It has become the most natural thing to do: get in the car, type a destination into a smartphone, and let an algorithm using GPS data show the way. Personal GPS-equipped devices entered the mass market in only the past 15 or so years, but hundreds of millions of people now rarely travel without them. These gadgets are extremely powerful, allowing people to know their location at all times, to explore unknown places and to avoid getting lost.
But they also affect perception and judgment. When people are told which way to turn, it relieves them of the need to create their own routes and remember them. They pay less attention to their surroundings. And neuroscientists can now see that brain behavior changes when people rely on turn-by-turn directions.
In a study published in Nature Communications in 2017, researchers asked subjects to navigate a virtual simulation of London’s Soho neighborhood and monitored their brain activity, specifically the hippocampus, which is integral to spatial navigation. Those who were guided by directions showed less activity in this part of the brain than participants who navigated without the device. “The hippocampus makes an internal map of the environment and this map becomes active only when you are engaged in navigating and not using GPS,” Amir-Homayoun Javadi, one of the study’s authors, told me. [Continue reading…]
Ditch the GPS. It’s ruining your brain
Feminists never bought the idea of the computational mind set free from its body. Cognitive science is finally catching up
We are shackled to the pangs and shocks of life, wrote Virginia Woolf in The Waves (1931), ‘as bodies to wild horses’. Or are we? Serge Faguet, a Russian-born tech entrepreneur and self-declared ‘extreme biohacker’, believes otherwise. He wants to tame the bucking steed of his own biochemistry via an elixir of drugs, implants, medical monitoring and behavioural ‘hacks’ that optimise his own biochemistry. In his personal quest to become one of the ‘immortal posthuman gods that cast off the limits of our biology, and spread across the Universe’, Faguet claims to have spent upwards of $250,000 so far – including hiring ‘fashion models to have sex with in order to save time on dating and focus on other priorities’.
It’s easy to roll our eyes at such outré displays of entitlement, seemingly endemic in the Silicon Valley set. Beyond Faguet, ‘transhumanist’ true believers awaiting their version of the rapture include the entrepreneur Elon Musk, the Googler Ray Kurzweil and the philosopher Nick Bostrom. Their transhumanist ideal resembles a late-capitalist rendering of Leonardo da Vinci’s Vitruvian man: an individual super-human, armed with a wealth of cognitive and physical enhancements, elevated to a state of unassailable strength and power, devoid of all dependency, and, often enough, endowed with the ability to reproduce without the inconvenience of women. As they describe it, ‘immortality’ sounds like nothing so much as manspreading into the future.
What’s most instructive about transhumanism, though, isn’t what it exposes about the hubris of rich white men. It’s the fact that it represents a paradigm case of what happens when a particular cast of mind, made from the sediment of centuries of philosophy, gets taken to its logical extreme. Since Plato, generations of philosophers have been gripped by a fear of the body and the desire to transcend it – a wish that works hand-in-hand with a fear of women, and a desire to control them. In the dialogue Timaeus, Plato likens the force of his ideal, immaterial forms to a disciplinarian father, imposing order on all this unwieldy material stuff that was nonetheless ‘the mother and receptacle of all created and visible and in any way sensible things’. Here Plato deploys a well-worn technique for suppressing corporeal angst: carving off the mind (rational, detached, inviolable, symbolically male) from the body (emotional, entangled, weak, symbolically female). [Continue reading…]
Seeing our expectations
Imagine picking up a glass of what you think is apple juice, only to take a sip and discover that it’s actually ginger ale. Even though you usually love the soda, this time it tastes terrible. That’s because context and internal states, including expectation, influence how all animals perceive and process sensory information, explained Alfredo Fontanini, a neurobiologist at Stony Brook University in New York. In this case, anticipating the wrong stimulus leads to a surprise, and a negative response.
But this influence isn’t limited to the quality of the perception. Among other effects, priming sensory systems to expect an input, good or bad, can also accelerate how quickly the animal then detects, identifies and reacts to it.
Years ago, Fontanini and his team found direct neural evidence of this speedup effect in the gustatory cortex, the part of the brain responsible for taste perception. Since then, they have been trying to pin down the structure of the cortical circuitry that made their results possible. Now they have. Last month, they published their findings in Nature Neuroscience: a model of a network with a specific kind of architecture that not only provides new insights into how expectation works, but also delves into broader questions about how scientists should think about perception more generally. Moreover, it falls in step with a theory of decision making that suggests the brain really does leap to conclusions, rather than building up to them. [Continue reading…]
Open to the unexpected: Why jazz musicians are more creative than classical musicians
Scientists at Wesleyan University have used electroencephalography to uncover differences in how the brains of Classical and Jazz musicians react to an unexpected chord progression.
Their new study, published in the journal Brain and Cognition, sheds new light on the nature of the creative process.
“I have been a classical musician for many years, and have always been inspired by the great jazz masters who can improvise beautiful performances on the spot,” explained study author Psyche Loui. “Whenever I tried to improvise I always felt inhibited and self-conscious, and this spurred my questions about jazz improvisation as a model for creativity more generally: What makes people creative improvisers, and what can this tell us about how we can all learn to be more creative?” [Continue reading…]
To improve memory, tune it like an orchestra
Anyone above a certain age who has drawn a blank on the name of a favorite uncle, a friend’s phone number or the location of a house key understands how fragile memory is. Its speed and accuracy begin to slip in one’s 20s and keep slipping. This is particularly true for working memory, the mental sketch pad that holds numbers, names and other facts temporarily in mind, allowing decisions to be made throughout the day.
On Monday, scientists reported that brief sessions of specialized brain stimulation could reverse this steady decline in working memory, at least temporarily. The stimulation targeted key regions in the brain and synchronized neural circuits in those areas, effectively tuning them to one another, as an orchestra conductor might tune the wind section to the strings.
The findings, reported in the journal Nature Neuroscience, provide the strongest support yet for a method called transcranial alternating current stimulation, or tACS, as a potential therapy for memory deficits, whether from age-related decline, brain injury or, perhaps, creeping dementia. [Continue reading…]
Can we get better at forgetting?
Whatever its other properties, memory is a reliable troublemaker, especially when navigating its stockpile of embarrassments and moral stumbles. Ten minutes into an important job interview and here come screenshots from a past disaster: the spilled latte, the painful attempt at humor. Two dates into a warming relationship and up come flashbacks of an earlier, abusive partner.
The bad timing is one thing. But why can’t those events be somehow submerged amid the brain’s many other dimming bad memories?
Emotions play a role. Scenes, sounds and sensations leave a deeper neural trace if they stir a strong emotional response; this helps you avoid those same experiences in the future. Memory is protective, holding on to red flags so they can be waved at you later, to guide your future behavior.
But forgetting is protective too. Most people find a way to bury, or at least reshape, the vast majority of their worst moments. Could that process be harnessed or somehow optimized?
Perhaps. In the past decade or so, brain scientists have begun to piece together how memory degrades and forgetting happens. A new study, published this month in the Journal of Neuroscience, suggests that some things can be intentionally relegated to oblivion, although the method for doing so is slightly counterintuitive.
For the longest time, forgetting was seen as a passive process of decay and the enemy of learning. But as it turns out, forgetting is a dynamic ability, crucial to memory retrieval, mental stability and maintaining one’s sense of identity.
That’s because remembering is a dynamic process. At a biochemical level, memories are not pulled from the shelf like stored videos but pieced together — reconstructed — by the brain. [Continue reading…]
How the brain links gestures, perception and meaning
The tendency to supplement communication with motion is universal, though the nuances of delivery vary slightly. In Papua New Guinea, for instance, people point with their noses and heads, while in Laos they sometimes use their lips. In Ghana, left-handed pointing can be taboo, while in Greece or Turkey forming a ring with your index finger and thumb to indicate everything is A-OK could get you in trouble.
Despite their variety, gestures can be loosely defined as movements used to reiterate or emphasize a message — whether that message is explicitly spoken or not. A gesture is a movement that “represents action,” but it can also convey abstract or metaphorical information. It is a tool we carry from a very young age, if not from birth; even children who are congenitally blind naturally gesture to some degree during speech. Everybody does it. And yet, few of us have stopped to give much thought to gesturing as a phenomenon — the neurobiology of it, its development, and its role in helping us understand others’ actions. As researchers delve further into our neural wiring, it’s becoming increasingly clear that gestures guide our perceptions just as perceptions guide our actions. [Continue reading…]
How the body and mind talk to one another to understand the world
By Sarah Garfinkel
Have you ever been startled by someone suddenly talking to you when you thought you were alone? Even when they apologise for surprising you, your heart goes on pounding in your chest. You are very aware of this sensation. But what kind of experience is it, and what can it tell us about relations between the heart and the brain?
When considering the senses, we tend to think of sight and sound, taste, touch and smell. However, these are classified as exteroceptive senses, that is, they tell us something about the outside world. In contrast, interoception is a sense that informs us about our internal bodily sensations, such as the pounding of our heart, the flutter of butterflies in our stomach or feelings of hunger.
The brain represents, integrates and prioritises interoceptive information from the internal body. These are communicated through a set of distinct neural and humoural (ie, blood-borne) pathways. This sensing of internal states of the body is part of the interplay between body and brain: it maintains homeostasis, the physiological stability necessary for survival; it provides key motivational drivers such as hunger and thirst; it explicitly represents bodily sensations, such as bladder distension. But that is not all, and herein lies the beauty of interoception, as our feelings, thoughts and perceptions are also influenced by the dynamic interaction between body and brain.
Evidence mounts that gut bacteria can influence mood, prevent depression
Of all the many ways the teeming ecosystem of microbes in a person’s gut and other tissues might affect health, its potential influences on the brain may be the most provocative. Now, a study of two large groups of Europeans has found several species of gut bacteria are missing in people with depression. The researchers can’t say whether the absence is a cause or an effect of the illness, but they showed that many gut bacteria could make substances that affect nerve cell function—and maybe mood.
“It’s the first real stab at tracking how” a microbe’s chemicals might affect mood in humans, says John Cryan, a neuroscientist at University College Cork in Ireland who has been one of the most vocal proponents of a microbiome-brain connection. The study “really pushes the field from where it’s been” with small studies of depressed people or animal experiments. Interventions based on the gut microbiome are now under investigation: The University of Basel in Switzerland, for example, is planning a trial of fecal transplants, which can restore or alter the gut microbiome, in depressed people.
Several studies in mice had indicated that gut microbes can affect behavior, and small studies of people suggested this microbial repertoire is altered in depression. To test the link in a larger group, Jeroen Raes, a microbiologist at the Catholic University of Leuven in Belgium, and his colleagues took a closer look at 1054 Belgians they had recruited to assess a “normal” microbiome. Some in the group—173 in total—had been diagnosed with depression or had done poorly on a quality of life survey, and the team compared their microbiomes with those other participants. Two kinds of microbes, Coprococcus and Dialister, were missing from the microbiomes of the depressed subjects, but not from those with a high quality of life. The finding held up when the researchers allowed for factors such as age, sex, or antidepressant use, all of which influence the microbiome, the team reports today in Nature Microbiology. They also found the depressed people had an increase in bacteria implicated in Crohn disease, suggesting inflammation may be at fault. [Continue reading…]
The cerebellum is your ‘little brain’ — and it does some pretty big things
For the longest time the cerebellum, a dense, fist-size formation located at the base of the brain, never got much respect from neuroscientists.
For about two centuries the scientific community believed the cerebellum (Latin for “little brain”), which contains approximately half of the brain’s neurons, was dedicated solely to the control of movement. In recent decades, however, the tide has started to turn, as researchers have revealed details of the structure’s role in cognition, emotional processing and social behavior.
The longstanding interest in the cerebellum can be seen in the work of French physiologist Marie Jean Pierre Flourens—(1794–1867). Flourens removed the cerebella of pigeons and found the birds became unbalanced, although they could still move. Based on these observations, he concluded the cerebellum was responsible for coordinating movements. “[This] set the dogma that the cerebellum was involved in motor coordination,” says Kamran Khodakhah, a neuroscientist at Albert Einstein College of Medicine, adding: “For many years, we ignored the signs that suggested it was involved in other things.”
One of the strongest pieces of evidence for the cerebellum’s broader repertoire emerged around two decades ago, when Jeremy Schmahmann, a neurologist at Massachusetts General Hospital, described cerebellar cognitive affective syndrome after discovering behavioral changes such as impairments in abstract reasoning and regulating emotion in individuals whose cerebella had been damaged. Since then this line of study has expanded. There has been human neuroimaging work showing the cerebellum is involved in cognitive processing and emotional control—and investigations in animals have revealed, among other things, that the structure is important for the normal development of social and cognitive capacities. Researchers have also linked altered cerebellar function to addiction, autism and schizophrenia.
Although many of these findings suggested the cerebellum played an important part both in reward-related and social behavior, a clear neural mechanism to explain this link was lacking. New research, published this week in Science, demonstrates that a pathway directly tying the cerebellum to the ventral tegmental area (VTA)—one of the brain’s key pleasure centers—can control these two processes. [Continue reading…]