Intuitive Colorimetry comes to the School of Psychology

Posted on Tuesday 29th July 2014

ColorimeterSome people find certain characteristics of visual environments (e.g. bright lights, fluorescent lighting, sunlight, and striped patterns) aversive to view. In extreme cases this can be particularly debilitating. This is termed visual stress and can reflect anomalies at either the ocular and/or cortical level.

The symptoms of visual stress include the perception of visual distortions (illusory movement, shimmer, flicker, coloured halos, etc), eye strain, as well as nausea, visual discomfort, and dizziness.

Visual stress can also trigger migraine attacks and epileptic seizures in certain individuals and can vary in magnitude within individuals due to other stressors (poor sleep patterns/mood disorders/anxiety).

One theory is that visual stress reflects an increased degree of cortical hyperexcitability, where certain neurons in the visual system become over-stimulated. Importantly, many of these symptoms can be alleviated by the use of precision coloured tints in lenses which, it is argued, helps to ameliorate and spread the stimulation across a wider neuronal network.

Dr Jason Braithwaite who heads The Selective Attention and Awareness Laboratory (SAAL) was recently awarded funds to purchase a Mk III Intuitive Colorimeter unit (Cerium visual technologies) for the assessment of visual stress and visual anomalies across a variety of neurological conditions and disorders.

The device allows for precise independent manipulation of the brightness, hue, and saturation of colours to determine a precision tint for an individual that is optimal for relieving the symptoms of visual stress.

As well as being equipped with the Intuitive Colorimeter, the laboratory also houses two sets of trial tint lenses, software for the delineation of spectral colour and tints, a selection of coloured overlays, and computer-based pattern-glare experiments, for a more comprehensive assessment of visual stress and the potential benefits from tints across a variety of conditions and populations.

Current project topics, including those investigating the use of precision tinting in relation to visual anomalies associated with neurological and clinical conditions include:

  • Dyslexia
  • Migraine (with and without aura)
  • Autistic spectrum disorders
  • Meares-Irlen syndrome (visual stress)
  • Dissociative disorders
  • Cortical hyperexcitability and anomalous experiences
  • tDCS brain stimulation, cortical hyperexcitability and visual stress.
  • Depression
  • Persistent elementary visual symptoms
  • Epilepsy
  • Visual stress / cortical hyperexcitability from acquired head injury and stroke
  • Aging and visual stress
  • Visual stress and anxiety / mood disorders
  • Visual stress / Cortical hyperexcitability and sleep disorders
  • Visual stress & psychosis
  • Visual stress and visual imagery