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After more than a year of researching, reviewing and writing about artificial intelligence, I’ve been wanting to learn more about AI as a thinking and planning platform. While it’s a great tool for streamlining work, it’s also being used in more creative ways, and I’ve been curious about my own thinking style. Why do I see connections and visualizations when someone speaks?………..Continue reading….
By: Carly Quellman
Source: CNET
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Critics:
Visual imagery is the ability to create mental representations of things, people, and places that are absent from an individual’s visual field. This ability is crucial to problem-solving tasks, memory, and spatial reasoning. Neuroscientists have found that imagery and perception share a number of the same neural substrates, or areas of the brain that function similarly during both imagery and perception, such as the visual cortex and higher visual areas.
Kosslyn and colleagues (1999) showed that the early visual cortex, Area 17 and Area 18/19, is activated during visual imagery. They found that inhibition of these areas through repetitive transcranial magnetic stimulation (rTMS) resulted in impaired visual perception and imagery. Furthermore, research conducted with lesioned patients has revealed that visual imagery and visual perception have the same representational organization.
This has been concluded from patients in which impaired perception also experience visual imagery deficits at the same level of the mental representation. Behrmann and colleagues (1992) describe a patient C.K., who provided evidence challenging the view that visual imagery and visual perception rely on the same representational system. C.K. was a 33-year old man with visual object agnosia acquired after a vehicular accident.
This deficit prevented him from being able to recognize objects and copy objects fluidly. Surprisingly, his ability to draw accurate objects from memory indicated his visual imagery was intact and normal. Furthermore, C.K. successfully performed other tasks requiring visual imagery for judgment of size, shape, color, and composition. These findings conflict with previous research as they suggest there is a partial dissociation between visual imagery and visual perception.
C.K. exhibited a perceptual deficit that was not associated with a corresponding deficit in visual imagery, indicating that these two processes have systems for mental representations that may not be mediated entirely by the same neural substrates. Schlegel and colleagues (2013) conducted a functional MRI analysis of regions activated during manipulation of visual imagery. They identified 11 bilateral cortical and subcortical regions that exhibited increased activation when manipulating a visual image compared to when the visual image was just maintained.
These regions included the occipital lobe and ventral stream areas, two parietal lobe regions, the posterior parietal cortex and the precuneus lobule, and three frontal lobe regions, the frontal eye fields, dorsolateral prefrontal cortex, and the prefrontal cortex. Due to their suspected involvement in working memory and attention, the authors propose that these parietal and prefrontal regions, and occipital regions, are part of a network involved in mediating the manipulation of visual imagery.
These results suggest a top-down activation of visual areas in visual imagery. Using Dynamic Causal Modeling (DCM) to determine the connectivity of cortical networks, Ishai et al. (2010) demonstrated that activation of the network mediating visual imagery is initiated by prefrontal cortex and posterior parietal cortex activity. Generation of objects from memory resulted in initial activation of the prefrontal and the posterior parietal areas, which then activate earlier visual areas through backward connectivity.
Activation of the prefrontal cortex and posterior parietal cortex has also been found to be involved in retrieval of object representations from long-term memory, their maintenance in working memory, and attention during visual imagery. Thus, Ishai et al. suggest that the network mediating visual imagery is composed of attentional mechanisms arising from the posterior parietal cortex and the prefrontal cortex.
Vividness of visual imagery is a crucial component of an individual’s ability to perform cognitive tasks requiring imagery. Vividness of visual imagery varies not only between individuals but also within individuals. Dijkstra and colleagues (2017) found that the variation in vividness of visual imagery is dependent on the degree to which the neural substrates of visual imagery overlap with those of visual perception.
They found that overlap between imagery and perception in the entire visual cortex, the parietal precuneus lobule, the right parietal cortex, and the medial frontal cortex predicted the vividness of a mental representation. The activated regions beyond the visual areas are believed to drive the imagery-specific processes rather than the visual processes shared with perception. It has been suggested that the precuneus contributes to vividness by selecting important details for imagery.
The medial frontal cortex is suspected to be involved in the retrieval and integration of information from the parietal and visual areas during working memory and visual imagery. The right parietal cortex appears to be important in attention, visual inspection, and stabilization of mental representations. Thus, the neural substrates of visual imagery and perception overlap in areas beyond the visual cortex and the degree of this overlap in these areas correlates with the vividness of mental representations during imagery.
Some educational theorists have drawn from the idea of mental imagery in their studies of learning styles. Proponents of these theories state that people often have learning processes that emphasize visual, auditory, and kinesthetic systems of experience. According to these theorists, teaching in multiple overlapping sensory systems benefits learning, and they encourage teachers to use content and media that integrates well with the visual, auditory, and kinesthetic systems whenever possible.
Educational researchers have examined whether the experience of mental imagery affects the degree of learning. For example, imagining playing a five-finger piano exercise (mental practice) resulted in a significant improvement in performance over no mental practice—though not as significant as that produced by physical practice. The authors of the study stated that “mental practice alone seems to be sufficient to promote the modulation of neural circuits involved in the early stages of motor skill learning”.
Imagery training has been effective in a series of studies, mostly in sport where participants are taught formal skills to improve a mental image. Imagery training has also been effective with individuals with low abilities.
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