Effects of modafinil and methylphenidate on visual attention capacity: a TVA-based study

Psychopharmacology (Berl). 2010 Jun;210(3):317-29. doi: 10.1007/s00213-010-1823-x. Epub 2010 Mar 30.


Introduction: Theory of visual attention (TVA; Bundesen 1990) whole report tasks allow the independent measurement of visual perceptual processing speed and visual short-term memory (vSTM) storage capacity, unconfounded by motor speed. This study investigates how cognitive enhancing effects of psychostimulants depend on baseline performance and individual plasma levels.

Materials and methods: Eighteen healthy volunteers (aged 20-35 years) received single oral doses of either 40 mg methylphenidate, 400 mg modafinil or placebo in a counterbalanced, double-blind crossover design. A whole report of visually presented letter arrays was performed 2.5-3.5 h after drug administration, and blood samples for plasma level analysis were taken.

Results: Methylphenidate and modafinil both enhanced perceptual processing speed in participants with low baseline (placebo) performance. These improvements correlated with subjective alertness. Furthermore, we observed differential plasma level-dependent effects of methylphenidate in lower and higher performing participants: higher plasma levels led to a greater improvement in low-performing participants and to decreasing improvement in high-performing participants. Modafinil enhanced visual short-term memory storage capacity in low-performing participants.

Conclusions: This is the first pharmacological investigation demonstrating the usefulness of a TVA task for high-resolution and repeated cognitive parameter estimation after cognitive-enhancing medication. Our results confirm previous findings of attentional capacity improvements in low performers and extend the baseline dependency model to methylphenidate. Plasma level-dependent effects of psychostimulants can be modelled on an inverted U-shaped dose-response relationship, which is highly relevant to predict cognitive enhancing and detrimental effects of psychostimulants in patients with cognitive deficits (e.g., attention deficit hyperactivity disorder) and healthy volunteers (e.g., self-medicating academics).

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Attention / drug effects*
  • Attention / physiology
  • Benzhydryl Compounds / pharmacology*
  • Cross-Over Studies
  • Double-Blind Method
  • Female
  • Humans
  • Male
  • Methylphenidate / pharmacology*
  • Modafinil
  • Photic Stimulation / methods
  • Psychomotor Performance / drug effects*
  • Psychomotor Performance / physiology
  • Reaction Time / drug effects
  • Reaction Time / physiology
  • Visual Perception / drug effects*
  • Visual Perception / physiology
  • Young Adult


  • Benzhydryl Compounds
  • Methylphenidate
  • Modafinil