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"Jaroslav Flegr is no kook. And yet, for years, he suspected his mind had been taken over by parasites that had invaded his brain. So the prolific biologist took his science-fiction hunch into the lab. What he’s now discovering will startle you. Could tiny organisms carried by house cats be creeping into our brains, causing everything from car wrecks to schizophrenia? A biologist’s science- fiction hunch is gaining credence and shaping the emerging science of mind- controlling parasites."
"A new study of the brain by University of Cambridge scientists explains why some people can’t tell the difference between what they saw and what they imagined or were told about — such as whether they or another person said something, or whether an event was imagined or actually occurred."
Explanations of psychological phenomena seem to generate more public interest when they contain neuroscientific information. Even irrelevant neuroscience information in an explanation of a psychological phenomenon may interfere with people's abilities to critically consider the underlying logic of this explanation.
"Unrealistic optimism is a pervasive human trait that influences domains ranging from personal relationships to politics and finance. How people maintain unrealistic optimism, despite frequently encountering information that challenges those biased beliefs, is unknown. We examined this question and found a marked asymmetry in belief updating. Participants updated their beliefs more in response to information that was better than expected than to information that was worse. This selectivity was mediated by a relative failure to code for errors that should reduce optimism. "
"Basically, human optimism is a neurological bug that prevents us from remembering undesirable information about our odds of dying or being hurt. And that's why nobody ever believes the apocalypse is going to happen to them."
"In recent years popular science writing has bombarded us with titillating reports of discoveries of the brain’s psychological prowess. Such reports invade even introductory patter in biology and psychology. We are told that the brain — or some area of it sees, decides, reasons, knows, emotes, is altruistic/egotistical, or wants to make love. For example, a recent article reports a researcher’s “looking at love, quite literally, with the aid of an MRI machine.” One wonders whether lovemaking is to occur between two brains, or between a brain and a human being.
There are three things wrong with this talk."
Welcome to the The Law and Neuroscience Blog--which we have created to provide an on-line forum where the members of the MacArthur Law and Neuroscience Project (LANP) can share their ideas and interact with not only other researchers but also with the interested public more generally. One of the main goals of the blog is to provide people with a resource for finding out about cutting edge research at the cross-roads of neuroscience, law, and philosophy.
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These are purely physical systems, but the brain has much in common with them. Networks of brain cells alternate between periods of calm and periods of instability - "avalanches" of electrical activity that cascade through the neurons. Like real avalanches, exactly how these cascades occur and the resulting state of the brain are unpredictable.
It might seem precarious to have a brain that plunges randomly into periods of instability, but the disorder is actually essential to the brain's ability to transmit information and solve problems. "Lying at the critical point allows the brain to rapidly adapt to new circumstances," says Andreas Meyer-Lindenberg from the Central Institute of Mental Health in Mannheim, Germany.
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The neuronal avalanches that Beggs investigated, for example, are perfect for transmitting information across the brain. If the brain was in a more stable state, these avalanches would die out before the message had been transmitted. If it was chaotic, each avalanche could swamp the brain.
At the critical point, however, you get maximum transmission with minimum risk of descending into chaos. "One of the advantages of self-organised criticality is that the avalanches can propagate over many links," says Beggs. "You can have very long chains that won't blow up on you."
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Self-organized criticality is an attractive model for human brain dynamics, but there has been little direct evidence for its existence in large-scale systems measured by neuroimaging. In general, critical systems are associated with fractal or power law scaling, long-range correlations in space and time, and rapid reconfiguration in response to external inputs. Here, we consider two measures of phase synchronization: the phase-lock interval, or duration of coupling between a pair of (neurophysiological) processes, and the lability of global synchronization of a (brain functional) network. Using computational simulations of two mechanistically distinct systems displaying complex dynamics, the Ising model and the Kuramoto model, we show that both synchronization metrics have power law probability distributions specifically when these systems are in a critical state. We then demonstrate power law scaling of both pairwise and global synchronization metrics in functional MRI and magnetoencephalographic data recorded from normal volunteers under resting conditions. These results strongly suggest that human brain functional systems exist in an endogenous state of dynamical criticality, characterized by a greater than random probability of both prolonged periods of phase-locking and occurrence of large rapid changes in the state of global synchronization, analogous to the neuronal “avalanches” previously described in cellular systems. Moreover, evidence for critical dynamics was identified consistently in neurophysiological systems operating at frequency intervals ranging from 0.05–0.11 to 62.5–125 Hz, confirming that criticality is a property of human brain functional network organization at all frequency intervals in the brain's physiological bandwidth.
As our understanding of the brain has improved, however, it has become clear that a more accurate model depends on how these modules are wired together in circuits. A technique called diffusion tensor imaging (DTI) gives us a tool to probe the nature of those connections. A recent study suggests, for instance, that the more a person seeks out new experiences and relies on social approval, the stronger his or her wiring is among brain areas involved in reward, emotion and decision making.
This study shows that the reorganizational changes which occur following amputation are reversible. 35 years after Savage lost his hand, the organization of his somatosensory cortex returned to a state that is indistinguishable from what would have been expected in before the amputation, even though the functional reorganization would have increased with time.
I don't reject the idea that the brain is necessary for consciousness; but I do reject the argument that it is sufficient. That's just a fancy, contemporary version of the old philosophical idea that our true selves are interior, cut off from the outside world, only accidentally situated in the world. The view I'm attacking claims that neural activity is enough to explain consciousness, that you could have consciousness in a petri dish. It supposes that consciousness happens inside the brain the way digestion occurs inside the GI tract. But consciousness is not like digestion; it doesn't happen inside of us. It is something we do, something we achieve. It's more like dance than it is like digestion.
in list: Philosophy Notes
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Imagine that we find the Holy Grail of neurobiology, the patterns of neural activation that correlate perfectly with different events in our mental lives. We would still never understand or make sense of why those correlations exist. There is no intrinsic relationship between the experience and the neural substrates of the experience. We always need to look at what factors bring the two together. The environment, other people, our needs and desires -- all these things exist outside the brain and have to be seen as essential parts of our selves and consciousness. So we aren't just our brains, we're not locked inside our craniums; we extend beyond our skulls, beyond our skin, into the world we occupy.
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Boyer would say that much of the reason I was so affected by the Elijah ritual is that the concept of a spirit who slips through walls and drinks from a glass with invisible lips violated my intuitive understanding of what a human being is and what a human being does. These counterintuitive aspects of Elijah, then, get us latter-born Jews to really perk up our ears when our parents tell us about this mysterious character.
Boyer sometimes uses the term ‘sticky’ to describe religious concepts. They’re especially hard to shake, he says, because they’re continually grabbing our attention by virtue of the fact that they challenge our innate understanding of the humdrum world. In Elijah’s case, it’s being a person and therefore having a mind that works like any person’s mind. That is to say, you didn’t have to be told that Elijah has a mind basically like ours; you just inferred that he’s got human thoughts, interests, and desires rather than, say, those of a red squirrel. Yet, then again, he’s not exactly like us after all because he’s also an invisible person. And that grabs our attention and makes him especially memorable. -
First, in order for a concept to function properly as a religious concept, and thus to migrate successfully between minds, it must be “minimally” counterintuitive. That is to say, it can’t be so effortful that we can’t wrap our heads around it, such as an invisible tree that changes colors sometimes on Wednesdays, always Fridays and never Tuesdays, except every other week. These concepts are so cognitively taxing that they flicker out while we’re still scratching our heads over them, failing to ever register in the community mindset. For real staying power, a religious concept has to be comprehensible at the very least. It’s not that a thirsty chunk of ivory makes particularly good sense or is logical, but we can easily understand what a religious devotee means when they tell us about one.
Another caveat to Boyer’s formula is that not all minimally counterintuitive concepts are religious or supernatural. Rather, most such concepts, such as the idea of a skateboarding rodent named Stuart who dresses in cardigan sweaters, or a high school senior with spinnerets embedded in his wrists for expelling spider web silk, are clearly in the realm of fantasy. Unlike gods and spirits, these things are not generally believed by people to really and truly exist.
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