LONG‐TERM EXPOSURE TO EXTREMELY LOW‐FREQUENCY MAGNETIC FIELDS IMPAIRS SPATIAL RECOGNITION MEMORY IN MICE

1 In the present study, we investigated the short‐ and long‐term effects of extremely low‐frequency (ELF) magnetic fields on spatial recognition memory in mice by using a two‐trial recognition Y‐maze that is based on the innate tendency of rodents to explore novel environments. 2 Mice were exposed to 25 or 50 Hz electromagnetic fields for either 7 (short term) or 25 days (long term) and then tested in the Y‐maze. 3 The results indicated that neither short‐ nor long‐term exposure to magnetic fields affected the locomotor activity of mice in the Y‐maze. However, long‐term exposure to 50 Hz fields reduced recognition of the novel arm. 4 Our findings suggest that ELF magnetic fields impair spatial recognition memory in the Y‐maze depending on the field strength and/or duration of exposure.

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