The effects of acute and chronic exposure of 2100 MHz radiofrequency radiation on rat mismatch negativity

Cell phones operate by emitting radiofrequency radiation (RFR), a form of electromagnetic radiation (EMR). Consequently, ongoing researches target to determine whether it poses potential risks to human health. One of these risks is related with brain and auditory system. This study aims to examine the impact of acute and chronic exposure to 2100 MHz radiofrequency radiation on mismatch negativity (MMN) in rats. In this study, we established 1-week (RFR1) and 10-week (RFR10) RFR groups from rats, which were subjected to 2100 MHz RFR exposure. Cage control groups (CC1, CC10) and sham groups (S1, S10) that were not subjected to RFR for equivalent durations were also established. Following auditory event-related potential (AERP) recordings, MMN waves were computed and analyzed. Additionally, brain samples were collected and biochemical and histological analyses were performed. The RFR1 group exhibited a reduction in AMPAR GluR2 subunit protein levels relative to the CC1 and S1 groups, although GFAP protein levels increased. Conversely, the opposite was observed in the chronic groups. Edema of astrocytic endfeet, mitochondrial damage, and lysosomal vesicles were identified in the RFR1 group. The MMN amplitude was found to be reduced in the RFR1 group relative to the CC1 group. The RFR1 group exhibited a reduction in delta and theta power relative to the S1/CC1 groups. Alpha coherence diminished in the RFR1 group relative to the S1 group, however it augmented in the RFR10 group compared to the S10 group. The assessment of event-related potentials indicated that 2100 MHz RFR led to a decrease in MMN amplitude, power spectrum, and coherence values in the RFR1 group relative to the S1 and CC1 groups, but an increase was observed in the RFR10 group compared to the S10 group. Consequently, in the acute period, 2100 MHz RFR may have adverse effects on auditory sensory memory.