Behavioral testing of mice exposed to intermediate frequency magnetic fields indicates mild memory impairment

Area of Science:

• Environmental Health
• Neuroscience
• Toxicology

Background:

• Human exposure to intermediate frequency magnetic fields (MF) is rising due to widespread applications.
• Limited data exists on the potential health impacts of MF exposure.

Purpose of the Study:

• To investigate the behavioral and histopathological effects of 7.5 kHz MF exposure in mice.
• To assess potential cognitive impairments and underlying biological mechanisms.

Main Methods:

• Mice were exposed to 7.5 kHz MF at 12 or 120 μT for 5 weeks.
• Behavioral tests included spontaneous activity, motor coordination, anxiety, aggression, Morris swim task, and passive avoidance task.
• Hippocampal tissue was analyzed for astroglial activation, neurogenesis, and gene expression (BDNF, TNF-α).

Main Results:

• No significant effects on body weight, spontaneous activity, motor coordination, anxiety, or aggression were observed.
• Mice exposed to 120 μT showed a less steep learning curve in the Morris swim task and impaired memory in the passive avoidance task.
• Increased mRNA expression of tumor necrosis factor alpha (a proinflammatory cytokine) was noted in the 120 μT group, without changes in astroglial activation, neurogenesis, or BDNF mRNA.

Conclusions:

• 7.5 kHz MF exposure at 120 μT may induce mild learning and memory deficits in mice.
• These effects might be mediated by an inflammatory response in the hippocampus, as indicated by increased TNF-α expression.