Finding the right search parameters

I was making dinner last week, and the recipe called for soy sauce.  I knew we had a bottle of it -- and I was pretty sure it was somewhere in the door shelves of the fridge, amongst the various salad dressings, jellies, jams, sauces, and marinades we'd collected.  But I could not find the damn thing, and was becoming increasingly frustrated.

So instead of a quick scan -- usually sufficient to find what I'm looking for -- I decided on a one-at-a-time, bottle-by-bottle search, and as you've probably already guessed, I found the soy sauce in under thirty seconds.  I realized immediately what the problem was; in my mind I pictured it as having a red cap, and our bottle had a green cap.

You'd think that wouldn't make a difference, given that everything else about it was exactly like what I was picturing, up to and including being full of soy sauce and having a big label on the front that said, "SOY SAUCE."  But one piece of the search parameter was off, and that made me scan right past it, not once but several times.

[Image licensed under the Creative Commons GanMed64, Soy Sauce selection (6362318717), CC BY 2.0]

This is far from the first time this sort of thing has happened to me, and it amazes me how subtle the error can be and still derail my efforts.  It doesn't have to be anything nearly as egregious as in the hilarious anecdote Dave Barry writes about when his mother, groceries in a cart and two small children in tow, spent an hour trying to find her car in the store parking lot.  She looked so pathetic that several kind shoppers pitched in to try to help her.  "It's a black Chevrolet," she said, over and over.  It was only after the search had gone on for a ridiculous length of time, up and down the parking lot lanes, that she remembered that the previous week they'd traded in their old car for a new one, and told the helpers, "Wait!  I just realized, it's not a black Chevrolet, it's a yellow Ford!"

The helpers apparently were not amused, and his mom spent the rest of her life trying to live down the embarrassment.

So we can be confounded by our brain's preconceived notions of what we're looking for, from the subtle to the (should be) obvious.  And some researchers at Johns Hopkins University have found that finding the right search parameters even extends to characteristics we can't see.

This puzzling result came out of a series of experiments that were the subject of a paper this week in the Journal of Experimental Psychology.  The team, led by cognitive neuroscientist Li Guo, timed how long it took test subjects to isolate a target object from clutter, and they found that knowing characteristics of the object that aren't apparent to the eye -- like hardness or fragility -- significantly improved the speed with which subjects could find the object in question.  The authors write:

Our interactions with the world are guided by our understanding of objects’ physical properties.  When packing groceries, we place fragile items on top of more durable ones and position sharp corners so they will not puncture the bags.  However, physical properties are not always readily observable, and we often must rely on our knowledge of attributes such as weight, hardness, and slipperiness to guide our actions on familiar objects.  Here, we asked whether our knowledge of physical properties not only shapes our actions but also guides our attention to the visual world.  In a series of four visual search experiments, participants viewed arrays of everyday objects and were tasked with locating a specified object.  The target was sometimes differentiated from the distractors based on its hardness, while a host of other visual and semantic attributes were controlled.  We found that observers implicitly used the hardness distinction to locate the target more quickly, even though none reported being aware that hardness was relevant.  This benefit arose from fixating fewer distractors overall and spending less time interrogating each distractor when the target was distinguished by hardness.  Progressively more stringent stimulus controls showed that surface properties and curvature cues to hardness were not necessary for the benefit.  Our findings show that observers implicitly recruit their knowledge of objects’ physical properties to guide how they attend to and engage with visual scenes.

What I find most curious about the results of this experiment is if the characteristic you're given can't be seen, how does it help your brain to locate the object you're searching for?  "What makes the finding particularly striking from a vision science standpoint is that simply knowing the latent physical properties of objects is enough to help guide your attention to them," said study senior author Jason Fischer.  "It's surprising because nearly all prior research in this area has focused on a host of visual properties that can facilitate search, but we find that what you know about objects can be as important as what you actually see...  To me what this says is that in the back of our minds, we are always evaluating the physical content of a scene to decide what to do next.  Our mental intuitive physics engines are constantly at work to guide not only how we interact with things in our environment, but how we distribute our attention among them as well."

So it may be that we're approaching our search from a set theory perspective; searching through "the set of all things in my living room" is more efficient if I can eliminate "the subset of things in my living room that are rigid, heavy, stand upright," etc., so eventually my brain can whittle it down to "the couch throw-pillow my dog dragged behind the recliner."

It's still puzzling to me how our brains actually accomplish this, because it means some kind of interaction is occurring between our visual interpretive systems and our non-visual memories (of such things as texture, durability, and so on).  It'd be interesting to have people perform this task while in a fMRI machine -- and see how their brain firing pattern differs while performing this task as compared to performing a task that simply requires memory retrieval.

So that's our latest look at the fascinating world of cognitive neuroscience.  It doesn't explain, however, the weird phenomenon that happens to me while I'm doing home repair projects, wherein I spend 5% of the time doing actual home repair and 95% stomping around swearing and looking for the tool that was just in my damn hand five seconds ago.  That one's a mystery.

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This week's Skeptophilia book-of-the-week is one that should be a must-read for everyone -- not only for the New Yorkers suggested by the title.  Unusual, though, in that this one isn't our usual non-fiction selection.  New York 2140, by Kim Stanley Robinson, is novel that takes a chilling look at what New York City might look like 120 years from now if climate change is left unchecked.

Its predictions are not alarmism.  Robinson made them using the latest climate models, which (if anything) have proven to be conservative.  She then fits into that setting -- a city where the streets are Venice-like canals, where the subways are underground rivers, where low-lying areas have disappeared completely under the rising tides of the Atlantic Ocean -- a society that is trying its best to cope.

New York 2140 isn't just a gripping read, it's a frighteningly clear-eyed vision of where we're heading.  Read it, and find out why The Guardian called it "a towering novel about a genuinely grave threat to civilisation."

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

The heart of the story

As a fiction writer, I am constantly working to make sure my writing is engaging.  What writers want, after all, is to keep readers turning the page, and when "The End" is reached, for them to go immediately to Amazon and order another.

I'm a "genre writer" -- paranormal/speculative fiction, with occasional forays into science fiction or horror -- and a lot of the writing in that realm is highly plot-driven.  Keep things moving, don't dawdle too much on setting and description, make every page exciting and every chapter ending a cliffhanger.  But some new research out of McMaster University has illustrated something I've always believed -- however plot-dense it is, all stories are, at their heart, character stories.

What the researchers did is hook people up to an fMRI machine, presented them with a brief prompt -- things like, "A fisherman rescues a boy from a freezing lake" -- and asked them to express the story behind the prompt in spoken word, written word, or drawings.

[Image is in the Public Domain]

The results are fascinating.  In each case, and no matter what the prompt, the test subjects' brains responded the same way.  The network called "theory-of-mind" -- which responds to other people's motivations, personalities, beliefs, motives, and actions -- was the primary area that fired during the activity.  In spite of the fact that these characters were entirely fictional, and had not even been considered prior to the assignment of the prompt, the brain responded to their stories as if they were real people.

"We tell stories in conversation each and every day," said Steven Brown, associate professor of psychology, neuroscience, and behavior at McMaster, who was lead author of the study.  "Very much like literary stories, we engage with the characters and are wired to make stories people-oriented...  Aristotle proposed 2,300 years ago that plot is the most important aspect of narrative, and that character is secondary.  Our brain results show that people approach narrative in a strongly character-centered and psychological manner, focused on the mental states of the protagonist of the story."

Which I find absolutely fascinating, and which squares with my experience both as a writer and as a reader.  There have been times I've read books -- won't mention any names, out of courtesy to my fellow authors -- in which I've found the concept intriguing, but I have either not cared about the main characters or else actively disliked them.  And no matter how fascinating the plot, if I don't give a damn about the characters, why would I care enough to read to the end of the book?

I try my hardest to keep this in mind when I'm writing, and especially apropos of the characters who aren't likable.  It's easy enough to form an emotional attachment to the Good Guys, but a pet peeve of mine is Bad Guys who are one-dimensional.  Much as I love The Lord of the Rings, why was Sauron so damned nasty?  Did he actually like living in a wretched wasteland, and palling around with Orcs and Trolls and Giant Spiders and the like?  Did he finish his morning cup of coffee, and immediately look around for someone to torture?

Bad Guys -- even, in the case of Really Bad Guys like Sauron -- have to have some sort of motivation other than just being evil 'cuz they're evil.  In my own books, I had a striking experience with writing a character who is truly awful; Jackson Royce in this summer's release, The Fifth Day.  He is not a nice man.  But along the way (no spoilers intended) you begin to find out why he acts the way he does, and by the end, he's pitiable.  Still not likable, but pitiable.  I had one reader tell me, "Man, you had me hating Jackson and feeling terribly sorry for him at the same time.  I didn't think that was possible."

To me, that says that at least on that level, the story succeeded.

So it's fascinating that neuroscience has given us a first approximation to why we respond this way.  Humans are social primates; we're wired to react to the people around us, to parse their actions as if we could see inside their minds.  In other words, to put ourselves in their place, think whether we would have done the same, and try to ascribe motives to what they've done.

This tendency is so powerful that it activates even in the case of fictional characters.  Which, perhaps, explains why humans have been storytellers as long as there's been an audience of listeners and a campfire to sit around.

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This week's Skeptophilia book recommendation is a fun one.  If you've never read anything by Mary Roach, you don't know what you're missing.  She investigates various human phenomena -- eating, space travel, sex, death, and war being a few of the ones she's tackled -- and writes about them with an analytical lens and a fantastically light sense of humor.  This week, my recommendation is Spook, in which she looks at the idea of an afterlife, trying to find out if there's anything to it from a scientific perspective.  It's an engaging, and at times laugh-out-loud funny, read.

[If you purchase the book from Amazon using the image/link below, part of the proceeds goes to supporting Skeptophilia!]

I'm sure I already told you about this...

One of the most peculiar sensations in the world is déjà vu.  I typically have the auditory version -- I am completely convinced that I have had this conversation before.  Others tend to have more visual déjà vu, having a certainty that they've been in a place where they know they've never been.

I'd heard a number of explanations of the phenomenon -- that it was memory being triggered subliminally by another sense, or that it came from the fact that our sensory processing and cognitive processing were running at different speeds, so the by the time everything was integrated it created a false memory of an experience that had already occurred.  Neither of those has ever sounded all that convincing to me.

[image courtesy of the Wikimedia Commons]

Nor, I must add, did all of the woo-woo explanations, such as the idea that déjà vu was precognition, or a visitation by a ghost, or the recollection of an experience from a previous life.

Now, cognitive neuroscientists Josephine Urquhart and Akira O'Connor of the University of St. Andrews (Scotland) have devised an experiment that gives us at least a window on what might be going on -- by creating a situation where déjà vu can be induced.

The setup is simple and elegant.  You give your test subjects a list of words to memorize, and include several that have to do with sleeping -- bed, blankets, dreams, pillow.  "Sleep" itself is not included.  After studying the list, you ask the subjects if there were any words on the list beginning with the letter "s" (there weren't).  Afterwards, you ask them if the word "sleep" was on the list.

They know it couldn't have been, because they all answered in the negative regarding there being words beginning with "s" -- but when asked the question, most of the test subjects experienced an eerie sense of déjà vu, that the word "sleep" actually was on the list -- or, perhaps, on another similar list they'd seen before, somewhere else.  Urquhart and O'Connor write:

Déjà vu is a nebulous memory experience defined by a clash between evaluations of familiarity and novelty for the same stimulus.  We sought to generate it in the laboratory by pairing a DRM recognition task, which generates erroneous familiarity for critical words, with a monitoring task by which participants realise that some of these erroneously familiar words are in fact novel...  The key omission in [prior] déjà vu generation procedures... is the provision of information allowing the participant to make an evaluation of unfamiliarity or novelty to clash with the experimentally-generated familiarity.  In these procedures, there was no objective standard by which participants could verify that the stimuli provoking familiarity had in fact not previously been encountered.

Interestingly, when the subjects were being tested, they were simultaneously being monitored by an fMRI scanner -- and when the feelings of déjà vu were the most intense, the areas in the brain involved in memory (such as the hippocampus) were not very active.  Instead, the frontal cortex -- the part of the cerebrum responsible for decision-making -- was lighting up like mad.

O'Connor and Urquhart believe that the explanation for this is that déjà vu comes from our memory's error-checking procedure.  When we are forming memories, the frontal cortex is doing a continual spot-check to make sure that what is being placed into memory is accurate.  When an error is noted, it's brought to our attention.  Most of the time, the error is something that can be resolved quickly -- with a conclusion of "okay, that's not the way it happened."  But when the memory being analyzed is close in content to something else, especially something that the conscious brain knows can't have occurred, it generates a conflict that is what results in the sensation of déjà vu.

This is still a tentative finding -- there is a great deal we don't understand about memory and sensory processing, so concluding that the phenomenon of déjà vu is explained is probably premature.  But to my thinking, this is a hell of a lot better explanation than anything else I've heard.  O'Connor and Urquhart are going to continue trying to explore the phenomenon.  As a mysterious sensation that is nearly universal to all humans, it certainly begs explaining.  But look for more studies coming down the pike.  And don't forget: you heard it here first.