The sharp eye of a radiologist is an invaluable tool for accurate diagnosis many times. This seemingly conferred super-power is nothing but the result of visual perceptual learning. Visual Perceptual Learning (VPL) is the long-term enhancement of performance on a visual task (like spotting tumors on scans) as a consequence of repeated exposure or experience. But what actually drives this learning? In today’s super specialized world, understanding an element that brings about expertise is crucial.
Most people would agree that conscious effort to perform task by the learner is the key to VPL. Our environment is packed with features and not all this information is important to a learner. Research suggests that focused attention acts as a gate, ensuring VPL occurs in relation with the features important to the learner, this is called task relevant features.
Surprisingly, it was revealed in a study that while conscious effort is important it is not NECESSARY for VPL. The emerging view argues on the contrary, stressing on the importance of implicit processing. There are researches that exhibit the existence of task irrelevant features.
Reward on the other hand acts as a gate irrespective of task relevance. The sense of achievement after completing a task provides an internal reward, which in turn produces reinforcement signals, stimulating learning.
Hence, VPL is driven by the top-down processing of attention where task relevant features are picked upon, and task-irrelevant features are inhibited. And the bottom-up processing of reinforcement signals, wherein the task relevance of features does not matter. And these two processes are not mutually exclusive.
Like the famous quote goes “The difference between ordinary and extraordinary is that little extra”, that ‘extra’ includes alteration of various brain regions as a result of VPL. These include the regions retinotopically corresponding to the stimulus location in the primary visual cortex (V1). Besides the various hierarchical visual areas, the altering weight of connections among the decision-making regions, and higher visual cortical areas like Middle Temporal area (MT), Lateral Intra-Parietal area (LIP) are also associated with the neural changes occurring during VPL.
Now when you hear someone say “you have got a keen eye” you know exactly why and how.
References:
Sasaki, Y., Nanez, J. E., & Watanabe, T. (2010). Advances in visual perceptual learning and plasticity. Nature Reviews Neuroscience, 11(1), 53–60.
