Strolling Through The Park From Hell

Last night, over a seafood dinner at Halifax's Five Fisherman restaurant, Ken Hill described the trail system in nearby Hemlock Ravine Park (where I'm headed later today) as an "island maze" (i.e. this is a maze where no heuristic such as, keep making lefts, will get you out; research subjects he's taken out here can and do circle through the path system endlessly). I asked Hill who designed the paths originally. "I don't know," he said, "the Devil?"

A few years back, the park's overseers were getting so many complaints from people who got lost in the trails that they put up several "You Are Here" signs. According to Hill, these signs are "useless" and one is actually incorrect. We'll see. Hill says only one person he's ever tested out in this park (he walks them to a destination and asks them to lead him back to the starting point) has ever passed. "And that guy cheated," he explains. So, the pressure's off.

On another note, I forgot to post last week when I attended the Spatial Learning Conference at Harvard. It was focused on a theme I'm particularly interested in: individual differences. But, I attended only one of the days, because the majority of the presentations were about small-scale spatial ability (e.g. the ability to recognize a 3-d shape from different directions). It's an interesting bit of turbulence in the spatial cognition world between those who study large scale navigation and those who primarily focus on the small scale abilities. Researchers in both fields suggest some overlap in cognitive skills, but research by Mary Hegarty et al at UCSB showed that a self-rated sense-of-direction score (from a survey they developed) was a much better predictor of large-scale navigation than scores of small-scale spatial ability such as mental rotation. One exciting side note on this conference was learning, from one presenter, about a British autistic savant named Stephen Wiltshire who can draw amazingly detailed and proportionally accurate pictures of an unfamiliar city after a brief helicopter ride overhead.

Land of the Lost

I've booked my trip to Halifax (late May) to visit with Ken Hill, a psychologist at the St. Mary's University who researches lost-person behavior.

The quick story on Prof. Hill is that he started into this particular line of inquiry back in 1986 after volunteering in the search for a 9-year old boy who'd become lost in the Nova Scotia wilderness. After more than a week, they found the boy's body less than 3 kilometers from where he'd last been seen. So, Hill dedicated his research to making search-and-rescue more than just about covering as much ground as possible--coordinating search around probabilities based on behavior predictions that differ depending on who is lost--a 6 year old, a hunter, a bird watcher, an elderly person, etc.

Of course, there's a bit of Heisenberg uncertainty when trying to "study" lost person behavior.  Hill can only get so close to his subject, and one of his tactics is to get subjects lost in the maze-like path system of a local park in Halifax. He's promised to get me lost, there, too.

Quick note: Nova Scotia (specifically its swampy wilderness areas) was dubbed the "Lost Person Capital of North America" by Canadian Geographic Magazine.

A Picture Is Worth A Thousand Words, Except When It Isn't

Sorry. Long time, no blog. I had a phone conversation a few days ago with David Kraemer, a post-doctoral fellow at the University of Pennsylvania's Center for Cognitive Neuroscience. To oversimplify, Kraemer is investigating the idea of "learning styles" (you know, the popular idea in education circles that we are either visual or verbal learners and that instructional materials should be so-catered ).  There are other "learning styles" out there, too, but visual and verbal are two mainstays. But, it turns out there's not a great deal of scientific support for this, says Kraemer, at least not for the theory as it's popularly perceived (i.e. learning styles appear someplace on a visual-verbal continuum, and so the more visual you are the less verbal, etc).

Anyway, Kraemer's adding spatial learning to the visual mix, as differentiated from "object" visual learning (a 3-D vs. 2-D distinction). And, lucky for me, he's testing all of these learning styles as they affect (or don't) our ability to navigate. When I was in Philly, I explored a bunch of desktop virtual cities for him after I filled out a few questionnaires meant to determine if I was more of a verbal or visual or spatial learner, etc. The city explorations were all videos of routes. I floating through a dozen or so deserted intersections, sometimes turning and sometimes not. The testing broke down like this:

1. View pictures of solitary buildings and say whether or not they were part of the city you just explored.
2. View pictures of intersections and say whether you turned right or left, or went straight through, or if the intersection wasn't part of the city you just explored.
3. View a picture of an intersection and then a picture of another intersection elsewhere in the city. "Point" using designated keyboard buttons to indicate what direction the second intersection is from the first.

Before I go into how I did, two caveats. Kraemer's research is still in the pilot phase. He's only tested a couple dozen people, and he's like to test maybe three times that many for good comparative validity. Also, the tests themselves have been evolving (up to and beyond when I did them). For example, my "learning phase" included three looks at each city, whereas some folks only went through each route once, others twice. I was the first to get the benefit of a third time through. On the other hand, in the building ID tests, the view-twice group was shown pictures of buildings as they actually appeared during the city exploration (identical orientation, etc, rather than the whole building in isolation that I had to ID).

Here's something a little spooky. I was the only subject who tested as an equally visual and verbal learner, and I thought for sure the verbal would be advantaged. I'm also really close on the object-spatial distinction, with a slight (surprising) advantage to spatial.

There are some very interesting, albeit tentative findings regarding visual-verbal-spatial learners and how they performed on each of the three tasks. But Kraemer's asked me to hold off on publishing anything until he's run a lot more subjects through the same tasks. So, I'll just report my own performance.

1. In landmark ID accuracy, I was better than all but two subjects in the "view once" group, which Kraemer said was probably a more valid comparison due to the advantage the view-twice group had in that task. But, full disclosure: I was tied for worst performance among the view-twicers.


2. In the intersection test, I pretty much mopped the floor with the view-oncers (I was about 92 percent accurate, and second best was about 52 percent), and I beat all but two of the view-twicers.


3. In the pointing task, what researchers call the "judgement of relative direction," and what's considered the most spatial of all the tests, I was in the top three compared to all the view-oncers and in the top four compared to the view-twicers.

Sure, I was probably a more motivated subject than the average undergraduate in it for $20, and I'll await  the results from more subjects to see if the trend of my above average performance continues. But I really think there's something to ponder here--either these tasks aren't really testing the abilities and skills required for real-world wayfinding, or this is evidence to support my suspicion that, despite how frequently I get lost, I have a very good sense of direction somewhere inside me that just needs to be properly tapped.

Interesting sidenote: Among the view-twicers, there was one subject that kicked everyone's ass, scoring tops in all three tasks and pointing like GPS, getting 65 percent correct in the judgement of relative direction task where the average (among everybody else) was about 22 percent. I hit 27 percent, btw. And that's right, I said HER score. This doesn't by itself mean the gender differences in navigation are all bogus, but it does fly in the face of stereotype.

A Garden of Forking Paths

I'm compelled to mention that I spent my first five minutes in Providence yesterday walking circles around the train station trying to get my world to fit the Google Map print-out I had for directions to the VENLab. Once I found the place, I spent a few minutes with Bill Warren, who heads up this virtual reality navigation lab to go over the day's schedule. Then to the VENLab itself, which is a 50 by 50 foot converted chemistry lab, empty, until you put on the VR helmet.

I began the day as a subject in an experiment by doctoral student Liz Chrastil, who is testing the effects on navigation of active vs. passive learning. She has people learn to find objects in a virtual maze--some by walking, some in a wheelchair with no control, some in a wheelchair with some control (i.e. telling the researchers where to push them), and some simply watching a recorded video of somebody else exploring the maze. Then, she has them go from one object to another, either through the maze or directly with the maze shut off and replaced with a grey expanse of desert.

With the helmet secured, and a transmitter cinched around my waist, I sat in a wheelchair (my random draw was to be a passive learner) and looked out into a leafy green hedge maze. Below was a gravel path and above was an unblemished blue sky. Crickets chirped through the headphones I wore, interrupted frequently by Liz's recorded instructions. Unlike most hedge mazes, this one had famous works of art hung on its walls by Dali, Monet, Magritte, and Renoir. I glanced at them as I was whisked through the maze and brought before the various objects hidden in its branches--a pedestal sink, a giant stone gear, an old well, a floating Earth, a book case, a clock, and a statue of a rabbit frozen in mid-leap (like a bad day in Narnia).

I didn't get a chance to ask the researchers how they managed to push me through a maze that they can't see, but "managed" is an apt word in this case, because I was frequently thrust through walls by accident and given glimpses of the desert world beyond the maze. Also, there's a slight delay in virtual reality between the movement of one's head and the rendering of the images, which messes with your vestibular sense enough to make many people a little sea sick. Being pushed through such a world only adds to the fun. Clip a few walls while you're at it, and you quickly become much more engaged with your stomach than your place in Euclidian space.

I sound like I'm making excuses, and maybe I am. Truth is, I have no idea how much my simmering nausea in the learning phase affected my performance in the testing. Probably, enough people have the same trouble that it should all come out in the comparative wash. Anyway, I was given the short-cut task, repeatedly wheeled through the desert to a spot where the wishing well or the bookcase or the sink,  would appear momentarily when I stood up and clicked a mouse, and then disappear again. Liz's recorded voice would tell me a second object. My job was to turn through the desert in the direction I believed the second object to be and then walk there (well, shuffle there. balance is tough in the virtual world).

I'll admit, this task was very difficult. And sometimes a little terrifying: The VENLab is equipped with a system to warn subjects enjoying a shuffle through a sunny virtual world that they're about to walk into a very real brick wall. It goes like this: An image of a brick wall springs into view and a stern, robotic voice yells out, "STOP! STOP! STOP! STOP! STOP!"

Good idea, I've rambled on far too long here. I'll catch up on the rest of my VENLab visit in the next post.

Pushing on the pull door

Since I began my lab-ratting, I've been filling out a lot of "rate your own sense of direction" or "rate your own spatial abilities" questionnaires. There are usually a series of statements, such as, "I very easily get lost in a new city" or "When I'm in a complex building, I can easily visualize what's outside the building in the direction I'm looking" and then you are asked to answer with varying levels of agreement ranging from strong agreement to strong disagreement.

Here's one of my favorites: "I always know if a chair will fit through my front door before buying it." Now, I've never bought a chair so large that there was any doubt that it would fit through my front door. But I do have experience trying to move a massive armoire into a second-floor apartment I was sharing with my sister. We had three people pushing and lifting, but the thing got stuck at a turn in the stairs. We managed to inch it up and forward through a series of twisting, lurching and cursing maneuvers, but after half an hour or so, we knew we were beaten. Then the real trouble started, because by this point we couldn't get it down the stairs either. It was pinned. We phoned an extra large friend for emergency help. He arrived just in time before my sister went to find an axe.

Here's another one: "It's not important to me to know where I am." It must be nice. But then again, aren't you curious?

And one more: "I enjoy reading maps." I do. I love maps. I like reading maps so much that I look at maps of places where I have no prospect of ever going. Likewise, I love historical maps (in the case of Boston, I like tracing the streets that once were bays, busy with merchant ships; I like to imagine the farm that was cut up in the late 1800s to create my neighborhood). Yet, I still get lost all the time. And my suspicion is that the assumption behind this question is that the more you enjoy maps, the more spatially oriented you are generally. So, it makes me wonder...

On and Off the Grid

I'll be making a return visit to the VEN (Virtual Reality Environment) Lab at Brown University tomorrow. Bill Warren, department chair and professor of cognitive and linguistic sciences, heads up the lab. He was kind enough to let me don the VR headgear and explore the virtual worlds of his lab back in 2003 for a Boston Globe feature I wrote on navigation research (my initiation into this research). Lucky for me, I had a researcher "wrangler" following me around while I explored to keep my feet clear of the wires connecting the VR headgear to the computers, and keep my face clear of oncoming brick walls.

Since 1999, Warren has used these virtual worlds to investigate all aspects of how humans "path integrate" (i.e. how well we track our own distance and direction over time as we move, independent of landmarks). A really good path integrator should be able to follow a circuitous path and take a shortcut back "home" and should, after enough exploration, start developing an accurate sense of how far and in what direction any location in an environment is from any other--in short, a Euclidian cognitive map.

A common test of path integration skill is to have people walk two legs of a triangle in a virtual desert, then have them turn and walk the third leg back to the starting point without any visual aids. After that, the researchers often start messing around... adding landmarks to see if that changes anything, and then moving landmarks to see if you notice, etc.

Generally, Warren has found humans to be pretty bad at path integrating. Recently, he's taken aim at the theory that we're ever capable of building up a Euclidian cognitive map. He's had people learn locations and routes in a virtual hedge maze and then secretly introduced "wormholes" within the maze that magically transport people to those locations. A Euclidian cognitive map would cry foul at such geometric dislocation, says Warren, but "nobody has found anything amiss."

Tomorrow, Warren will show me the wormholes. I'll also continue trying to diagnose my own sense of direction with the help of post-doc Mintao Zhao who is looking into what happens when path-integration and landmarks compete and with doctoral student Liz Chrastil who will run me through a battery of basic skills tests and have me take part in her active-vs-passive learning experiments.

Philly, Back Again

I'm late with this post, but the few days since my return from Philly have been crazy, so I'm just getting to it. I spent my second day with the navigation researchers taking part in a truncated version of an experiment they've been running to test if and how people of differing navigational abilities improve on a wayfinding task over time.

We traveled to a satellite campus of Temple University about 50 miles north of Philly early last Thursday morning. Once there, I waited by the car while the researchers, Victor Schinazi of Penn and Dan Nardi of Temple, went off to set things up. They returned with a wheelchair, a blindfold, and a portable radio with headphones. All of it was for me--once in the chair, blindfolded, and oblivious to all sound but the grunge rock radio station, I was wheeled in circles to disorient me and then pushed through the campus. I was released at the starting point of "route one," a fairly short, albeit circuitous path (about two tenths of a mile, I'd guess) connecting four buildings that I was told to learn as we walked. I was then summoned back into my dark, Nirvana-fueled wheelchair, spun in circles again, then pushed to another part of campus where we arrived a few minutes later to walk "route two."

After that, it was back into the dark, Alice in Chains, more spinning, and a return to route one. This time, at each building, Victor and Dan told me to point to every other building in this route and in the unseen route two, and they checked my pointing with an electronic compass. My pointing had to be stiff armed and straight-fingered (Grim Reaperish) to ensure an accurate compass reading. I have no idea what the groups of passing students thought of our little group, but I'll never forget the looks as I arose from my wheelchair and began pointing (seemingly) at several of them.

Ok, so, then: dark, Soundgarden, spinning, route two, and the same walking and pointing task. After all this, I was wheeled back to a mystery room and asked to close my eyes and pretend I was walking both routes, pointing all the while. Finally, a very long questionnaire that asked me to judge the distances between all the buildings in each route.

After lunch, we started phase two (which in the normal experiment would happen a week later). Victor and Dan showed me a curving connector path between the two routes. Then we did all the rolling, spinning, pointing stuff again at both routes, the imaginary route pointing, and the questionnaire. Normal subjects would return for a third go-round, at which time they would be shown a second connecting route. Another part of the research I skipped due to time constraints is the follow-up fMRI.

Anyway, the point of all this is to see if and how people improve from one trial to the next. It builds on a very similar experiment conducted a few years ago by Daniel Montello and Toru Ishikawa who found that subjects broke into three groups--some improved steadily, but "most participants either manifested accurate metric knowledge from the first session or never manifested accurate metric knowledge." In other words, their findings indicated that for the majority of us, when it comes to navigational acumen, you either got it or you don't. 

Victor and Dan screened their subjects to make sure they have never been to this campus and promise to refrain from investigating it independently. And in the first trial, navigation performance is all over the place. Some people are weirdly, shockingly accurate with their pointing and distance estimations. Others make errors that defy basic logic. In deference to their yet-to-be-published data, I won't reveal more about what Dan and Victor have found. But I will as soon as everything is in press and I have the chance to get their comparative analysis of my own pointing performance.

My mind hurts

This is going to be a short post. I need to write it, but I have the brain power of a turnip right now, so I won't go into detail. I've just returned from a 9-hour day of navigation testing at the University of Pennsylvania. Fittingly, the day began with me marching seven blocks in the wrong direction while trying to walk from my bed-and-breakfast to Penn's Center for Cognitive Neuroscience

Still, after I found the place and met my gracious researcher hosts, I tested quite well. I spent a very long time learning my way around eight virtual cities in two different experiments and then took my turn in the MRI. I had imagined an MRI to sound like a photocopy machine, whirring reassuringly as it scanned the brain. It's actually a little like being trapped under the hood of a car when the alarm is blaring. On the plus side, I was able to see a few of the scans immediately afterward, giving me the first piece of hard evidence on this odyssey: I do in fact have a brain.

Another day of testing tomorrow, but thankfully most of it is outdoors. No computers. No floating through the fantastic, virtual ghost towns. No super-charged magnetic sarcophagus.

I'll supply more detail on my lab-rat day and get into the science of all this soon.

Testing 1,2,3

In a few days, I leave for Philadelphia where some navigation researchers from the University of Pennsylvania and Temple University will do their best to diagnose my sense of direction. The tricky part is that most labs investigating human wayfinding aren't set up to evaluate individuals. They focus on how the mind reacts to certain navigational cues, what brain areas are activated, and what benefits or impedes our spatial ability generally, and research into the how and why of individual sense-of-direction differences is in its infancy.

But these folks in Philly have agreed to run various tests on me (some real-world navigation, a bit of virtual reality, some paper and pencil stuff, and an fMRI) and to compare my performance and my brain activation to the rest of their study subjects. I also have more lab-rat dates lined up for later this spring. Can't wait.

Is GPS killing your brain?

I called up Toru Ishikawa, a navigation researcher at the University of Tokyo, last night (the next morning for him). We talked about his research into how GPS affects our ability to learn our way around a new place. Two years ago, he had about 60 men and women learn a short route through a residential suburb of Tokyo--one third with no navigational aid, one third with paper maps, and one third with GPS. Then he tested them (asked them to travel the route independently and timed them, had them point from their destination back to where they started the journey, had them draw sketch maps of the route, etc). On almost every metric, those who learned au naturale kicked ass. In the test phase, they navigated the route faster and more efficiently (fewer wrong turns), drew more accurate maps, and later rated the task easier than those who used GPS. The map users couldn't match them either, although they did better than the GPS group on many of the scores.

What's this mean? It could be evidence that GPS is melting our brains and we should all stop using them before we turn into zombies who can get from here to there but have no idea where here or there is (or anything in between). There have been similar questions about how the Web (specifically Google) may be changing how we think (and not for the better). But let me venture to say that these experiments are not going to spark any such cultural backlash. There are too many people who love the convenience of these gizmos, and others who would never venture out of the house without them.

So, maybe GPS navigation systems should just be designed differently--possibly using a variety of graphics or voice commands--something that might reinforce our navigational synapses rather than short-circuiting them. Or maybe, GPS will be whatever it will be and this type of research will simply document its neurological impact and provide more evidence that every navigational aid we've introduced over the millennia (from big buildings to street signs to Google Maps) has permanently eroded our innate wayfinding abilities. This idea, of course, raises the question of whether this is an evolutionary change, some permanent rewiring of our brains, or if we could resurrect those abilities with "training."

Personally, I've never used a GPS and I'm in no hurry to get one (no one would call me an "early adopter" but I'm no luddite either). No doubt, I'd have an easier time driving to new places with a GPS. But I feel like I'd lose something, too, and not just the more durable route knowledge that Ishikawa investigates. There's more than easy navigation to be gained from looking around you, studying what's passing by as you drive, and even from the occasional wrong turn.

Not just where, but why?

I'm five posts into this blog, and I haven't yet explained myself.

In my family, I'm known as the one who gets lost. My dad, who used to sell steel all over the world, would wander around Karachi, Dacca, and Mumbai the day he arrived and take shortcuts back to his hotel. My brother, separated from the rest of us in a mall at age two, found his way back to our car and sat on the hood to await his frantic family. My mom and sister have no such navigational boasts that I know of, but neither do they get lost the way I get lost (habitually, spectacularly). I won't waste time cataloguing the scenes of my woeful wayfinding but they range from the Mojave Desert to the stacks of my college library. And don't get me started on driving in Boston.

Here's the weirdest part. Despite all the wrong turns and misadventures, I suspect I might actually have a superb sense of direction that I haven't properly tapped. So, I'm on a mission to find out. Along the way, I'll dig into the mysteries of this curious cognitive skill--what it is, where it comes from, and why we feel its absence in our bones.

Free to be you and me

Speaking of Thomas Wolbers (see previous post). He's a co-author (with Mary Hegarty ) of an article in the current issue of Trends in Cognitive Sciences that lays out a model for investigating why some of us are hardly ever lost while others of us, ahem, have the sense of direction of a loaf of bread. The paper, "What determines our navigational abilities" uses existing literature on human navigation experiments to develop this three part model: Here, we consider three interdependent domains that have been related to navigational abilities: cognitive and perceptual factors, neural information processing and variability in brain microstructure. Loosely translated, that means future investigations of "why" our wayfinding abilities vary so much should focus on the sharpness of our sensory perception, the efficiency of our brain's wiring which collects and integrates all that input, including memory, into a "mental map" and the brain areas activated when those mental maps are used by navigators of varying abilities. 

I don't want to get into any copyright trouble here by posting the whole article, but I think a couple of the boxes are well worth the risk, because As Wolbers and Hegarty note, the individual differences model they propose focuses on internal, neuro-cognitive differences, rather than the nature-nurture questions that might underly them. But the boxes bring up some of these issues:

Sex differences

There have now been several demonstrations of a human male advantage in virtual maze tasks and in spatial learning from navigational experience [11,14,19,53,54], somewhat paralleling sex differences in animal species [55]. 


Although sex differences are sometimes more pronounced when tested in simulated environments [14,54], they occur with testing in both real and virtual environments [56] and when the analyses control for video game experience that is often greater in males than in females [19]. Superior performance by males is not found in all tasks at the environmental scale. It is typical when people learn spatial layout from direct experience, but not when they learn from maps, and is also more pronounced in measures of survey knowledge than in measures of route knowledge [53,56]. Furthermore, female performance can vary with hormonal fluctuations, such that women can perform as well as males during low-estrogen stages of their cycle [57]. Object location memory often shows an advantage in favor of females, although this can depend on the type of objects, whether self-motion is involved, and the degree of metric precision required [58,59].

Intriguingly, there appear to be qualitative differences in the environmental cues and strategies that women and men use during navigation and orientation. Women typically report navigating on the basis of local landmarks and familiar routes, whereas men report using cardinal directions, environmental geometry and metric distances [60,61], a result which has been supported by neuroimaging findings [62]. 


Although women do not differ from men in dependence on or ability to use landmarks, they depend less on geometry when reorienting to an environment [11] and are relatively more impaired at finding a target based on directional cues (i.e. environmental slope, [60]). Women also require more environmental cues to remain oriented in an environment [10] and have difficulty following navigation directions based on cardinal directions and metric distances [21]. 


Thus, strategy preferences can reflect proficiency differences between the sexes in use of geometric cues, as well as relative cue salience. In terms of causal factors, there is increasing evidence for the influence of sex hormones on navigational performance [25,57,63–65], and several evolutionary theories have been proposed [66]. However, men and women also differ in navigational experience [54,67] and there is some evidence that wayfinding anxiety mediates the differences between the sexes in navigational performance [67].

And this one:

The impact of genetic factors 


The structural and functional integrity of neuronal circuits is jointly determined by environmental and physiological factors, the latter including genetic predispositions. Genetic association studies in animals have demonstrated various genetic influences on hippocampal processes involved in spatial navigation [78]. Specific examples include the brain derived neurotrophic factor (BDNF) that is known for its role in activity-dependent plasticity and hippocampal long-term potentiation. 


Both processes are thought to underlie the formation of new learning and memories, and suppression of BDNF synthesis impairs spatial learning in rodents [79]. Although direct effects of BDNF on human navigational learning remain to be established, BDNF modulation of hippocampal engagement is a key process in the initial acquisition of information about novel indoor and outdoor scenes [80]. In addition, polymorphisms of the BDNF gene have also been associated with hippocampal volume [81], which could contribute to preferences for specific strategies in a navigational task [46].

A second route for genetic predispositions to affect hippocampal processing and hence navigational abilities involves pattern separation. To distinguish between environments or regions within an environment, hippocampal subfields create orthogonal representations [82]. This ability to pattern separate is directly related to neurogenesis in the dentate gyrus, which is in turn controlled by several genes [83]. Given that ablation of pattern separation in mice induces deficits in spatial learning in a radial arm maze [84], it appears probable that individual genetic predispositions that control hippocampal neurogenesis can have direct effects on

navigational abilities via differences in pattern separation. 


Finally, as spatial navigation also involves executive control processes that involve subdivisions of the prefrontal cortex [33,85], genes that regulate prefrontal functioning should have the potential to influence navigational abilities. For example, given the dopaminergic metabolism in the prefrontal cortex, the gene producing catechol-O-methyltransferase (COMT) is thought to have a major impact on functions such as the manipulation of information [86] and the resolution of uncertainty [87], both of which are involved in spatial navigation. Moreover, COMT polymorphisms also affect prefrontal–hippocampal coupling [88], which is crucial for navigational planning [35].

Taken together, although the existing animal findings strongly suggest genetic influences on navigational abilities, a direct demonstration remains to be established in humans. Given the complexity of spatial navigation, genetic variability is likely to affect navigational functions at multiple processing stages.

Wired for Wayfinding

A friend sent me this recent post on msnbc.com's Body Odd  blog. I've only heard of one other search for human wayfinding genes, a genome-wide association study by Thomas Wolbers at the University of Edinburgh (no published results yet from that study, as far as I know), but I'll bet we see many more such studies soon:

Always lost? It may be in your genes

Posted on Wednesday, March 03, 2010 2:58 PM PT

By Kavita Varma-White, contributor

When it comes to navigation skills, some of us are homing pigeons. Others
are mice in a maze.

The sharp navigators are those who can figure out which way they need to
go in an unfamiliar setting to get to their destination. No GPS needed to
find their way around town. No always stopping for directions. Some folks,
meanwhile, are hopelessly disoriented  — the type that gets lost in a paper
bag.

A new study suggests that skillful navigation just may be in your genes.

Say you are in a city — Washington D.C., for example — and you
emerge from a Metro station to walk to a specific destination. For a
minute you feel discombobulated. But, glancing around, you see the
Capitol building, and a layout of surrounding streets helps you pinpoint
your location. What if the landmark and roads didn't help?

Previous scientific research suggests that humans, rats, chicks, chimps
and even fish use geometry to reorient themselves in space . They
mentally visualize the geometry of their surroundings — corners and
walls — to figure out where they are. But the new study indicates that
genes may play a part in that ability.

The new study, conducted by lead author Laura Lakusta, an assistant
professor of psychology at Montclair State University, 
Barbara Landau, the Dick and Lydia Todd Professor of Cognitive
Science at the Johns Hopkins University, and Banchiamlack 
Dessalegn, a postdoctoral fellow at the University of Chicago,
compared the navigation skills of normally developed adults and
children with people who have Williams syndrome.

"We found that people who suffer from the genetic disorder Williams 
syndrome have trouble reorienting themselves, a basic process that
is shared among human children and adults, and a variety of 

non-human species," Lakusta said. "Our finding that individuals with
Williams syndrome show this kind of impairment suggests an
important link between genes and the system that is used for
reorientation."

Williams syndrome, a rare condition which occurs in one in 7,500
people, is caused when a small amount of genetic material is missing
from one human chromosome. Individuals with Williams syndrome
have strong language skills and are extremely social, but they have
trouble with tasks like doing puzzles or copying patterns or navigating
their bodies through the physical world.

In the study, Lakusta and her team challenged individuals with
Williams syndrome to find a hidden toy in a rectangular room. The
room had two long walls and two short walls and was covered in black
felt. The Williams syndrome individuals were shown the toy and where
it was hidden in one corner of a room. They were asked to close their
eyes and were rotated for a few seconds. Then they were asked to find 

the toy.

When looking for the object, the Williams syndrome individuals — who
were both male and female ranging from age 9 to 27, "searched all the
corners randomly," Lakusta said, as if they had never before seen the
overall geometry of the room or the lengths of the walls and their
geometric relation to each other.

When testing a group of college students and a group of 3- and 4-year
olds who did not have Williams syndrome, Lakusta and her team found
a more typical pattern of responding.

"If we hid the toy left of the short wall and right of the long wall, they
could mentally construct an image of the room and find it, even if they
became disoriented. They would tend to search the geometrically
appropriate corner. They could figure out that there are two corners
where the toy could be. This is the geometric pattern of responding,"
Lakusta said.

"The Williams syndrome subjects could not construct a mental map of
the geometry of the environment," she said.

The study was recently published in the online Early Edition of the
Proceedings of the National Academy of Sciences.

While other research studies have suggested a link that certain brain
areas might be responsible for the behavior of reorienting, there has
been no evidence that it might be linked to a specific gene, Lakusta 

said. "Now we know that, in general, genes can be deleted and we could
see this impairment of orientation."

For those who are navigationally-impaired, this kind of research is a small
but important step in understanding why you may have a hard time getting
where you need to be.

Of Mice and Men (and Women)

Big navigation news out of University College London. In last month's Nature, a group of UCL researchers wrote that they'd found evidence of "grid cells" in the human brain. Scientists have known for a while that rodent brains have these "grid cells," whose accumulated firings map a triangular grid as the animal explores an open area.  They are just one of several specialized navigation neurons that have been found in rats, mice, and a few other animals.

But we don't know as much about our own navigational wiring. After all, opportunities to poke around living human brains are rare, although a few years ago, researchers at the University of Pennsylvania found a way. They asked a group of people with epilepsy who already had electrodes in their brains to identify the source of their seizures to play a taxi video game, providing the researchers with a neural play by play. 

In 2003, the Penn researchers found "place cells," neurons that fired only in response to seeing a given place (e.g. a bookstore), and cells that fired only when arriving at that bookstore, and still other cells that fired only when that bookstore was the virtual cabbie's destination. Two years ago, they discovered heading-specific "path cells" whose activity indicated whether the taxis were steering clockwise or counterclockwise around the virtual town square. But the search for "grid cells" by the Penn researchers and other labs had come up empty. Until now.

"Travel Directions" by Joan Siegel

There ought to be a word
for the way you know how to get some place
but don't remember the names of streets
the number of turns and blinking yellow lights
so that if someone asked
you really couldn't say
except you know the road starts out straight
and when it's sunny the branches blink across
the windshield making you want to rub your eyes
then the road turns sharply uphill past a red barn
where a black dog jumps out to race you for a quarter mile
and finally recedes in the mirror like a disappointment
and you remember the road dips downhill
into the shadows of the morning
where you hear Bach's unaccompanied 'cello
and understand what a good fit the 'cello makes
in the hollow of the body
where grief begins and for an indeterminate time
the road winds vaguely past
houses    people    road signs
while time hums in your ear and you remember
the dream you left behind that morning
which had nothing
to do with where
you are going

"Travel Directions" by Joan I. Siegel, from Hyacinth for the Soul. © Deerbrook Editions, 2009.

Two family member independently sent me this poem the other day when Garrison Keillor read it on the February 24, 2010 "Writer's Almanac ." Listen to it here (preceded by birthday announcements, of course). It made me think of the directions to the freeway given to Clark Griswold in "Vacation":

You go half a block down the street...

...and you'll see a Torino
with no wheels on it.

Inside that Torino is my cousin, Jackie.

Tell him that you're my boy,
and that you're lost.
                  
He'll make sure you
get where you're going.
                   
You don't want to know from me.
I'm not from this neighborhood.

I'm from the west side of Chicago,
here on vacation.