Are memories just pasta?

I just read a really fun description of memories in a Nautilus post: The pasta theory of memory & your personal beginning of time. It’s a post on childhood amnesia, the frustrating phenomenon that we just don’t remember much from the earliest part of our lives.

The piece is written by Dana Mackenzie, but the rich title inspiration comes from an Emory University psychologist that he interviewed, Patricia Bauer. Here’s how Bauer describes children’s memory:

“I compare memory to a colander,” Bauer says. “If you’re cooking fettucine, the pasta stays in. But if you’re cooking orzo, it goes right through the holes. The immature brain is a lot like a colander with big holes, and the little memories are like the orzo. As you get older, you’re either getting bigger pasta or a net with smaller holes.”

Image: http://www.onceuponachef.com/2011/12/fettuccine-bolognese.html
Image: http://www.onceuponachef.com/2011/12/fettuccine-bolognese.html

Why do I like this metaphor? It paints a nice picture of what happens. Kids still make memories, but those memories tend to escape. Older people’s memories are more likely to be contained by the colander brain.

This metaphor is compelling, but is it the best thing since sliced bread? Pasta easily trumps bread on my carbs hierarchy, but what about in the context of describing memory? Importantly, it demonstrates that children retain fewer memories than adults (which we probably don’t need much convincing of), but it doesn’t tell us why this is so. Why are children’s memories orzo-like, and how to do they become fettucine-like over time? There’s a lot about this process that scientists still don’t know, but the metaphor can’t capture those things they actually do know. For example, Mackenzie acknowledges in the piece, when we retell a memory, we increase our chances of remembering that event later (though retelling memories also introduces inaccuracies that seem to increase the more we retell…). A similar issue with the metaphor is that our brains are constantly changing, and a large part of the reason that kids don’t remember as much as adults do results from that dynamic property. But colanders don’t change as they age, so the pasta metaphor might make it less evident that the massive changes that take place in our brains underlie many of the memory differences throughout our lives.

Metaphors highlight some things – they play up certain features of the two things they’re comparing, and they downplay others. It’s probably not possible to accurately capture every important aspect of a phenomenon like childhood amnesia in one metaphor. And that’s ok, because metaphors can be supplemented by other information. But metaphors don’t only leave out relevant details. They can also mislead, as I think the static colander has the potential to do. Maybe the best way, then, to communicate the complexity of childhood amnesia is to remind ourselves (and those we’re communicating with) that although some features of children’s forgetting and orzo pasta do map onto each other well, other features, like the colander, fall short – at least until we design one that develops in a brain-like way over the course of its lifespan.

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Brain + Body + World = Mind

Where does cognition come from? The most common claim is probably that cognition resides in the brain. But that can’t be enough. The idea of a bodiless brain is pretty disturbing – could a brain in a jar produce true cognition? The externalist (embodiment) philosophy maintains that the interaction among brain, body, and world is crucial;  these three components together give rise to the mind, and no one is sufficient on its own.

brain
Image: http://science.dodlive.mil/2013/07/17/brain-emulation-behavior-modeling-ai-in-healthcare/

 

The brain is the most obvious contributor to cognition. Neuroscience research is based in the idea that a better understanding of the brain will bring about a better understanding of thinking and behavior. Fuster demonstrates his belief in the primacy of the brain by claiming “our memories are networks of interconnected cortical neurons, formed by association, that contain our experiences in their connectional structure” (451). His use of the verb “to be” instead of phrases like “are created by” or “result from” exemplifies his commitment to the preeminence of the brain. Fuster explains complex cognitive phenomena in terms of their underlying brain events. For example, he describes working memory as a temporary activation of a network of perceptual and motor memories, or, more simply, as the product of neural events.

Image: http://science.dodlive.mil/2013/07/17/brain-emulation-behavior-modeling-ai-in-healthcare/
Image: http://science.dodlive.mil/2013/07/17/brain-emulation-behavior-modeling-ai-in-healthcare/

A number of researchers opposed to this brain-centered view advocate for the importance of the body in cognition. After all, every brain is situated in a body. Ballard emphasizes the vitality of the body. Specifically, he points out the central role that they eyes can play in a number of tasks requiring working memory. In one experiment, he showed participants a structure made of a number of different blocks. They had a resource area containing the same blocks they would need to duplicate the model, and were asked to do so in a separate workspace area. As they moved blocks from the resource area to the workspace area, participants looked back at the model much more than they should have if they had stored a representation of the model in working memory. In fact, the most common strategy was to look from the model, to the pick-up area, back to the model, and then to the drop area for each block. Thus, Ballard concludes, subjects used fixation as a deictic pointing device presumably because the computational costs of storing the model in memory (a cognitive task) were greater than the on-line costs of shifting their eyes. In sum, the paper provided a unique example of the connectedness of the physical body and the brain’s processes.

Just as brains are situated in bodies, bodies are situated in the world, so it is unsurprising that the world is likewise crucial for cognition. Spivey uses eye-movement experiments to demonstrate the role of the external visual environment in numerous types of cognition. In one especially persuasive experiment, participants listened to descriptions of spatiotemporally dynamic scenes while facing a large white screen. For example, they might hear a description of events unfolding in a skyscraper. Narration might start talking about an occurrence on a lower floor and continue describing events higher up sequentially. Even though subjects were looking at a blank screen, their eye movements corresponded with the direction of the description (in the case of the example, their eyes would shift upward with the description). Spivey argues that the physical eye movements are an integral part of language processing, and more broadly that physical movements enable many types of cognition.

Kirsh also presents numerous real-world examples of people’s use of their physical environments. Drawing from instances of people cooking, packing groceries at the supermarket, personal workshops and playrooms, and playing Tetris, he shows that the spatial arrangements we create in our own environments help simplify choices, perception, and computation. We simplify choices, for example, when we lay vegetables that need to be washed next to the sink because the proximity of the items makes the desired action (washing) more salient and undesired actions (like chopping) less salient. One way we simplify perception is by symbolically marking an object. He gives the example of a  woman who, after measuring an amount of butter and cutting the stick in two, laid her knife on the measured piece to act as a sort of reminder. Finally, a Tetris game demonstrates our ability to use our environment to simplify computation. Approximately 800 to 1800ms after a zoid enters the screen, people display a burst of rotations, presumably because actually rotating the zoid takes less time than mentally rotating it. Thus, he concludes, humans use a variety of strategies to optimize their environments for cognition in many tasks.

Image: http://www.edge-online.com/news/tetris-relieves-post-traumatic-stress/
Image: http://www.edge-online.com/news/tetris-relieves-post-traumatic-stress/

Mind can emerge only when brain, body, and world come together. In this sense, “mind is best measured by its capabilities, not by its capacities” (Spivey, p. 183). Although the brain is undeniably an important contributor to thought and behavior, the physical presence of neurons and their connections does not alone constitute cognition. The bodies in which brains are found and the worlds in which the bodies are found are also crucial components of the human mind and cognition. Evidence from a variety of contexts has shown the importance of embodiment, or as Spivey concisely noted, “it might just be that your mind is bigger than your brain” (p. 162).

The persuasiveness of a pretty brain

I’m willing to guess when asked what the most attractive part of the human body is, not too many people respond that it’s the brain. But humans have demonstrated time and time again that our introspection into our thought processes is not nearly as accurate as we think, and it turns out that we judge scientific articles as sounder when there’s an image, or even the mention, of a brain.

This study by McCabe & Castel revealed that  people (undergrads in psych classes, to be more precise) who were given an article that included an image of a brain judged it as sounder than those who received the same article with either a graph or with no visual.

The less-convincing graph given to some participants next to the more-convincing brain images given to others.
The less-convincing graph given to some participants next to the more-convincing brain images given to others.

In order to examine whether the articles with the brain images seemed sounder because the images were visually complex, they reproduced the study, giving students either the same brain images or equivalent topological maps (more complex), and found that again, the brain-image-laden articles were rated as sounder.

The more visually complex, but less convincing topological map next to the more persuasive brain image
The more visually complex, but less convincing, topological map next to the more persuasive brain image

In a final experiment, they gave participants the same existing BBC article, either with or without a brain image, and participants who received the image rated the article’s conclusion more highly than those who did not. The images never added any information to the articles in which they were presented, but that fact was irrelevant to students’ judgments. As gimmicky as it might sound, this is worth noting if you want to publish a scientific piece with a broad public impact.

In another study, Weisberg and colleagues gave all participants simple descriptions of psychological phenomena, some with an irrelevant neuroscientific explanation accompanying the general description, and others without. Overall people preferred the explanations accompanied by the neuroscience. The neuroscience seemed to especially enhance their satisfaction with the explanation when the explanation itself was bad. Luckily, this effect did not hold up with actual neuroscientists, who tended to rate explanations lower when they were accompanied by unnecessary neuroscience jargon. Pretty interesting that the inclusion of a few high-level lexical inclusions can significantly alter our perceptions of an explanation, even when those words only add extraneous information…

Bottom line: All of my posts on this blog will contain brain images from now on.

My new brain bucket

When I was little, I rode my bike all the time. In the safety of my own, seemingly-large, U-shaped driveway, and in the quiet cul-de-sac by my house. My elementary school was on a long dead-end street with only two houses, and when I wanted to really live dangerously, I’d speed down its big hills (and then walk my bike up them). This was my prior experience with biking, but upon moving to a bike-friendly city in which I am carless, I got a new bike, strapped on my helmet, and with a mix of confidence and fear, took to the road. This haiku (from The Little Book of Neuroscience Haikus, my new favorite book) is in honor of my new wheels:

Helmet for my head

Protecting critical mass

Useful brain bucket.

(The book also notes that wearing a brain bucket can reduce the risk of head injury up to 85%, just FYI)

Do we really think of brains like we talk about them?

I just read an interesting post by Christian Jarrett called “‘My Brain Did It!’ Neuro Talk in Everyday Conversation.” He comments on how with the increase of scientific information regarding our brains, people use more and more language that suggests their brain is an autonomous, computer-like agent, separate from their bodies (things like “this menu confuses my brain” or “I can feel my brain whirring”). Perhaps, one researcher has suggested, language like this reflects people’s materialistic beliefs that the mind is reducible to the brain. In other words, they think that their thoughts, feelings, and emotions are equivalent to the physiological processes occurring in their brains. There’s also the possibility that an increase of language that suggests that mind=brain will influence people’s beliefs about their minds and their selves.

Image: rachelolsen.com
Image: rachelolsen.com

This is interesting, but I’m not convinced (about either). The possibility was also mentioned that we talk about our thoughts and feelings by referencing the brain for pragmatic reasons- it can facilitate getting our point across in certain circumstances. This seems more likely to me, first because I think most people actually hold a dualist view of the mind, one that contrasts pretty starkly with the mind=brain viewpoint. People who believe in an afterlife or those who believe in paranormal activity have to believe that there is more to our minds, or our souls, than just the physical brain.

Another reason that I don’t think language about the brain reflects speakers’ beliefs about their minds is that we talk about other body parts in similar ways, but we certainly don’t believe that they operate in isolation. We often say that our heart is breaking or that our stomach wants food, but we know that these organs don’t actually break or have desires.

It does seem like there could be some cool research opportunities here. Do some people use materialist-sounding language more often than others? And does their language use correlate with their beliefs about the mind? Actually, does the average person (who might say something like “my brain said, ‘you can do it,’ but my body said, ‘no, you can’t’) even have beliefs about whether his mind is reducible to the brain?

Brain Porn

This article by Sally Satel really hit the nail on the head for me by articulating some fMRI feelings I’ve had more eloquently than I could do myself. Brain scans are undoubtedly pretty:

fMRI
Image: http://psychcentral.com/lib/2007/what-is-functional-magnetic-resonance-imaging-fmri/

And the idea that we might be able to understand what’s going on when we have certain thoughts and emotions and even to induce them is really seductive.

But it leaves out context, the most crucial ingredient in understanding the mind. fMRI scans are necessarily done in a lab, specifically in a really noisy, claustrophobic machine. Personally, most of the thoughts and feelings I have in life don’t occur in that environment. They occur in real-life situations, with other people, and in situations in which I’m not aware that I’m being scrutinized. Without a doubt, fMRI data teach us a lot about the human brain and some correlates of thoughts and emotions, but it’s not the single explanation for all that goes on in our minds, as many people wish and expect it to be. Satel writes that “mechanism is not meaning. The brain creates the mind through the actions of neurons and circuits, yes, but it cannot reveal its nuanced contents.”

If we want to truly understand the thoughts and feelings that make us human, we have to look beyond the pervasive pretty rainbow pictures of “brain porn” that may at first seem enticing, but in the long run won’t bring the satisfaction we’re looking for.

Brain Wars Review

I just finished Brain Wars: The Scientific Battle Over the Existence of the Mind and the Proof That Will Change the Way We Live Our Lives.

materialism

Put concisely, I loved it. Mario Beauregard challenges the dominant materialistic view among scientists that mind = brain. He presents a number of phenomena that can’t be explained by materialism, such as placebos, neurofeedback, meditation, psi, hypnosis, and out of body/near death experiences. All of these are examples of ways that thoughts, beliefs, and emotions can influence what happens in our brains and bodies and affect our heath and well-being. In other words, our physical bodies don’t seem to be wholly determined by our physical brains.

“Mental activity is not the same as brain activity, and we are not “meat puppets,” totally controlled by our brains, our genes, and our environments. Indeed, our minds and our consciousness can significantly affect events occurring in the brain and body, and outside the body. We do have these immensely important capacities, and it is time for science to begin taking them seriously.”

For a while I’ve felt torn regarding the mind-brain relationship. If scientists didn’t believe that studying the brain would inform them about the mind and consciousness, why would they study it? But at the same time, people are drawn towards the idea that there is more to the mind than simply the physical brain, or else they would not practice religions geared towards life after death, when the mind transcends the physical. It’s always felt like a bit of an impasse.

Beauregard’s claim is that the mind and the physical world aren’t actually separated, but instead they just appear to be. They are distinct but complementary aspects of one reality.

brain-mind

In the conclusion, he talks about what the brain sciences can learn from Quantum Mechanics:

“The work of QM has effectively dematerialized the classical universe by showing that it is not made of minuscule billiard balls, as drawing of atoms and molecules would lead us to believe. QM has shown that atoms and subatomic particles are not really objects- they do not exist with certainty at definite spatial locations and definite times. Rather they show ‘tendencies to exist,’ forming a world of potentialities within the quantum domain.”

In the future, he argues, we won’t make progress in understanding the relationship between the brain and mind until scientists can shed their insistence on materialism, which causes them to “neglect the subjective dimension of human experience and downplay the importance of mind and consciousness.” When we have firm expectations about what we’ll find when approaching a research problem, it comes as no surprise that those expectations are met. If we want to understand the human mind as fully as possible, on the other hand, we have to be more open to different possibilities.