Visuospatial processing, the sense of direction, reality and virtual reality

A few years ago, each of my adolescent kids was invited with his classmates to a "navigation day", organized by the youth movement and the parent association.  We live in a small community with an infrequent bus schedule.  The rational for this navigation day:  "We drive our kids everywhere, thus they don't develop independence and don't know how to get from place to place on their own and using public transportation.  The purpose of this day is to train   these skills."

A few days ago I happened to read this short piece by JULIE LYTHCOTT HAIMS, a former dean of Stanford University.  Haims mentions eight must- have skills for every 18 year old.  One of the skills is this: "An 18-year-old must be able to find his or her way around a campus, the town in which her summer internship is located, or the city where he is working or studying abroad.  We drive or accompany our children everywhere, even when a bus, their bicycle, or their own feet could get them there; thus, kids don’t know the route for getting from here to there, how to cope with transportation options and snafus, when and how to fill the car with gas, or how to make and execute transportation plans." 

I get the feeling that this is typical of adolescents and young people from good SES background in Western societies…  Lack of navigational experience not only affects a person's independence and ability to get from here to there, but also his ability to create a cognitive map of his near and far surrounding.  Cognitive maps form through active interaction with the environment.    When an adolescent sits at the back sit of the car, looks passively out of the window or, worse, looks at his cellular, the cognitive map created in his mind is far poorer than when he navigates actively.  The problem is not only with adolescents who don't have a driving licence.  When a driver uses GPS, especially if he does it "blindly", his ability to create a cognitive map of his surrounding is badly affected.  In both cases, the adolescent's and the driver's, the mental representation created is mainly of two "dots" – the starting point and the destination point.  The space between these points is not mentally represented or is represented poorly. 

Maguire et al found a correlation between the hippocampus volume of London taxi drivers and their experience on the job. The more experience a person had as a taxi driver, the larger was his hippocampus.  This was in contrast with London bus drivers, who had no correlation between hippocampus size and experience at the job.  While taxi drivers have to navigate to different and new destinations all the time, bus drivers drive on the same known and practiced route.  These studies were done in 2000 and 2006, before GPS use was widespread.

Several researchers have argued that navigating with GPS devices supports only a reduced, disembodied understanding of landscape, hinders the development of cognitive maps, and results in poor reconstruction and memory of the environment through which one is driving.  The GPS relieves the driver of the need to plan his route (or to retrieve a route from memory), to pay careful attention to his surrounding in order to look for landmarks that match the planned route (salient objects, road signs etc.), to monitor his present location compared with the target location and his progress towards the target location, to correct navigation mistakes and to store the route in memory for future use.  Using GPS reduces the driver's active involvement with the surrounding environment.  Thanks to GPS, “engaging with the environment becomes a matter of choice”.

On a philosophical note, Yi-Fu Tuan, a cultural geographer, defines space and place in relation to each other: What begins as undifferentiated space becomes place as we get to know it better and endow it with value. […] From the security and stability of place we are aware of the openness, freedom, and threat of space, and vice versa. "   Does GPS hinder our ability to turn our route from "space" to "place"?

 Obviously, for people with significant navigation difficulties and with a poor sense of direction, the GPS is a lifesaver.  It also enables us to discover facts about our route's surrounding that we would not have discovered otherwise (for instance, the location of restaurants along the route). 

The ability to maintain a sense of direction and of place as we move in our surrounding is a basic cognitive ability.  Navigating in space enables us to find our way in complex surroundings (a trail in nature, but also an airport, a campus, a shopping mall, an elementary school, high school).  We can think about the experience of a first grade child, who moves from the small surrounding of the kindergarten to a much larger and much more complex surrounding of the elementary school (at least in Israel).  Do we think enough about this aspect of school readiness? How important is it to let the child know and find his way in the space in which he is going to study – before the beginning of the school year?

When lesions to the brain impair navigational abilities, patients often experience devastating effects on their everyday lives.  Given its complexity, it is not surprising that humans differ widely in their navigational abilities.    Variability in navigational abilities can arise at multiple stages of the process, including the precision with which spatial information is encoded from sensory experiences, the ability to form spatial representations of external environments and the efficacy with which they are used to guide navigational behavior.   There are individual differences in perspective taking ability (the ability to perceive depth and distance).  There are individual differences in size perception and estimation (these are related to mathematical ability).  There are individual differences in the sense of direction (a person's ability to monitor the spatial direction his head is pointing to).  We can estimate a child's sense of direction when we ask him, when he is in the psychologist's room, to point at the direction of his class, his home etc.

A child's ability to navigate is affected both by genetic factors and by environmental factors like parental guidance and exposure to maps.  Thus it can be improved.  The more active a person's interaction with his environment is, the deeper his visuospatial processing will be.

 You may have noticed that when you drive around in your car, even in a highly scenic environment, and stop in viewpoints, you don't enjoy yourself as much as when you hike in the same surrounding. There's no doubt that physical effort adds to the enjoyment, there's no doubt that finishing a trail gives one a sense of closure and accomplishment, but it may be that walking enables us to create a more detailed cognitive map of the surrounding, which gives us a good feeling of "mastery".

When we reach specific sites abroad, sometimes one of my children announces:  "I've been here in/with google earth".  What's the difference between visiting a place physically and visiting it virtually?  Beyond the multisensory experience of the real thing, when we are actually there we experience the site in its physical context, we understand better how it "connects" with the surrounding city or other sites in the area.

Is it a new – old role of the school at our age?  To take children on navigation trips?  To teach them to find their way around?  Is it easier to read a map, to study Geography, when you navigate with a map?  When you create your own map of your physical environment?

Many studies of individual differences in spatial ability have focused on smaller-scale tasks that involve simple object transformations (i.e. mental rotation).  Do these abilities predict individual differences at large scale navigation? A recent review of 12 studies found that the median correlation between the two kinds of tasks exceeded 0.3 only in two studies, and the majority of correlations were not statistically significant.  Navigation in the real world also involves the sensing of self-motion for the purpose of spatial updating and path integration, an ability that cannot be measured with simple object-based tasks in which self-motion cues  are neither available nor task-relevant.

Leshed, G., Velden, T., Rieger, O., Kot, B., & Sengers, P. (2008, April). In-car gps navigation: engagement with and disengagement from the environment. In Proceedings of the SIGCHI Conference on Human Factors in Computing Systems (pp. 1675-1684). ACM.‏ http://leshed.comm.cornell.edu/pubs/chi1103-leshed.pdf

Wolbers, T., & Hegarty, M. (2010). What determines our navigational abilities? Trends in cognitive sciences, 14(3), 138-146.‏

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.297.8605&rep=rep1&type=pdf

Nonverbal learning disability – is it possible to define it in terms of CHC theory? Part one.

The interesting idea to write about this subject is Meir Buchner's.

A search for papers referring directly to this subject did not yield results, so I'll try to make my own conjectures.  Due to this post's length I divided it into two parts.

In this part we'll look at the symptoms of nonverbal learning disability (NVLD).

The definition of NVLD is in dispute.

Mammarella &  Cornoldi  reviewd 35 NVLD studies and derived five diagnostic criteria.  They stress that the criteria are preliminary, since NVLD was defined differently in each study.  There is a need for more research done with a consensual definition.

Here is Mammarella &  Cornoldi's paper:

Irene C. Mammarella & Cesare Cornoldi (2014) An analysis of the criteria

used to diagnose children with Nonverbal Learning Disability (NLD), Child Neuropsychology: A Journal on Normal and Abnormal Development in Childhood and Adolescence, 20:3, 255-280,   http://dx.doi.org/10.1080/09297049.2013.796920

Of these five criteria, the authors find the first criterion necessary.  At least two of the criteria 2-4 are required, and the fifth criterion is possible.

1. Low visuospatial ability with relatively good verbal ability.  A significant discrepancy between measures of verbal ability (in CHC terms, comprehension knowledge) and measures of perceptual or visuospatial ability (in CHC terms, visuospatial processing).  The authors suggest that the discrepancy should be at least one standard deviation.  A child does not meet this criterion if his verbal ability is significantly higher than average (say, above 115) and his visuospatial ability is average.  A child does not meet this criterion if his verbal ability is significantly lower than average (say, below 85) and his visuospatial ability is two or more standard deviations below average. 
2. Visuoconstructive and fine motor  impairments.  This ability is usually measured by reproduction of geometric figures.  We don't only look at the individual's aptitude for copying a figure, but how well planned and organized that figure is.  This ability is usually measured by tests like the BEERY and RCFT.   Performance is poor if it's one or more standard deviation below average.  The authors recommend using more than one test.  With two tests performance is poor if one of the test's scores is one and a half standard deviation or more below average. 
3. Poor math achievement at school along with relatively good reading decoding ability.   NLD children do not usually have trouble recalling arithmetical facts, but they make visuospatial errors in written calculations (i.e., confusing columns, carrying/borrowing errors) and write mirrored numbers.   Not all studies find poor performance in standardized mathematics tests.  The authors recommend basing the diagnosis on a discrepancy of at least one standard deviation between intact reading decoding and poor mathematics achievement.  They recommend looking for qualitative signs of math difficulties resulting from visuospatial difficulties. 
4. Poor spatial working memory.  The problem is, that I'm not sure the authors are distinguishing  between  spatial working memory and  spatial memory.  When writing about this criterion they sometimes write " spatial working memory" and sometimes "spatial memory".  Tests measuring  spatial working memory present the child with a series of spatial stimuli, on which he has to perform mental manipulations and respond immediately.  Tests measuring spatial memory present the child with spatial stimuli and measure his ability to retrieve them after a period of time (after four minutes or more), with no manipulation.  When I looked at the tests that were used in the studies measuring  spatial working memory, usually I couldn't tell what they were, because they are described vaguely as "spatial working memory tests" or "visuospatial organization problems".  Anyway, the authors recommend that the score on a test measuring spatial working memory should be lower than average by one standard deviation or more (when using one test) and one and a half standard deviation or more in one of two tests used
5. Social and emotional difficulties.   The authors list this as another criterion for identifying a subgroup of children with NVLD.  Difficulties understanding emotions and difficulties with social skills  should  be present at school and at home and should be assessed by a clinical interview and observation.  The authors suggest using questionnaires and clinical interviews with parents and teachers.

All of the above is from Mammarella &  Cornoldi's study.

Flanagan and her colleagues, in a paper about the WISC4 test,

Flanagan, D. P., Alfonso, V. C., Mascolo, J. T., & Hale, J. B. (2011). The Wechsler Intelligence Scale for Children–Fourth Edition in Neuropsychological Practice.‏

http://static1.squarespace.com/static/53f6762ae4b02e1724aa7c77/t/542e1ed1e4b0e285694d4a47/1412308689824/Flanagan_et_al_in_Davis_Handbook.pdf

write that children with NVLD have poor math performance and poor performance in the PRI (perceptual reasoning index) and the PSI (processing speed index).  The PRI consists of the tests matrix reasoning, Block Design and Picture Concepts.  The matrix reasoning test measures fluid ability (using visual stimuli).  It's possible that processing speed is poor because the tests measuring processing speed also use visual stimuli.

Flanagan  adds, that children with NVLD performed well on forward digit span and had poor performance on backward digit span.

Rourke suggested a definition for NVLD in 1995,  that was accepted by many researchers.  According to this definition, children with NVLD have high verbal ability, good verbal rote memory, phonological awareness, verbal fluency and good verbal classification ability.  These children have weak visuospatial skills, perceptual and motor skills and nonverbal problem solving skills.  They have difficulties with math but intact word reading skills.  Often they have social difficulties resulting from visuospatial difficulties, that affect their ability to read social and visual cues like gestures and facial expressions.   This definition is from this study:

Larsen, J. M. (2011). The impact of visual memory deficits on academic achievement in children and adolescents (Doctoral dissertation, The University of Utah).‏  http://content.lib.utah.edu/utils/getfile/collection/etd3/id/461/filename/589.pdf

To all this I'll add from personal experience, that children with NVLD sometimes have reading comprehension difficulties (understanding latent and implicit meanings in texts and content related to social and cultural norms), analyzing and synthesizing a whole into parts and parts into a whole  (not only with visual stimuli, but generally paying a lot of attention to details and having difficulty seeing the gestalt), handwriting difficulties, poor drawing and written expression, and trouble understanding intonation.

Is it possible to define NVLD in terms of CHC theory?  In the next post.

Is the linkage between number and space congenital?

Mapping of numbers onto space plays a fundamental role for many aspects of mathematics, including geometry, Cartesian coordinates and mapping real and complex numbers onto lines or planes.   Children’s conceptions of how numbers map onto space shifts radically during the early school years.  Kindergarten children can represent numbers in space in a non-random manner, but their representation is compressed, seemingly logarithmic (placing, for example, the number 10 near the midpoint of a 1–100 scale). A logarithmic scale is based on orders of magnitude, rather than a standard linear scale, so each mark on the scale is the previous mark multiplied by a value.  The Richter magnitude scale is an example of a logarithmic scale.  The compressive non-linearity becomes progressively more linear over the first 3 or 4 years of schooling.

Strong support for this idea comes from a recent study of the Mundurucu, an Amazonian indigenous group with a limited number lexicon and little or no formal training:  both adults and children of this tribe map numbers and numerical quantities onto space in a logarithmic fashion.  This points to both genetic and cultural roots to numerical mapping: the ability to represent numbers in space appears to be innate, but formal mathematical training is required to refine the representation from logarithmic to linear. 

Interestingly, dyscalculic children from developed societies also show a more logarithmic representation of the numberline than controls.

Does attention affect the ability to map numbers onto a numberline in a linear fashion?  Attention has been shown to play an important role in number perception. Attentional-training (through videogame playing) increases the subitizing range (subitizing is the ability to grasp small numerosities without counting).

In this research:

Anobile, G., Cicchini, G. M., & Burr, D. C. (2012). Linear mapping of numbers onto space requires attention. Cognition, 122(3), 454-459.‏  http://win.pisavisionlab.org/PDF_Publications_PisaVisionlab/Giovanni_Anobile_Publications/2012_Linear_mapping_of_numbers_onto_space.pdf

there were only four participants:  the author and three students.  The participants watched  clusters of dots that were displayed  on a computer screen for a very short time period (not allowing them to count the dots when their quantity was large). Their task was to place the dot cluster on a numberline by clicking the mouse.    There were three possible numberlines, marked at each end with a single dot to the left and 10, 30 or 100 dots to the right.  The number of dots in a cluster was between 2 to 86 (of course, the 86 cluster appeared only with a 0-100 numberline).  In some of the trials the participants concurrently performed another task that demanded attention (pressing the mouse when a certain visual pattern appeared – a dual task).

When there was no dual task, the participants placed the dot clusters on the numberline linearly.  But in the dual task condition, participants placed the dot clusters on the numberline logarithmically.    Apparently,   the native system of number representation is logarithmic, even in typical adults with normal mathematical ability, and  the linearization of this representation requires attention.

Visual processing and mathematics

I continue to search for information about the relationship between cognitive abilities and math performance.  The more we know about it, the better we'll be able to link specific math difficulties to cognitive abilities that may be causing these specific difficulties.

Here are some of the things we know thus far about the relation between visual processing and math:

·         Visual processing is significantly and consistently linked with math in "older" children ("older" children probably refers to junior high school and high school students) (Flanagan et al, 2006).

·         Precision in placing numbers on a number line predicts future math achievement.  Some see . this ability as a measure of the number sense (Geary et al, 2012).

• Poor visuospatial skill is related with dyscalculia (Furlong et al, 2014)

• Visual processing as measured by the WJ3COG is not predictive of math achievement as measured by WJ3ACH . (McGrew& Wendling,  2010) .

Here is another study examining this relationship.

Tibber, M. S., Manasseh, G. S., Clarke, R. C., Gagin, G., Swanbeck, S. N., Butterworth, B. & Dakin, S. C. (2013). Sensitivity to numerosity is not a unique visuospatial psychophysical predictor of mathematical ability. Vision research, 89, 1-9.‏

http://www.sciencedirect.com/science/article/pii/S0042698913001491

More than 300 participants aged 6-71 were recruited to an experiment in the London science museum.  They completed a questionnaire about their age, sex, general and math education level, took a math test and performed a series of visuospatial matching tasks.

Mathematical ability was assessed using a computer-based multiple-choice test adapted from the Mathematics Calculation Subtest (WJ-Rcalc) of the Woodcock–Johnson III Tests of Cognitive Abilities.  Participants were presented with a series of problems that increased in difficulty from simple addition and subtraction through to multiplication and division of fractions and negative integers . Participants were given 30 s to respond to each problem.   The test was  terminated if the participant made a certain number of errors.  

Visuospatial processing was assessed by a visual matching test.  Two patches of oriented Gabor elements were presented to the left and right of screen centre (see figure below). Participants used a mouse to adjust the patch on the right (the test) so that it matched the appearance of the patch on the left (the reference) for a given parameter (orientation, size, numerosity or density).  As far as I know, this task does not fit any of the narrow CHC visual processing abilities.

The results showed, that older participants performed significantly better on all tasks ( visuospatial and math tasks).  This finding is surprising because I would expect a decline in performance above the age of 20-30.

It was also found that men significantly outperformed women on all tasks.

No correlation was found between the ability to match density and size and math achievement.

In participants older than 18, there was a significant correlation between the ability to match orientation and quantity and math achievement.  Such a tendency was also found in children but it was not significant.  The authors think that's because the children's sample size  was too small.

The correlation found between the ability to match quantities and math achievement is not surprising at all.  The ability to match quantities is essentially a math task (reflecting number sense) that is only performed visually.  The correlation found in this study and other studies between the ability to match quantities and math achievement is similar:  between 0.2 and 0.4.   Sensitivity to numerosity is a significant and reliable predictor of math scores.

How can we explain the correlation between the ability to match orientation and math achievement?  The authors ask this question but don’t answer it in a convincing way.  They say that there probably is a common system at the base of math and visuospatial tasks, and that people whose system is more sensitive (better) will tend to study high level math.

Does the state of our cognitive abilities affect the self?

A lot of our sense of self is embedded in our autobiographical memory – the memory of our life event, our "life story".  People usually don’t remember events that happened prior to the age of 4, and remember more events from the last 5 to 10 years of their lives.  People also tend to remember more events from the period when they were between the ages of 10 to 30 than from other periods of their lives. 

 Why?

 New and unique events happen in adolescence and early adulthood, among them events that are important for our self identity.   Due to their uniqueness, these events are kept in memory better.  They are also retrieved better, since they serve as examples to similar events encountered later in life.  This phenomenon of more memories between the ages of 10 to 30 has a cognitive explanation as well:  the cognitive systems and the memory systems (like working memory and long term memory) function optimally at this period of time.  That's why storage and retrieval of memories formed at this period is better.

The cognitive explanation for the phenomenon of more memories in the age range of 10-30 is related to the basic systems approach to autobiographical memory.  This approach argues that autobiographical memory depends on other cognitive systems since it involves the senses (the memory of an event involves sights, smells, tastes, sounds and touch) as well as language and emotions.  A deficiency in one of the cognitive systems will lead, according to this approach, to a deficiency in the content of autobiographical memory.

What do we know about success in verbal and visuospatial memory tests?  Women outperform men on verbal memory tests, while males outperform women on visuospatial memory tests.  Higher educated people succeed more on verbal and visuospatial memory tests than lower educated people.  Adolescents and young adults perform better on these tests than middle aged adults, and middle aged adults outperform older adults.  Performance on visuospatial memory tests reaches a higher peak in adolescence and early adulthood and deteriorates more steeply in middle age and older adulthood than performance on verbal memory tests.

One way to measure autobiographical memory is to compare between retrieval of a personal event right after its occurrence and retrieval of the same event after a while.  This procedure is usually done with the aid of diaries.  As the time gap between the event's occurrence and its retrieval lengthens, retrieval deteriorates.  Retrieval is affected by the valence of the event, its frequency (if it's very frequent it will be difficult to distinguish it from other similar events happening before or after this event, and so it will be harder to remember this specific event), and the amount of reminiscence (how much the person recalled this event in the time period between its occurrence and the point in time when memory for the event is tested).

This research

The relation between verbal and visuospatial memory and autobiographical memory. 

Kristo, Rouw, Murre and Janssen

http://www.sciencedirect.com/science/article/pii/S1053810014001792

was performed, like many other recent studies, through the internet.  The researchers created an internet site which has various memory tests, among them verbal and visuospatial tests, as well as questionnaires about autobiographical memories.  The site is open for every person who registers and takes as many tests as he wishes, when he wishes.

617 people wrote in the internet site about a personal event that occurred in the three days prior to writing.  They wrote, according to the researcher's requests, about the essence of the event, who was involved, where and when the event took place and described one important and one unimportant detail of the event.  They also rated the event's importance and emotional importance and its frequency.  The same people also took verbal and visuospatial memory tests.  After a period of 2,7,14,30 and 45 days the researchers contacted the participants (by email) and asked them about the events that they had previously described.

People who performed better on verbal and visuospatial memory tests performed better on the autobiographical memory tests (remembered the events better) than participants of the same age group that did less well on the verbal and visuospatial memory tests.  The ability to remember the personal event was more strongly related to the scores on the verbal memory tests than to the scores on the visuospatial memory tests.  The researchers suggest that a possible reason for this is that they did not ask visuospatial questions about the personal event (not at the time of writing nor at the later time).  Focusing attention on visuospatial aspects of the event might have contributed to a stronger relation between visuospatial memory and memory of the event.

Intelligence and Cognitive Abilities Part 9: Visual Processing

Intelligence and Cognitive Abilities Part 9:  Visual Processing

Is here

This is the last presentation in the series.   The whole series appears in the right column of the blog.

I intend and hope to update these presentations from time to time.

Enjoy, and thanks for reading.