Abstract. Do you know “blindsight,” when we recognize something without conscious effort? “Psychic blindness” is the opposite. Besides perfect eyesight, a person suffering from visual ‘object agnosia,’ cannot recognize an object due to the inability to associate the optical signals with the memorized concept of the object in sight. The same object could, however, be identified by the means of other senses such as hearing or touch. The article discusses some causes, examples, and even implications on self-perception of this relatively rare but interesting syndrome from a scientific point of view.
Álvarez and Masjuan (2016) state that vision is the most advanced and most important human sense. In contrast to the phenomenon of “blindsight”, i.e., when processing an object automatically without conscious effort (Rossetti, Pisella, and McIntosh, 2017), the processing of visual information can also be impaired. The impairment can be so severe that visual objects like faces and letters don’t get produced in the mind, despite perfectly working eyesight (Serino et al., 2014). Historically and by scientists from different disciplines this so called ‘visual agnosia’ was also coined as the expression of “blind in mind,” or “psychic blindness” (p. 61). Reasons for visual object agnosia can be neurodegenerative diseases as evidenced by an older patient (Bergmans, Deryck, & Bruffaerts, 2016). Damage through intoxication as reported by Bridge et al. (2013) can be a cause too, as well as a lesion through an accident as in an example from Yasuno, Hashikawa, Kabeshita, Kudo, and Kishimoto (2016).
It is hypothesized that there are two visual processes involving two different neural routes, the ventral one responsible for visual recognition and the dorsal one for the interpretation of a visual object (Álvarez & Masjuan, 2016). Visual agnosia results from an impaired ventral stream (Huberle, Rupek, Lappe, & Karnath, 2012). De-Wit, Kubilius, Op de Beeck, and Wagemans (2013) provided evidence for an automatically working visual mechanism that is responsible for interpreting parts of an object into a whole. Furthermore, a visual agnosia patient is not able to associate the visual input with an according memorized conceptualized image (Serino et al., 2014). In that case, any therapeutic association technique to bring the subconscious to awareness risks to fail. From the study of a patient who, after an infarction, could not name presented fruits and vegetables anymore, Yasuno et al. (2016) have drawn an interesting conclusion. They took the specific disablement of the ‘fruit and vegetable’ category as evidence for the existence of according categorical human neural networks that are explainable through the evolutionary importance of the recognition of fruits and vegetables for survival.
Potential impact on the self
If it can be argued that a personality is influenced by more or less unconscious drives and motivations that are shaped also based on past experiences of our social and physical (!) environment, then it may be also decisive for individual differences how one is visually processing objects. Without finally concluding, the following may provide an example for that thought experiment. For example, people suffering from body image concern (BIC) are overestimating physical flaws due to an over-emphasis on specific local visual processing, e.g., isolating a nose or a belly (Beilharz, Atkins, Duncum, & Mundy, 2016). If the local processing system worked less biased respectively in harmony with the automatic global visual processing of the whole body, a more proportionate picture of the entire physical self would be perceived (Beilharz et al., 2016). That way, a distorted visual perception (an impaired psychic sight) of one self may adversely influence one’s self-concept overall.
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