Br J Sports Med 38:108-114 doi:10.1136/bjsm.2002.003434
  • Original article

Negative neurofunctional effects of frequency, depth and environment in recreational scuba diving: the Geneva “memory dive” study

  1. D O Slosman1,
  2. S de Ribaupierre1,
  3. C Chicherio1,2,
  4. C Ludwig1,2,
  5. M-L Montandon1,
  6. M Allaoua1,
  7. L Genton1,3,
  8. C Pichard3,
  9. A Grousset4,
  10. E Mayer5,
  11. J-M Annoni5,
  12. A de Ribaupierre2
  1. 1Division of Nuclear Medicine, Geneva University Hospital, Geneva, Switzerland
  2. 2Faculty of Psychology and Educational Sciences, University of Geneva, Geneva, Switzerland
  3. 3Nutrition Unit, Geneva University Hospital, Geneva, Switzerland
  4. 4Hopital Font-Pre, Toulon, France
  5. 5Neurology Clinic, Geneva University Hospital, Geneva, Switzerland
  1. Correspondence to:
 D O Slosman
 Geneva University Hospital, Division of Nuclear Medicine, Geneva, Switzerland;
  • Accepted 28 April 2003


Objectives: To explore relationships between scuba diving activity, brain, and behaviour, and more specifically between global cerebral blood flow (CBF) or cognitive performance and total, annual, or last 6 months’ frequencies, for standard dives or dives performed below 40 m, in cold water or warm sea geographical environments.

Methods: A prospective cohort study was used to examine divers from diving clubs around Lac Léman and Geneva University Hospital. The subjects were 215 healthy recreational divers (diving with self-contained underwater breathing apparatus). Main outcome measures were: measurement of global CBF by 133Xe SPECT (single photon emission computed tomography); psychometric and neuropsychological tests to assess perceptual-motor abilities, spatial discrimination, attentional resources, executive functioning, and memory; evaluation of scuba diving activity by questionnaire focusing on number and maximum depth of dives and geographical site of the diving activity (cold water v warm water); and body composition analyses (BMI).

Results: (1) A negative influence of depth of dives on CBF and its combined effect with BMI and age was found. (2) A specific diving environment (more than 80% of dives in lakes) had a negative effect on CBF. (3) Depth and number of dives had a negative influence on cognitive performance (speed, flexibility and inhibition processing in attentional tasks). (4) A negative effect of a specific diving environment on cognitive performance (flexibility and inhibition components) was found.

Conclusions: Scuba diving may have long-term negative neurofunctional effects when performed in extreme conditions, namely cold water, with more than 100 dives per year, and maximal depth below 40 m.


  • Conflict of interest: none declared.