recall of the information itself and enhanced recall instead for where to access it. “These kinds of studies suggest that technology is changing our memories,” says Sam Gilbert at University College London. “We increasingly don’t need to remember content, but instead, where to find it.” In some instances, this could be useful. When people were given two lists of words and asked to memorise them each in 20 seconds, those who were allowed to save the first list on a computer rather than deleting it before moving on to the next, could remember more information from the second list at a later date. It seemed as if cognitive offloading freed up vital brain resources that allowed them to better memorise new information. But relying too heavily on devices can mess with our appreciation of how good our memory actually is. We are constantly making judgements about whether something is worth storing in mind. Will I remember this
characteristic of autobiographical memory,” says Dorthe Berntsen of Aarhus University in Denmark, who studies this phenomenon. Once they pop into your head, they soon disappear. “They’re like dreams – if you don’t write them down, you forget all about them,” Berntsen says. We tend to experience more of these spontaneous memories as we age and retrieve fewer memories consciously, perhaps because we find it harder to inhibit thoughts as we get older. Berntsen’s work shows that they tend not to spring up when we are focused on a task, but are more likely to appear in dull moments. She thinks that, far from being an unwanted distraction, they are an important component of daily functioning.
tomorrow? Does it need to be written down? Should I set a reminder? This is called metamemory, and technology seems to screw it up. For instance, people who can access the internet to help them answer general knowledge questions, such as “How does a zip work?”, overestimate how much information they think they have remembered, as well as their knowledge of unrelated topics after the test, compared with people who answered the questions without going online. You lose touch with what came from you and what came from the machine. “These are subtle biases that may not matter too much if you continue to have access to external resources,” says Gilbert. “But if those resources disappear – in an exam, inan emergency, in a technological catastrophe – we may underestimate how much we would struggle without them. Having accurate insight into how good your memory actually is, is just as important as having a good memory in the first place.” For now, technology seems to be tweaking rather than upending our capacity for memory, but if the interface between us and devices merges more in the future, “the brain will really begin to adapt in ways we can’t anticipate right now”, says Martin Conway, director of the Centre for Memory and Law at City, University of London (see “Can I supercharge my memory?”, page 33). So if you are ever again asked about an ostrich brain, try the encyclopaedia in your head before reaching for your phone. Just remember, the answer is yes. Helen Thomson
These involuntary memories are often associated with the environment we are in, and there is a high probability they have relevance to the ongoing situation, she says. “They can give you an update, reminding you that last time you were in this situation you did this or that,” she says. But they are also cheap. “They don’t require the parts of the brain that require effort – executive functioning. If they are not relevant, you don’t have to think about them,” Berntsen says.
I can remember facts, but am rubbish at faces You might come across as rude if you don’t remember people, but don’t beat yourself up about it, everybody’s
memory is different. This could be down to innate differences in brain wiring. People with prosopagnosia, or face blindness, for example, can’t easily tell faces apart, even if they belong to people they know well. At the other end of the spectrum are super-recognisers, who have an amazing memory for faces. For the rest of us, our memory skills (or lack thereof) are more likely to be due to our life experiences and strategies we’ve picked up along the way. Most of us start out with roughly the same memory ability, but “subtle differences at the beginning get amplified by experiences and interests that build on each other. It’s not intrinsic, it’s acquired,” says neurologist Barry Gordon at Johns Hopkins University
FAQ. WHY DOES BEING STRESSED AFFECT YOUR MEMORY?
Emotion and memory go hand in hand. We secrete stress hormones, such as cortisol and adrenaline, when we are emotionally aroused, whether the result of a trauma or a fantastic concert. These hormones trigger the firing of signals in the brain, which promotes memory formation. The flip side is that when it comes to retrieving memories, stress can hamper our efforts. It can also prevent us from updating existing memories with new information. Which explains why, despite our best efforts, it is all too easy for the mind to go blank in the stressful setting of a presentation or the exam hall. YY
in Baltimore, Maryland. Expertise, prior knowledge and practice make a big difference to what we remember. Tests of chess masters, for example, show that they have a superior memory for patterns of pieces on a chessboard, but only for ones that are plausibly found in the game. Their ability to remember random positions is little better than that of novices. And studies on master memorisers who, for instance, can remember thousands of digits of the number pi, show that their superior powers of recall are due to strategies to “chunk” information into meaningful groups, not any innate talent for remembering. “They still need sticky notes on the fridge door to remember their shopping list,” says Gordon. Alison George 27 October 2018 | NewScientist | 39
CHRISTOPHER ANDERSON/MAGNUM
I
Is my memory normal? Why do some people remember what they did years ago, whereas others have no clue, but never forget a face or are masters of the trivia quiz?
38 | NewScientist | 27 October 2018
I know that I went out for dinner last month, but I can’t remember anything about the experience How much we remember of events we have experienced seems to fall on a spectrum. At one extreme, some individuals are unable to form these kinds of memories at all. “People with severely deficient autobiographical memory syndrome would report an awareness of the fact they were at the dinner, but they don’t have a feeling of re-experiencing it. It’s more of a factual memory,” says neuropsychologist Brian Levine of the Rotman Research Institute in Toronto. At the opposite end of the spectrum are those with “higher superior autobiographical memories”, who can
S AN ostrich’s eye bigger than its brain? This kind of trivia question was once a cognitive workout, but when was the last time you really pondered a question, rather than simply turning to the internet for help? Then there are phone numbers and friends’ birthdays: information we once stored in our brain is now held in the smartphone in the palm of our hand. Outsourcing memories, for instance to pad and paper, is nothing new, but it has become easier than ever to do so using external devices, leading some to wonder whether our memories are suffering as a result. Probably the largest data dump is of snapshots of events, whether it is thousands of photos posted on social media or status updates documenting our lives. You might think that taking pictures and sharing stories helps you to preserve memories of events, but the opposite is true. When Diana Tamir at Princeton University and her colleagues sent people out on tours, those encouraged to take pictures actually had
recall in precise detail events from decades ago. The best-known case is that of a woman called Jill Price, who can recall most days of her life from the age of 11. The majority of us fall somewhere in between. Strong autobiographical memory skills are linked to the ability to form vivid visual memories of experiences, and probably to a strong sense of your own self-awareness.
Random memories pop spontaneously into my mind all the time Known as “mind pops”, these involuntary recalls happen to all of us, on average about 20 times a day, although there is a lot of variation between individuals. “It’s a basic
“Creating a hard copy of memories in media leaves a diminished copy in our own heads”
a poorer memory of the tour at a later date. “Creating a hard copy of an experience through media leaves only a diminished copy in our own heads,” she says. People who rely on a satellite navigation system to get around are also worse at working out where they have been than those who use maps. The mere expectation of information being at our fingertips seems to have an effect. When we think something can be accessed later, regardless of whether we will be tested on it, we have lower rates of recall of the information itself and enhanced recall instead for where to access it. “These kinds of studies suggest that technology is changing our memories,” says Sam Gilbert at University College London. “We increasingly don’t need to remember content, but instead, where to find it.” In some instances, this could be useful. When people were given two lists of words and asked to memorise them each in 20 seconds, those who were allowed to save the first list on a computer rather than deleting it before moving on to the next, could remember more information from the second list at a later date. It seemed as if cognitive offloading freed up vital brain resources that allowed them to better memorise new information. But relying too heavily on devices can mess with our appreciation of how good our memory actually is. We are constantly making judgements about whether something is worth storing in mind. Will I remember this
characteristic of autobiographical memory,” says Dorthe Berntsen of Aarhus University in Denmark, who studies this phenomenon. Once they pop into your head, they soon disappear. “They’re like dreams – if you don’t write them down, you forget all about them,” Berntsen says. We tend to experience more of these spontaneous memories as we age and retrieve fewer memories consciously, perhaps because we find it harder to inhibit thoughts as we get older. Berntsen’s work shows that they tend not to spring up when we are focused on a task, but are more likely to appear in dull moments. She thinks that, far from being an unwanted distraction, they are an important component of daily functioning.
tomorrow? Does it need to be written down? Should I set a reminder? This is called metamemory, and technology seems to screw it up. For instance, people who can access the internet to help them answer general knowledge questions, such as “How does a zip work?”, overestimate how much information they think they have remembered, as well as their knowledge of unrelated topics after the test, compared with people who answered the questions without going online. You lose touch with what came from you and what came from the machine. “These are subtle biases that may not matter too much if you continue to have access to external resources,” says Gilbert. “But if those resources disappear – in an exam, inan emergency, in a technological catastrophe – we may underestimate how much we would struggle without them. Having accurate insight into how good your memory actually is, is just as important as having a good memory in the first place.” For now, technology seems to be tweaking rather than upending our capacity for memory, but if the interface between us and devices merges more in the future, “the brain will really begin to adapt in ways we can’t anticipate right now”, says Martin Conway, director of the Centre for Memory and Law at City, University of London (see “Can I supercharge my memory?”, page 33). So if you are ever again asked about an ostrich brain, try the encyclopaedia in your head before reaching for your phone. Just remember, the answer is yes. Helen Thomson
These involuntary memories are often associated with the environment we are in, and there is a high probability they have relevance to the ongoing situation, she says. “They can give you an update, reminding you that last time you were in this situation you did this or that,” she says. But they are also cheap. “They don’t require the parts of the brain that require effort – executive functioning. If they are not relevant, you don’t have to think about them,” Berntsen says.
I can remember facts, but am rubbish at faces You might come across as rude if you don’t remember people, but don’t beat yourself up about it, everybody’s
memory is different. This could be down to innate differences in brain wiring. People with prosopagnosia, or face blindness, for example, can’t easily tell faces apart, even if they belong to people they know well. At the other end of the spectrum are super-recognisers, who have an amazing memory for faces. For the rest of us, our memory skills (or lack thereof) are more likely to be due to our life experiences and strategies we’ve picked up along the way. Most of us start out with roughly the same memory ability, but “subtle differences at the beginning get amplified by experiences and interests that build on each other. It’s not intrinsic, it’s acquired,” says neurologist Barry Gordon at Johns Hopkins University
FAQ. WHY DOES BEING STRESSED AFFECT YOUR MEMORY?
Emotion and memory go hand in hand. We secrete stress hormones, such as cortisol and adrenaline, when we are emotionally aroused, whether the result of a trauma or a fantastic concert. These hormones trigger the firing of signals in the brain, which promotes memory formation. The flip side is that when it comes to retrieving memories, stress can hamper our efforts. It can also prevent us from updating existing memories with new information. Which explains why, despite our best efforts, it is all too easy for the mind to go blank in the stressful setting of a presentation or the exam hall. YY
in Baltimore, Maryland. Expertise, prior knowledge and practice make a big difference to what we remember. Tests of chess masters, for example, show that they have a superior memory for patterns of pieces on a chessboard, but only for ones that are plausibly found in the game. Their ability to remember random positions is little better than that of novices. And studies on master memorisers who, for instance, can remember thousands of digits of the number pi, show that their superior powers of recall are due to strategies to “chunk” information into meaningful groups, not any innate talent for remembering. “They still need sticky notes on the fridge door to remember their shopping list,” says Gordon. Alison George 27 October 2018 | NewScientist | 39