Cognitive Daily

Which of these two pictures is more memorable?


ResearchBlogging.orgThe shot on the left is interesting primarily because Nora’s in it — if it was just a picture of a muddy trail, it wouldn’t be notable at all to most people. The shot on the right is a dramatic mountain scene that you might remember even though (or perhaps because) there’s not a human in sight.

But a seasoned hiker might be more interested in the photo of the muddy trail, which gives more information about the difficulty of the hike than a panoramic shot. Just as expert chess players are good at remembering the position of chess pieces on the board, maybe expert hikers are better at remembering details about trails than novice hikers.

The classic study of expert and novice chess players was conducted in 1973 by William Chase and Herbert Simon, and found that chess experts could remember configuration of chess boards better than novices — as long as the chess pieces were arranged in a plausible game configuration, and not just randomly arrayed.

Since then, dozens of studies have found that experts in a variety of fields have better memory for things related to their area of expertise, from football formations to chest X-rays. But according to a research team led by Satoru Kawamura, all of these results can be explained by perceptual chunking: Experts are better than novices at lumping information into manageable groups. Hiking scenes, they argue, aren’t easily chunked in the same way. Do expert hikers still have better memory for scenes relevant to hiking?

The researchers showed 35 hikers a set of 30 pictures — one at a time, for 2 seconds each — and asked them to imagine they were progressing on a hike and to try to remember the pictures for a recall test later on. Half of the hikers were experts who had more than four years of experience and had served as group leaders on hikes. The others were novices, averaging just 1.2 years of experience. Half the pictures depicted important functional features of the trail (river crossings, ladders, fallen trees). The other pictures just showed scenery along the hike (waterfalls, views, or easy, wide trail).

After viewing the pictures, they were distracted for several minutes with a math quiz. Finally they were tested with a set of 60 pictures: the 30 originals plus 30 distractors from the same hike. Respondents had to indicate whether they had seen the pictures before. Did the experts remember more pictures than novices? Here are the results:


This graph combines the results for correct responses and false alarms (more correct and fewer false alarms leads to a higher d’ value). For low-functionality scenes, there was no significant difference between expert and novice hikers. But for high-functionality scenes, experts scored significantly higher than novices. Even after controlling for the older age of the more experienced hikers, the effect persisted.

Kawamura’s team says this study demonstrates that better expert memory for scenes in their field of expertise isn’t just due to chunking. Perhaps experts simply devote more attention to the scenes that give them more important information.

I can say that I still have very distinct memories of the muddy trail on that hike with Nora, while I only remembered the particular scene in the second photo when I was going through my pictures to find an illustration for this post. Whatever the mechanism, my anecdotal experience as a hiker is that I remember difficult trails better than the particular scenery of a hike.

Kawamura, S., Suzuki, S., Morikawa, K. (2007). Short report: The effect of expertise in hiking on recognition memory for mountain scenes. Memory, 15(7), 768-775. DOI: 10.1080/09658210701582315


  1. #1 Greg
    February 13, 2008

    The left-hand picture is much more interesting and memorable for 2 reasons:
    1. It has a human in it. (Not to get sentimental; an animal or striking piece of vegetation would also have the same effect.)

    2. It has an immediacy and less-than-perfect appearance than the right-hand image. The latter has obviously been Photoshopped (or edited & airbrushed, and color-corrected in a similar program) and looks like millions of “pretty” forgettable picture postcards.

  2. #2 Luna_the_cat
    February 13, 2008

    I disagree that the picture on the right looks airbrushed, but that’s beside the point.

    Yes, it’s definitely attentional. The picture on the left not only involves an area of expertise, it also involves a situation you might have to deal with physically. You aren’t just looking — you are evaluating potential actions. I’m not in the least surprised that we remember in more detail, later.

  3. #3 Dave Munger
    February 13, 2008


    Actually the second photo wasn’t photoshopped at all. I was actually thinking I should do something to reduce the contrast in the shadow at the bottom of the frame, but in the end I decided not to bother.

    As you say, the main reason you find the photo on the left more memorable is because it’s got a person in it. In the actual study, none of the photos had people in them. I couldn’t find any pictures of difficult among my hiking photos that didn’t also have people in them.

  4. #4 Dave Munger
    February 13, 2008

    I’m not in the least surprised that we remember in more detail, later.

    Just curious: are you surprised that non-experts don’t?

  5. #5 Ahcuah
    February 13, 2008

    I do a lot of hiking. A few thoughts . . .

    As I think back over various hikes I’ve made, it’s the trail details that I recall most easily. In fact, for many of them, it is the intersections that come back more clearly for me–that’s of course important information for not getting lost. But with fairly little effort I can recall details on all sorts of trails I’ve hiked in the last year or two. By the way, in that recall, I find that I recall trails that I’ve traversed twice seem to be recalled much better (maybe more than twice as good) as those I’ve done only once. I wonder if there is a way to re-do the study allowing a couple of multiple visits and seeing if that re-inforces the difference between the two sorts of views.

    About the only “scenery” images that come back readily for me was one extraordinary one a few years back when it started snowing and the snow partially masked an adjacent ridgetop, and a spot that had been clear-cut (that comes back, I suspect, from the disgust that registered at the time–ugly emotions come back more readily).

    While I cannot remember precisely, I do think my focus has changed in this regard over the years and I have gotten more experienced.

    One more comment. I hike with my dog, and I will often go cross-country following nothing more than a deer trail, or a very old trail that is rarely used. For my last two dogs, I have noticed that, when they are younger, 4 years or less, they are worthless in following the trails that have mostly died out. However, they too seem to learn, because for both of them, once they hit the age of 5 of so, I could reliably trust them to go first and to show me the barely visible correct path.

  6. #6 Drekab
    February 13, 2008

    It might be interesting to send people on a hike and later test how well they can match photos of the trail to a map of the trail. That might give some more data on what it is that people are paying attention to.

  7. #7 Freiddie
    February 13, 2008

    It’s a little hard to discern what your immediate environment in the second picture. It’s as if you took that photo from a floating helicopter, rather than during a hike. That might be a reason. So more of a vista than a picture of your surroundings. Perhaps that “unnaturalness” is why you don’t remember the second photo. Just thinking.

  8. #8 M.
    February 14, 2008

    It’s a question of narrative; I would imagine that the people who are expert hikers are able to recall significant portions of their hikes, but not necessarily in the correct order, like people who remember long oral narratives. They group important details of their hike, such as choices in the path, significant points of rest/refreshment, transitions in difficulty, etc. into single “trail narratives”. Showing them the pictures seems, from the success rates in the data, to correspond to the kind of questions of stories that you might find in oral narrative, i.e., imagine trying to identify a story from details as such “a woman marries a prince” (many stories) “a woman cleans a house against her will” (many stories), “a woman has a step-parent” (many stories), “a woman needs a glass slipper” (singular detail [Cinderella]). While the order of details (in other words, the specificity of remember resolution) is arbitrary between points two and three, the overall narrative needs one to come first and the fourth, fourth, and to include two and three.

    It also has the benefit of being a minimal explanation, in that it uses a recognized cognitive structure to explain an analogous situation.


  9. #9 Kevin
    February 14, 2008

    Interesting study. I think it would have been much stronger paper if they hand included a third group that had no hiking experience at all.

  10. #10 Marc
    February 14, 2008

    I’d be interested to see if this just applied to where you spend most of your time. People that live/grew up in cities would be worse at remembering outdoor scenes and vice-versa. So expertise, to some extent, but it doesn’t have to do with being a better hiker. It is a cultural difference.

  11. #11 ScienceWoman
    February 14, 2008

    But nobody has asked the important questions yet: Where are these two pictures taken? And how do I get there?

  12. #12 Dave Munger
    February 14, 2008

    Good question!

    The first picture is on the Clingman’s Dome trail in the Great Smoky Mountains National Park in North Carolina.

    The second picture is in the Glacier Peak Wilderness in Washington.

  13. #13 Luna_the_cat
    February 15, 2008

    I’m not in the least surprised that we remember in more detail, later.

    Just curious: are you surprised that non-experts don’t?

    Hm…not sure. Maybe. To me that would be, do the non-experts look at it as “just another picture”, or do they look at it in the context of “If I were on the trail what would I do here” — that simply attitude/personal involvement issue might be more important than expertise per se.

  14. #14 Tracy W
    February 18, 2008

    That’s odd. As a hiker, I would say that the panoramic shot is important because it tells you were you are (assuming you can recognise the mountain in the middle of course, which I can’t). It also tells you what the weather conditions are like.

    Flicking back through my memories of hikes, I have quite a few memories of gazing around at landscapes, trying to figure out which direction I am facing, and what spur I am on, and what the clouds and the wind are doing.

    I think I remember scenic views even more when I am particularly worried about one or more of those details. I remember a bit of route-finding on the tops of the Kaimanawas from which I have a lot of recollections of the views.

  15. #15 John
    February 19, 2008

    I know neither of those two pictures are from the Appalachian Trail because I remember every inch of it and neither are familiar. 😉

  16. #16 John
    February 26, 2008

    It seems that, while chuncking-mechanisms might be more difficult to conceptualize for hikers, there is no reason to rule out chunking as a possible explanation for better memory. It could be that hikers see patterns of features in these photographs that they chunk meaningfully. Am I missing something?

  17. #17 Dave F
    February 26, 2008

    I don’t think this experiment properly tested expert hikers
    memory. There is really no additional information to be gained
    by traveling (‘flying’) through a 3-D recreation of a chess
    set. On the other hand, the amount of information to be gained
    by a single 5 yard walk through real terrain (where you do not turn
    your head even) can not be boiled down to a single narrow
    one dimensional photo. The amount of useful information
    gained by passing through a 3-D terrain as opposed to looking
    at a 2-D photo should not be underestimated.

    I have actually remembered a cross roads while driving (not hiking)
    on a road I had never been
    on before. I was somewhat lost at the time, and was not really
    looking for this intersection, even though I had passed through the intersecion a single time
    a decade earlier on the intersecting road (90 degrees). There was
    not some extraordinary landmark there, unique to the location.
    It had to be the ‘gestault’ of the location which made it unique
    to my mind.

    That just astonished me!

    I beleive this is related to having a good sense of direction.
    Although I have a better sense of direction than most, my Dad’s
    is even better, it is not clear to me that this is completely
    a learned ability.

    As for dog stories, I too like to bushwack and off-trail wander.
    I realized when a new 2-3 month old puppy was leading me down a
    faint forest trail she had never been on that this ability is like
    language, its genetically encoded, not learned.
    Computer researchers even 10 years ago were still
    struggling to get a computer to realiably visually
    follow lanes on a divided highway with stripes shoulders
    and everything, and yet a little puppy (who does not have
    a very good nose, she is visually oriented)
    can visually follow a faint forest track.

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