7/30/2019 1973 - Persinger & Ossenkopp - International Journal of Biometeorology - Some Behavioral Effects of Pre- And Neo

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Int. J. Bio me teo r. 1973, vol. 17, numb er 3, pp. 217-220217

Som e Behavioral Effects o f P re - and Neo - N ata l E xposureto an ELF Rotat ing Magnet ic Fie ld

, b yM .A. Persinger and K.P . Ossenkopp

INTRODUCTIONRats that have been exposed during their prenat al development to an ELF(0.5 Hz) rotating m agne tic fiel d (RMF) with inten siti es rangi ng from < 1 to 30

gauss, have been repor ted to show dec rea sed ambulator y behav ior (Ossenkopp,1972; P ersi nge r, 1969), incr ease d defecation (Pe rsin ger, 1969), less bar pr es s-ing during a Sidman avoidance situation (Pe rs in ge r and Fos te r, 1970), andgr ea te r conditioned suppressi on (Pe rsi nge r and Pear , 1972), rel ati ve to controls.Pren ata lly RMF -exp osed rat s also showed significar~t inc rea ses in thyroid and~testicle weights (Ossenkopp, Koltek and Pe rs in ge r, 1972). To fur the r te st thebeha viora l consequenc es of prenatal RMF exposure, we decided to use otheroperant techniques. Res ear ch with the Halasz proced ure (delayed conditionedapproach) has shown that rats with various brain lesions can be differentiated insituations where other more stat ic procedures are relati vely insensit ive (e. g. ,Halasz, et al. , 1970). A modified ver sion of this pro ced ure was used in thepresent s tudies.

METHODSUBJECTS. Sixteen sixty day old femal e Holtzman strain albino rats wereused as sub jects. Eight of the animals had been exposed during the ir fetal de vel -opment to a 0.5 Hz rotat ing mag netic fie ld (RMF) with intensi tie s of eit her < 1-3gauss (RMF -L group) or 3-30 gauss (RMF-H group). The other eight subjectshad been exposed during thei r prenatal developme nt to either a control or sham -RMF field.APPARATUS. The RMF was creat ed by two hor sesh oe m agnets rotating inopposite direction about their major axes at 30 rot/rain by an electric motor.More prec ise descr iptio ns and a diagr am of the apparatus have been publishedelse wher e (Pe rsin ger and Pear, 1972).PROCEDURE. The breedi ng and exposure proce dur es for ' the mot her s of thesubjects used in this study have been desc ribe d e ar li er (Ossenkopp et al. , 1972;Per sin ger , 1969). Essentia lly, following exposur e to the RMF with irrtensities ofeit her 0.5- 3 o r 3-30 gauss during prenat al days 1 to 21 (birth), the anim als andthei r mothers were remov ed from the experimental s i tuation. Control subjectshad spent their prenata l developmen't in an are a 200 em fr om the cl ose st magnet,

*) Environment al Psychophysiology Laborato ry, Department of Psychology,Laure ntian Univ ersi ty, Sudbury, On'tario, Canada.**) Depar tmen t of Psychology, Uni ver sit y of Manitoba, Winnipeg, Manitoba,Canada.Pres ent ed at the Sixth International Biome teo rolo gica l Congress, Noordwijk,The Netherl ands, 3-9 Sept embe r 1972.

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R E S U L T S A N D D I S C U SS I O NF i g u r e 1 s u m m a r i z e s t h e r a t i o of t o t a l s e s s i o n r e s p o n s e s o v e r m e a n b a s e l i n et o t a l r e s p o n s e s f o r b a s e l i n e , s t e p ( _ g ) a n d c o n s e q u e n t d a y s . A s c a n b e s e e n , t h eR M F - e x p o s e d r ~ t s ( P l - 2 1 ) e m i t t e d s i g n i f i c a n t ly m o r e (p < 0 .0 1 ) b a r p r e s s e s t h a n

e i t h e r c o n t r o l s o r s h a m a n i m a l s w h e n t h e 1 0 s e c d e l a y w a s i n t r o d u c e d . A n e x -p o s u r e i n t e n s i t y d e p e n d e n c e w a s e v i d e n t b u t n o t s t a t i s t i c a l l y s i g n i f i c a n t .03Ldn IZ 1 . 8 0 A P ( I - 2 1 ) M - L , n= 4w o P ( I - 2 1 ) M - H , n = 4d 1.70

Ld 1.60

~ 1 .5003