Mobile phone exposure and spatial memory

Radiofrequency (RF) emission during mobile phone use has been suggested to impair cognitive functions, that is, working memory. This study investigated the effects of a 2 1/2 h RF exposure (884 MHz) on spatial memory and learning, using a double-blind repeated measures design. The exposure was designed to mimic that experienced during a real-life mobile phone conversation. The design maximized the exposure to the left hemisphere. The average exposure was peak spatial specific absorption rate (psSAR10g) of 1.4 W/kg. The primary outcome measure was a "virtual" spatial navigation task modeled after the commonly used and validated Morris Water Maze. The distance traveled on each trial and the amount of improvement across trials (i.e., learning) were used as dependent variables. The participants were daily mobile phone users, with and without symptoms attributed to regular mobile phone use. Results revealed a main effect of RF exposure and a significant RF exposure by group effect on distance traveled during the trials. The symptomatic group improved their performance during RF exposure while there was no such effect in the non-symptomatic group. Until this new finding is further investigated, we can only speculate about the cause.

[1]  R. de Seze,et al.  No effect on cognitive function from daily mobile phone use , 2005, Bioelectromagnetics.

[2]  N. Kuster,et al.  Electromagnetic fields, such as those from mobile phones, alter regional cerebral blood flow and sleep and waking EEG , 2002, Journal of sleep research.

[3]  A W Preece,et al.  Effect of a 915-MHz simulated mobile phone signal on cognitive function in man. , 1999, International journal of radiation biology.

[4]  Sargo Aalto,et al.  Mobile Phone Affects Cerebral Blood Flow in Humans , 2006, Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism.

[5]  Peter Achermann,et al.  Pulsed radio frequency radiation affects cognitive performance and the waking electroencephalogram , 2007, Neuroreport.

[6]  J. Barrash.  A historical review of topographical disorientation and its neuroanatomical correlates. , 1998, Journal of clinical and experimental neuropsychology.

[7]  A. Ahlbom.  Guidelines for limiting exposure to time-varying electric, magnetic, and electromagnetic fields (up to 300 GHz) , 1998 .

[8]  E. Lyskov,et al.  Psychophysiological tests and provocation of subjects with mobile phone related symptoms , 2006, Bioelectromagnetics.

[9]  Con Stough,et al.  The effect of electromagnetic fields emitted by mobile phones on human sleep , 2005, Neuroreport.

[10]  Christian P Karger,et al.  Mobile phones and health: a literature overview. , 2005, Zeitschrift fur medizinische Physik.

[11]  M. Carino,et al.  Acute exposure to a 60 Hz magnetic field affects rats' water-maze performance. , 1998, Bioelectromagnetics.

[12]  P. Achermann,et al.  Dosimetric evaluation and comparison of different RF exposure apparatuses used in human volunteer studies , 2008, Bioelectromagnetics.

[13]  Matti Laine,et al.  902 MHz mobile phone does not affect short term memory in humans , 2004, Bioelectromagnetics.

[14]  M. D’Esposito,et al.  The parahippocampus subserves topographical learning in man , 1996, NeuroImage.

[15]  Riccardo Russo,et al.  Does acute exposure to mobile phones affect human attention? , 2006, Bioelectromagnetics.

[16]  H. Lai,et al.  Acute exposure to pulsed 2450-MHz microwaves affects water-maze performance of rats. , 2000, Bioelectromagnetics.

[17]  A. Preece,et al.  Effect of 902 MHz mobile phone transmission on cognitive function in children , 2005, Bioelectromagnetics.

[18]  Matti Laine,et al.  Pulsed and continuous wave mobile phone exposure over left versus right hemisphere: Effects on human cognitive function , 2007, Bioelectromagnetics.

[19]  S. Resnick,et al.  Age differences in the neural systems supporting human allocentric spatial navigation , 2006, Neurobiology of Aging.

[20]  Niels Kuster,et al.  Guidance for exposure design of human studies addressing health risk evaluations of mobile phones , 2004, Bioelectromagnetics.

[21]  A. Postma,et al.  Gender differences in memory for objects and their locations: A study on automatic versus controlled encoding and retrieval contexts , 2008, Brain and Cognition.

[22]  Niels Kuster,et al.  The effects of 884 MHz GSM wireless communication signals on headache and other symptoms: An experimental provocation study , 2008, Bioelectromagnetics.

[23]  Matti Laine,et al.  Effects of electromagnetic field emitted by cellular phones on the EEG during an auditory memory task: A double blind replication study , 2004, Bioelectromagnetics.

[24]  S. Resnick,et al.  Effects of age on virtual environment place navigation and allocentric cognitive mapping. , 2002, Behavioral neuroscience.

[25]  Peter Achermann,et al.  Pulsed high-frequency electromagnetic field affects human sleep and sleep electroencephalogram , 1999, Neuroscience Letters.

[26]  R. Takegata,et al.  Integrated neural representation of sound and temporal features in human auditory sensory memory: an event-related potential study , 1999, Neuroscience Letters.

[27]  N. Raz,et al.  Extrahippocampal contributions to age differences in human spatial navigation. , 2007, Cerebral cortex.

[28]  Rodney J Croft,et al.  Acute mobile phone operation affects neural function in humans , 2002, Clinical Neurophysiology.

[29]  R. Morris,et al.  Place navigation impaired in rats with hippocampal lesions , 1982, Nature.

[30]  Augusto Gnisci,et al.  Gender differences in object location memory in a real three-dimensional environment , 2005, Brain and Cognition.

[31]  Richard S. J. Frackowiak,et al.  Knowing where and getting there: a human navigation network. , 1998, Science.