Schizophrenia: Delusion without illusion

October 25, 2005

British scientists say schizophrenics aren't fooled by a visual illusion and can judge it more accurately than can non-schizophrenic observers.

The study by University College London and King's College London researchers suggests in everyday life, schizophrenics take less account of visual context. If this is part of a more general failure to deal appropriately with context, it could explain why some sufferers misattribute people's actions or feel persecuted.

The researchers used an illusion in which an object's contrast appears reduced by its surroundings. A medium-contrast patterned disc was shown to volunteers, who had to judge its appearance in the presence of a high-contrast background. Of 15 participants with chronic schizophrenia, 12 were found to make more accurate judgments than the most accurate person in a control group of 33 non-schizophrenic volunteers.

Dr Steven Dakin of the UCL Institute of Ophthalmology says: "We often think of people with schizophrenia as not seeing the world the way it really is -- for example, during hallucinations -- but we have shown that sometimes their vision can be more accurate than non-sufferers."

The study appears in the journal Current Biology,

Copyright 2005 by United Press International

Explore further: Interaction of tailored light with a single atom and individual nanostructures

Related Stories

Rape stats poorly reflect reality

June 22, 2015

Statistics on violence – particularly towards women and children – are highly politicised in South Africa. Typically, they serve one of two purposes: either they provide government with evidence of a good story to tell; ...

Stone tools from Jordan point to dawn of division of labor

June 12, 2015

Thousands of stone tools from the early Upper Paleolithic, unearthed from a cave in Jordan, reveal clues about how humans may have started organizing into more complex social groups by planning tasks and specializing in different ...

Herschel's hunt for filaments in the Milky Way

May 29, 2015

Observations with ESA's Herschel space observatory have revealed that our Galaxy is threaded with filamentary structures on every length scale. From nearby clouds hosting tangles of filaments a few light-years long to gigantic ...

Is it time to ditch annual performance reviews?

May 11, 2015

Most of us have had annual or semi-annual formal performance reviews, but a new paper by psychologists at Rice University reinforce the importance of continuous feedback on employee performance, and how the social environment ...

Recommended for you

How bees naturally vaccinate their babies

July 31, 2015

When it comes to vaccinating their babies, bees don't have a choice—they naturally immunize their offspring against specific diseases found in their environments. And now for the first time, scientists have discovered how ...

Image: Hubble sees a dying star's final moments

July 31, 2015

A dying star's final moments are captured in this image from the NASA/ESA Hubble Space Telescope. The death throes of this star may only last mere moments on a cosmological timescale, but this star's demise is still quite ...

Exoplanets 20/20: Looking back to the future

July 31, 2015

Geoff Marcy remembers the hair standing up on the back of his neck. Paul Butler remembers being dead tired. The two men had just made history: the first confirmation of a planet orbiting another star.

Binary star system precisely timed with pulsar's gamma-rays

July 31, 2015

Pulsars are rapidly rotating compact remnants born in the explosions of massive stars. They can be observed through their lighthouse-like beams of radio waves and gamma-rays. Scientists at the Max Planck Institute for Gravitational ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.