Visual processing in people with and without prosopagnosia (face blindness)

School of Health Sciences

Why are people so incredibly different when it comes to their ability for recognizing others?

How specific is face processing? And how does the brain do all this?

When light falls on the eyes, they forward this message to neurons in the cerebral cortex that respond to light and shadow, orientation, color, and location. These signals are passed on to neurons with even more complex properties. Neurons have been found in the brain that seem to respond specifically to faces and have therefore been called face cells. They are mainly found in certain brain regions that seem to play an important role in identifying people visually.

Consistent with the existence of face cells and face regions, there are also examples of specific difficulties—but also specific abilities—in recognizing people by their face alone. So-called super-recognizers can even identify people they only met briefly once many years ago. At the other end of the spectrum are those who are face blind (prosopagnosic) – they are particularly poor at recognizing people by sight. The person who writes this (Heida Maria Sigurdardottir, Professor at the Department of Psychology, University of Iceland) is probably on this end of the spectrum, and has repeatedly gotten herself into trouble by introducing herself to people, only to have the person tell her that she has already met them and conversed with them many times. People with severe face blindness may even have trouble recognizing close relatives and friends based on their face alone.

Our intention

However, there is still some debate about how specific face blindness is. Surely there are face cells and face areas in the brain, but these cells and areas also respond when we look at other objects – do they then also help us recognize other objects visually? Do those who are face blind only have problems with recognizing faces, or do their problems transfer to some other objects? Or can they identify other objects using different processing methods of the brain?

In a new study conducted by the Icelandic Vision Lab (www.visionlab.is) at the Department of Psychology, University of Iceland, the intention is to record brain activity using electroencephalography (EEG) to see how the brains of face blind people react to faces and objects, and compare how the brains of people who are not face blind process the same information.

Our team

Research in the Icelandic Vision Lab focuses on all things visual, with a major emphasis on higher-level or “cognitive” aspects of visual perception. Current and/or past research has looked at several visual processes, including visual attention, eye movements, object perception, face perception, visual memory, visual statistics, and the role of experience/learning effects in perception. Some of our work concerns the basic properties of the workings of the typical adult visual system.

For information please contact: visionlab@hi.is

Principal investigator of the study:
Heiða María Sigurðardóttir, professor: heidasi@hi.is