What is cognition?

People often talk about “cognition” as if it means “conscious thinking”. But that’s not how the term is used in cognitive psychology. Here’s a little collection of quotations by folk attempting to define the concept:

1. Williamson (2006):

“Cognition is usually defined as something like the process of acquiring, retaining and applying knowledge. To a first approximation, therefore, cognitive science is the science of knowing. Knowing is a relation between the knower and the known. Typically, although not always, what is known involves the environment external to the knower. Thus knowing typically involves a relation between the agent and the external environment. It is not internal to the agent, for the internal may be the same whether or not it is related to the external in a way that constitutes knowing.”

2. LeDoux (1995)

“If cognition is defined broadly to include sensory information processing, such as that occurring in the sensory thalamus and/or sensory cortex, as well as the processing that occurs in complex association areas of cortex in the frontal lobes or hippocampus, then emotional processing by the amygdala is highly dependent on cognitive processing. If cognitive processing is defined narrowly to include only the higher mental functions most likely mediated by complex association cortex, then emotion is not necessarily dependent on prior cognitive processing.”

3. Clark and Grush (1999):

“Is not the notion of a truly cognitive agent, at root, the notion of something like a reflective agent? What is needed, we believe, is just a principled way to make this idea (of a reflective agent) precise and to purge it of its original (but probably superficial) associations with episodes of conscious reflection. […] Cognizers, on our account, must display the capacity for environmentally decoupled thought and the contemplation of options. The cognizer is thus the being who can think or reason about its world without directly engaging those aspects of the world that its thoughts concern.”

4. Neisser (1967):

“… the term “cognition” refers to all processes by which the sensory input is transformed, reduced, elaborated, stored, recovered, and used. It is concerned with these processes even when they operate in the absence of relevant stimulation, as in images and hallucinations… Given such a sweeping definition, it is apparent that cognition is involved in everything a human being might possibly do; that every psychological phenomenon is a cognitive phenomenon. But although cognitive psychology is concerned with all human activity rather than some fraction of it, the concern is from a particular point of view. Other viewpoints are equally legitimate and necessary.”


Clark, A., & Grush, R. (1999). Towards a cognitive robotics. Adaptive Behavior, 7 (1), 5-16.

LeDoux, J. E. (1995). Emotion: Clues from the brain. Annual Reviews of Psychology, 46, 209-235.

Neisser, U. (1967). Cognitive psychology. Meredith Publishing Company.

Williamson, T. (2006). Can cognition be factorized into internal and external components? In R. J. Stainton (Ed.), Contemporary debates in cognitive science. Malden MA: Blackwell Publishing.


This is brilliant (thanks to the BPS Research Digest).

Lord Falconer hit the nail on the head:

“Why are we talking about the precise detail of Gordon’s personality traits… why aren’t we talking about the substance of the issues?”

“Forget all this… sort of psycho-babble from… the Penguin guide to… And LET’S LOOK AT THE REAL ISSUES!”

“You’re a most irresponsible programme for doing all of this.”

“You don’t need a man who’s a psycho-neuron-babblist to come and say is he connecting… for goodness sake.”

Some advice on factor analysis from the 60s

“What are the alternatives to factor (or component) analysis if one has a correlation whose analysis one cannot escape? There is only one alternative method of analysing a correlation matrix which needs to be mentioned, and that is to LOOK AT IT.”

“Quite the best alternative to factor analysis is to avoid being saddled with the analysis of a correlation matrix in the first place. (Just to collect a lot of people, to measure them all on a lot of variables, and then to compute a correlation matrix is, after all, not a very advanced way of investigating anything.)”

From Andrew S. C. Ehrenberg (1962). Some Questions About Factor Analysis. The Statistician, 12(3), 191-208

13 ways to look at (Galton-Pearson) correlation

Found this paper on having a nosy around to see different ways of correlating non-Gaussian variables: Joseph Lee Rodgers and W. Alan Nicewander (1988). Thirteen Ways to Look at the Correlation Coefficient. The American Statistician, 42(1), 59-66.

Therein you’ll find details of the history (apparently Gauss got there first, but didn’t care about the special case of bivariate correlation); a range of examples of how to get the coefficient (e.g., standardised covariance, standardised regression slope, a geometric interpretation in “person space”, the balloon rule). Also a nice reminder that, in terms of the maths, the dichotomy between experimental and observational analysis is false: the difference lies in interpretation. Still many people seem to think that ANOVA is for experiments and regression is for observational studies (or that SEM magically deals with causation in observational studies).

All amusing stuff.

Gender differences in psychology

My take on this:

  1. There are gender differences in ability, but not many, and the effect size is typically small* (Hyde 2005).
  2. Brain structure development is affected by a range of factors, environmental and genetic. For instance brain structure changes as a result of learning (e.g., Maguire et al, 2000). (And the phrase “hard-wired” is annoying.)
  3. A mean difference between groups, mean(group 1) > mean(group 2), on some measure does not imply that everyone in group 1 is better than everyone in group 2. So when selecting someone for a job, say, you could (a) grab a load of people with the gender which, on average, has (very slightly—see point 1) more of the ability you want and choose someone at random, or (b) you could choose someone who has more of the ability you want, and not focus on what gender they happen to be.
  4. The designers of IQ tests hack their tests to remove gender differences, for instance the designers of the British Ability Scales (version 2) “used three strategies to test for fairness and to remove items likely to increase bias” (Hill, 2005). Blinkhorn (2005) says: “Where there are sex differences to be found, detailed study of the internal workings of the test tends to show why. That’s not based on instinct, but on my professional experience in designing gender-fair tests.”


Blinkhorn, S. (2005). Intelligence: a gender bender. Nature, 438, 31-32.

Hill, V. (2005). Through the Past Darkly: A Review of the British Ability Scales. Second Edition. Child and Adolescent Mental Health, 10, 87-98.

Hyde, J. S. (2005). The gender similarities hypothesis. American Psychologist, 60, 581-592.

Maguire, E. A.; Gadian, D. G.; Johnsrude, I. S.; Good, C. D.; Ashburner, J.; Frackowiak, R. S. & Frith, C. D. (2000). Navigation-related structural change in the hippocampi of taxi drivers. Proceedings of the National Academy of Sciences of the United States of America, 97, 4398-4403

* Cis women are better at giving birth than cis men, with a large effect size.

A couple of properties of correlation

Spotted these in Langford, E.; Schwertman, N. & Owens, M. (2001) [Is the Property of Being Positively Correlated Transitive? The American Statistician, 55, 322-325.]

1. Let U, V, and W be independent random variables. Define X = U+V, Y = V+W, and Z = WU. Then the correlation between X and Y is positive, Y and Z is positive, but the correlation between X and Z is negative.

It’s easy to see why.  X and Y are both V but with different uncorrelated noise terms. Y and Z have W in common, again with different noise terms. Now X and Z have U in common: for this pair, X is U plus some noise and Z is –U plus some noise which is uncorrelated with the noise in X.

2. If X, Y, and Z are random variables, and X and Y are correlated (call the coefficient \(r_1\)), Y and Z are correlated (\(r_2\)), and \(r_1^2 + r_2^2 > 1\), then X and Z are positively correlated.

How perception determines your world

From a lovely article by John Hull:

“Sighted people, for the most part, do not recognise themselves as sighted. What I mean is that they seldom appreciate the extent to which they live in a world which is a projection from their sighted bodies. This leads to the common mistake of thinking that one’s own world is actually the only world, and so sighted people tend to unconsciously look upon those who are not in their sighted world as being without any world, and thus to be pitied. It took me a long time to realise that blindness is actually a world, a distinctive human way of living and being.”

— John Hull (10 April 2008)

“Conscious” reasoning

Read this:

For us, however, a key difference is that only conscious reasoning can make use of working memory to hold intermediate conclusions, and accordingly reason in a recursive way (Johnson-Laird, 2006, p. 69): primitive recursion, by definition, calls for a memory of the results of intermediate computations (Hopcroft & Ulmann, 1979). [… example task omitted …] The non-recursive processes of intuition cannot make this inference, but when we deliberate about it consciously, we grasp its validity (Cherubini & Johnson-Laird, 2004). Conscious reasoning therefore has a greater computational power than unconscious reasoning, and so it can on occasion overrule our intuitions.

There’s no evidence that whatever bits of memory intuition uses cannot do recursion.  Hunting through semantic memory structures can be viewed as a recursive process and the process is not (at least always) accessible to consciousness.  Aside from this, you can impose recursion on just about any process you care to analyse, and you can often remove recursion from a process description depending on what primitives are available.  Questioning whether a process “is” or “isn’t” recursive isn’t a healthy activity.  Also the jump from “recursive” to “primitive recursive”, as if they were one and the same, is deeply confusing.  See the Stanford Encyclopaedia of Philosophy for details of other flavours of recursion.

Bucciarelli, M.; Khemlani, S. & Johnson-Laird, P. N. (2008). The psychology of moral reasoning. Judgment and Decision Making, 3, 121-139

Publish AND perish?

From Exploiting the Young by John R. Lucas:

“The fundamental activity of the university is thinking, but it is only slowly and fitfully that thinking is congealed into publicly accessible thoughts. The intense arguments in the half hour after the seminar and before hall, the afternoon spent with the graduate student, the proof of a lemma vital for a colleague’s theorem thought up over a game of chess in the Mathematical Institute, the unlikely reference vouchsafed during lab tea, the long country walk exploring a new interpretation of an old master—these are pre-eminently the activities of the young, but none register unless in the fullness of time they result in a publication. True, even in old age one seeks to continue in the ways of one’s youth, but as one concentrates on getting one piece of work finished, one has to leave intriguing by-ways unexplored, and resolutely refuse to move on yet to fresh pastures. I am more disciplined, more concentrated in my thinking now than I was when I was young, but for that very reason less wide-ranging, less sparky, less ebullient. I have gained in competence, but lost in fizz.

“Does fizz matter? I think it does. We do not need to have universities in order to encourage people to do well tasks that other people can approve and assess: what is special to universities is that they are places where people are able to think things that others had not thought of before. We damage ourselves if we pressure the young to publish what they hope will be approved-of works in order to get a living wage, we are acting contrary to our most important values if we stick with a pay scale that rewards academics less for doing what is most important than for the later residue of such activities.”

Katharine Gun

Interesting elaboration of the story over at New Statesman.

The Lords discussion around the time of the discontinuation of the case is helpful for picking up the context (over at Hansard). I found this intriguing, from Lord Wright of Richmond:

“I believe I am right in recording that following the Ponting case a counsellor was appointed to help individuals in the intelligence and security agencies—I think I am right in remembering that that included GCHQ but it may not have done—faced with crises of conscience about intelligence matters. Can the noble and learned Lord tell us whether that post still exists; whether the counsellor was used in this case; and whether Mrs Gun consulted him? If not, I suggest that the existence of a counsellor, if he is still in post, is brought to the attention of all employees in the security and intelligence agencies.”

Not sure what this counsellor does. Is the idea that you go with a crisis of conscience and they give you a dose of CBT to cure it?