THE SENSITIVITY OF COGNITIVE-PROCESSES TO THE INHOMOGENEITY OF NATURAL MAGNETIC-FIELDS

Three experiments were carried out to study the influence of inhomogen eity of natural magnetic field (MF) on animal cognition; Wistar rats ( n = 90) were placed in a complicated problem environment, in which the y were to form food-operant behavior under conditions of natural MF (C ond. 1) and MFs produced by iron objects (Cond. 2) or by magnets (Cond . 3). Unlike the control group (Cond. 1), all rats in Cond. 2 and 3 we re unable to form operant behavior. Weak MF caused both locomotor and emotional depression, and there was no exploratory activity shown duri ng 6 sessions. Brief external stimulation removed locomotor depression , and animals formed operant behavior similar to latent learning (Cond . 2) or ''insight'' (Cond. 3). Performance efficiency was lower while the level of stress manifestation was higher in Cond. 2 and 3 than in the control at the stage of stabilization. It has been proposed that M F reduces the activity of brain motivation centers and prevents the de velopment of complicated forms of cognitive activity.