To test whether a weak magnetic fieldpulsed over the left prefrontalbrain region at the moment of accepting or refuting a statement could increase the likelihood of later accepting a false statement as true.
Background/further details
The first stages of cognitive processing require the acceptance of all information as "true". This is followed by either accepting or rejecting this assumption. The left prefrontalbrain region is typically associated with decision making and judgement. 25 men and 25 women were assigned to 5 experimental conditions including 4 groups with specific electromagneticexposure patterns (25 Hz, 50 Hz, burst-firing, 7-10 Hz) and one sham exposure group.
Richards PM et al.
(1993):
Modification of activation and evaluation properties of narratives by weak complex magnetic field patterns that simulate limbic burst firing
cognitive/behavioral endpoints: refutation process: computer task (foreign language statements and their English equivalents were presented for 8 sec followed by 6 sec blank screen followed by a presentation of a 3 sec signal word "false" or "true" or blank screen; after the appearance of the signal word participants were stimulated for 1 sec with electromagnetic fields; at the end of the presentation of propositions, the participants were given the items again and were asked for each proposition if it was "true" or "false")
When the statements were presented again, the groups who had received the burst-firing or 25 Hzpulsedmagnetic fields during the refutation process declared about twice the number of "false" statements as "true" compared to those exposed to the 50 Hz field or sham exposure. The treatments did not significantly affect the numbers of "true" statements accepted as "false". The results suggest that magnetic fieldexposure during the refutation process of what one has been told or has heard can increase the probability that a person will accept a "false" statement as "true". Electromagnetic fields might affect physiological processes and brainelectric states that lead to a disruption of the refutation process.
Carrubba S et al.
(2008):
The effects of low-frequency environmental-strength electromagnetic fields on brain electrical activity: a critical review of the literature
Healey F et al.
(2001):
Experimental production of illusory (false) memories in reconstructions of narratives: effect size and potential mediation by right hemispheric stimulation from complex, weak magnetic fields
