In this paper, the scope of the study was to investigate strange-face illusions in patients with depression. showed that some schizophrenic patients perceived much more intense strange-face apparitions than healthy individuals. These included huge deformations of one's own face (reported by 66% of individuals), a monstrous face (48%), an unknown person (28%), an archetypal face (28%), a face of a parent or relative (18%), and an animal face (18%). In a study set-up, under controlled laboratory conditions, 50 healthy young adults, after about one minute of mirror-gazing, began to perceive strange-face apparitions. Strange-face in the mirror illusions are apparitional experiences that are produced by gazing at one's own face reflected in a mirror, under low illumination. These decreases in depression may be produced by deficits of facial expression and facial recognition of emotions, which are involved in the relationship between the patient (or the patient's ego) and his face image (or the patient's bodily self) that is reflected in the mirror. Depression patients compared to healthy controls showed shorter duration of apparitions minor number of strange faces lower self-evaluation rating of apparition strength lower self-evaluation rating of provoked emotion. Apparitions of strange faces in the mirror were very reduced in depression patients compared to healthy controls. When the MGT ended, the experimenter assessed patients and controls with a specifically designed questionnaire and interviewed them, asking them to describe strange-face apparitions. The experiment was a 7-minute mirror-gazing test (MGT) under low illumination. In this research, patients with depression were compared to healthy controls with respect to strange-face apparitions. Observers see distortions of their own faces, but they often see hallucinations like monsters, archetypical faces, faces of relatives and deceased, and animals. "A tiger is a tiger on the right side and the left side, but a word read in the mirror loses its meaning - although now we know that it is not as incomprehensible for our visual system as we thought, because it is capable of processing it as if it were correct," the researcher concludes.In normal observers, gazing at one's own face in the mirror for a few minutes, at a low illumination level, produces the apparition of strange faces. The scientific community has yet to discover how reading, a skill that is learnt relatively late in human development, can inhibit mental rotation in a mirror, a visual capacity that is common to many animals. "Now we know that rotating letters is not a problem that is exclusive to some dyslexics, since everybody often does this in a natural and unconscious way, but what we need to understand is why people who can read normally can inhibit this, while others with difficulties in reading and writing cannot, confusing 'b' for 'd', for example," explains Duñabeitia. The researcher gives reassurance to parents who worry when their children reverse their letters when they start to write: "This is the direct result of the mirror rotation property of the visual system." In fact, it is common for children to start to write this way until they learn the "established" forms at school. "These results open a new avenue for studying the effects of involuntary rotation of letters and words in individuals with reading difficulties (dyslexia) and writing problems (dysgrafia)," Duñabeitia explains. The results of the encephalogram showed in both cases that, at between 150 and 250 milliseconds, the brain's response upon seeing the words as reflected in the mirror was the same as when they are read normally. In the first, the participants were shown words with some of the letters and other information rotated for 50 milliseconds (an imperceptible flash, which is processed by the brain) while in the second case the entire word in the mirror was rotated (for example HTUOM INSTEAD OF MOUTH). In order to carry out this study, which has been published in the journal NeuroImage, the researchers used electrodes to monitor the brain activity of 27 participants while carrying out two experiments in front of a computer screen. "At a very early processing stage, between 150 and 250 milliseconds, the visual system completely rotates the words reflected in the mirror and recognises them," says Jon Andoni Duñabeitia, lead author of the study, "although the brain then immediately detects that this is not the correct order and 'remembers' that it should not process them in this way." Most people can read texts reflected in a mirror slowly and with some effort, but a team of scientists from the Basque Centre on Cognition, Brain and Language (BCBL) has shown for the first time that we can mentally turn these images around and understand them automatically and unconsciously, at least for a few instants.
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