It is hard for most us to imagine a world without cell phones today. Ever since the explosion in numbers of cell phone users, scientists have been concerned about the ill effects of cell phone radiation on the health of the users. The connection between cell phone usage and various types of cancer (leukemia, brain tumors, acoustic neuroma etc.) is widely known and debated. However, relatively fewer people are aware of the effect of cell phone radiation on the neurological and cognitive function.
Haarala et. al conducted behavioral tests in a case control study to conclude that normal cell phones do not affect the cognitive function of users.  Huber et. al. have proved that pulsed electromagnetic field exposure, as caused by cell phones affects regional Cerebral Blood Flow (CBF) and waking and sleep EEG.  Further they establish that exposure during waking modifies the EEG during subsequent sleep.  Thus the changes induced by EMF outlast the exposure period. Hung et. al used talk, silent and stand by modes in their study to conclude that the talk mode signal in fact delays sleep onset as determined by EEG patterns.  Hossman and Herman concluded that pulsed RF radiation from mobile phones damage brain cells that can lead to headache, mood swings, lethargy and depression.  Salford et. al. have also proved that electro magnetic radiation, such as those caused by the mobile phones can accelerate dementia and early onset of Alzheimer. 
Overall, from various studies done in this field, it is fairly clear that electro magnetic radiations from cell phones and their towers may be responsible for causing cognitive decline and damage to neuronal cells in users and nearby residents. Hence, precaution may be exercised to minimize exposure and use protection devices.
© Shubhra Jain. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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