Thursday, 11 February 2021
Revisiting an optical illusion in terms of predictive processing
I recently came across a little experiment that I posted years ago on this website to show how the blind spot in each of your eyes works. The blind spot is a part of the retina where there are no photoreceptors, because it is where the axons of the retina’s ganglion cells converge and exit the eye, forming the optical nerve. As a result, there’s a corresponding area in your field of vision that doesn’t register on the retina. Hence, in theory, you shouldn’t see anything there. But in reality, you don’t see any such blank spot in your field of vision.
To find out why not, let’s revisit this optical illusion from the standpoint of predictive-processing theory, which has become more and more accepted in cognitive science over the past 10 years or so. (more…)
The Senses | Comments Closed
Thursday, 14 January 2021
Being rich makes you less empathetic (even when it’s just Monopoly money)
Today I’m going to talk about the work of social psychologist Paul Piff, whose research interests revolve around social hierarchies, economic inequality, altruism and co-operation. I learned about Piff while working on a French-language documentary inspired by the book Capital in the 21st Century, by French economist Thomas Piketty. In this documentary, Piff explains an experiment in which people playing the board game Monopoly showed disturbing changes in behaviour when they won repeatedly because the researchers had rigged the rules in their favour (more money to begin with, more dice to roll to pass Go more often, etc.)—in other words, had given them more power. I have touched on this same subject in an earlier blog post, about Dacher Keltner’s research on how wealth alienates the wealthy from their humanity. And it turns out to be no accident that these two authors’ findings are so consistent: as I just discovered this morning, they have published many articles together! (more…)
Emotions and the Brain | Comments Closed
Monday, 14 December 2020
Using science to create art.
Some scientists use science to create art. One good example is Greg Dunn, a neurobiologist and visual artist. They are a startling combination of the precise images captured by neuron-imaging technology and the traditional techniques of Japanese ink-wash painting, also known as sumi-e.
More recently, I have discovered the impressive image of David Goodsell, who transforms deadly viruses into stunning works of art. Goodsell is a biologist who studies the molecular structure of cells at Scripps Research in San Diego, California. The watercolours that he paints with such precision represent the molecules that compose human cells and the bacteria and viruses that attack them constantly (such as the HIV, Ebola and Zika viruses below, as well as coronaviruses). (more…)
From the Simple to the Complex | Comments Closed
Friday, 13 November 2020
Serious problems in the reproducibility of brain imaging results
As I’ve pointed out in previous posts, the results produced by brain-imaging technologies such as fMRI are subject to at least two limitations. First. they detect neural activation only indirectly, by monitoring blood flows in the brain. Second, the methods used to analyze such images are subject to many forms of bias. These limitations were confirmed in a troubling study by Tom Schonberg, Thomas Nichols and Russell Poldrack, entitled “Variability in the analysis of a single neuroimaging data set by many teams ”, published in the May 20, 2020 issue of the journal Nature. (more…)
From the Simple to the Complex, From Thought to Language | Comments Closed
Tuesday, 13 October 2020
Our perceptions are shaped by the possibility of imminent actions
Affordances are a key concept in cognitive science, first advanced by J.J. Gibson in 1966. As I explained in an earlier post in this blog, an affordance is an opportunity that an object offers to take action. A hammer, for example, offers the opportunity to be grasped by its handle, and a chair offers the opportunity to sit down. What is interesting about this concept of affordances is that the opportunity for action does not depend on an object’s characteristics in any absolute sense, but instead is relative: it depends on the possible relationships that a particular organism may establish with that object. A tree, for example, offers different affordances to humans, who may use it as shelter from the rain, or crows, which may use it as a perch, or to woodpeckers, which may use it as a place to hunt for food. Moreover, as the above illustration suggests, any given object (again, such as a tree), may inspire different affordances for a given organism (such as a human) depending on that organism’s motivations and/or the broader general situation. (more…)
Body Movement and the Brain | Comments Closed
