Medical/biological study (experimental study)

Disturbance of the magnetic field did not affect spatial memory med./bio.

By: Li Y, Zhang C, Song T

Published in: Physiol Res 2014; 63 (3): 377-385

Aim of study (acc. to author)

To investigate the effects of previous training and exposure to extremely low frequency magnetic fields on memory and learning in rats.

Background/further details

Four groups of rats were examined (n=10 per group): 1.) Morris water maze training + sham exposure, 2.) magnetic field exposure, 3.) Morris water maze training + magnetic field exposure and 4.) sham exposure.
Training of the rats in the Morris water maze (group 1 and 3) was performed before the exposure/sham exposure period. After the 90 days of exposure/sham exposure, all groups were subjected to a 6-day training and testing in the Morris water maze.

Endpoint

cognitive/behavioral endpoints: memory and learning

Exposure

- 50/60 Hz
- magnetic field

Exposure	Parameters
Exposure 1: 50 Hz Exposure duration: continuous for 90 days	magnetic flux density: 100 µT

Exposure 1

Main characteristics

Frequency	50 Hz
Type	magnetic field
Exposure duration	continuous for 90 days

Exposure setup

Exposure source	Helmholtz coils
Chamber	cage and its equipment were made of plastic and glass, five rats per cage
Setup	diameter of coils 1.4 m, temperature differences between exposure and sham exposure were less than 0.2°C
Sham exposure	A sham exposure was conducted.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	100 µT	-	-	-	-

Exposed system:

Methods Endpoint/measurement parameters/methodology

cognitive/behavioral endpoints: memory and learning (Morris water maze)

Investigated system:

investigation on living organism

Time of investigation:

after exposure

Main outcome of study (acc. to author)

Rats that were trained previously in the Morris water maze (group 1 and 3) showed significantly better memory and learning abilities than not trained rats. However, no difference in the memory and learning ability was observed between magnetic field exposed rats and sham exposed rats.
The results indicate that exposure to extremely low frequency magnetic fields has no influence on the memory and learning ability in rats.

Study character:

medical/biological study
experimental study
full/main study
double-blind study

Study funded by

National Natural Science Foundation (NSFC), China
State Key Program of National Natural Science of China

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