Posts Tagged ‘experimental psychology’

David Copperfield would love nudge

August 5, 2008

Drake Bennett writes a piece in this weekend’s Boston Globe about what magicians and neuroscientists share in common, which Cass Sunstein points out is closely related to Nudge. Bennett writes:

As magicians have long known and neuroscientists are increasingly discovering, human perception is a jury-rigged apparatus, full of gaps and easily manipulated…A great deal of the success of a piece of magic is simply getting the audience’s attention and sending it to the wrong place – to a right hand flourishing a wand while the left secrets a ball away in a pocket or plucks a card from a sleeve. Magic shows are masterpieces of misdirection: they assault us with bright colors and shiny things, with puffs of smoke and with the constant obfuscatory patter that many magicians keep up as they perform.

Neuroscientists are so interested in what magicians have practiced for years that the New York Academy of Science has asked magician Apollo Robbins to make a January presentation on vision, and other magicians will speak to brain researchers at the Society of Neuroscience annual meeting in 2009. We’re still waiting for neuroscience’s debut in Vegas.

The vanishing ball illusion is one of the most basic tricks a magician can learn: a ball is thrown repeatedly into the air and caught. Then, on the final throw, it disappears in midair. In fact, the magician has merely mimed the last throw, following the ball’s imagined upward trajectory with his eyes while keeping it hidden in his hand.

But if the technique is easily explained, the phenomenon itself is not. If done right, the trick actually makes observers see the ball rising into the air on the last toss and vanishing at its apex. As (Ronald A. Rensink, a professor of computer science and psychology at the University of British Columbia) points out, this is something more powerful than merely getting someone to look in the wrong direction – it’s a demonstration of how easy it is to nudge the brain into the realm of actual hallucination. And cognitive scientists still don’t know exactly what’s causing it to happen.

Rensink is a co-author on a paper about magic and psychology in the current issue of Trends in Cognitive Sciences. The journal is gated, but the Science news release is here. For videos of the illusions in Rensink’s paper click here.

Can’t get enough? Watch this 16 minute clip of cognitive neuroscientist Al Seckel, a master of illusions, show how confused our minds can get – even when we know what is coming.

Replicating the Solomon Asch experiment today

June 13, 2008

The Asch experiments have been replicated many times, and they keep producing the same results. (For more on conformity and deliberation, see a recent post about a new Sunstein paper.)

Choices don’t just confuse, they exhaust

May 29, 2008

When more choices are available, more decisions are required. Psychological research has previously noted how increasing choices can turn people off, leading them to opt-out of the decision making process. (For retailers, this phenomenon means lower sales and profits.)

Now a new paper in the Journal of Personality and Social Psychology claims that increasing the choice set saps people’s brainpower and energy more quickly. Researchers asked mall visitors to make choices about consumer goods, college courses, or class materials.

The scientists then asked each group to participate in one of two unpleasant tasks. Some were told to finish a healthy but ill-tasting drink (akin to taking ones medicine). Other participants were told to put their hands in ice water. The tasks were designed to test how the previous act of choosing, or not choosing, affected peoples’ ability to stay on task and maintain behaviors aimed at reaching a goal. Researchers found that the participants who earlier had made choices had more trouble staying focused and finishing the disagreeable but goal-focused tasks compared to the participants who initially did not have to make choices.

Another classic experiment from behavioral science on video

May 28, 2008

Solomon Asch’s conformity experiments in which individuals gave obviously incorrect answers – such as pointing out which of three lines was the longest – about about one-third of the time simply because other members of a group also answered incorrectly.

The decision-making moments in the Milgram experiment

April 14, 2008

If you took Psychology 101 in college you might have seen the Milgram experiment, one of the most famous in social science. A 50 minute edited video of it popped up recently on You Tube. We discuss the Milgram experiment in Nudge not to explain the rise of fascism – as has become the common view of the experiment today – but rather to make a point about how social pressures nudge people to accept conclusions that are at odd with their own views of reality, and then shape their behavior.

See the videos and continue reading the post here.

Watch the cards

April 3, 2008

Another great video. We don’t want to ruin the punch-line, but we suggest you pay attention to the cards and read the “Watch out for cyclists” post if you haven’t already.

Watch out for cyclists

March 25, 2008

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