Hundreds of times during a baseball game, the home plate umpire must instantaneously categorize a fast-moving pitch as a ball or a strike. In new research from the University of Chicago, scientists have pinpointed an area in the brain where these kinds of visual categories are encoded.
While monkeys played a computer game in which they had to quickly determine the category of a moving visual stimulus, neural recordings revealed brain activity that encoded those categories. Surprisingly, a region of the brain known as the posterior parietal cortex demonstrated faster and stronger category-specific signals than the prefrontal cortex, an area that is typically associated with higher level cognitive functions.
"This is as close as we've come to the source of these abstract signals" said David Freedman, PhD, assistant professor of neurobiology at the University of Chicago. "One of the main points this study suggests is that the parietal cortex is more involved in the categorization process than we had expected."
Organizing the chaos of the surrounding world into categories is one of the brain's key functions. For instance, the brain can almost immediately classify a broad range of four-wheeled vehicles into the general category of "car," allowing a person to quickly take the appropriate action. Neuroscientists such as Freedman and his laboratory team are searching for the brain areas responsible for storing and assigning these categories.
"The number of decisions we make per minute is remarkable," Freedman said. "Understanding that process from a basic physiological perspective is bound to lead to ways to improve the process and to help people make better decisions. This is particularly important for patients suffering from neurological illnesses, brain injuries or mental illness that affect decision making."
Ten years ago, experiments by Freedman and his colleagues found neurons were encoding category signals in the prefrontal cortex (PFC), a region thought to control important mental tasks such as decision making, rule learning and short-term memory. But in subsequent experiments, Freedman found a region of the parietal cortex called the lateral intraparietal area (LIP), thought to be primarily involved in basic visual and spatial processing, also encoded category information.
For the new study, to be published in the journal Nature Neuroscience, Freedman and graduate student Sruthi Swaminathan conducted the first direct comparison of prefrontal cortex and parietal cortex during categorization tasks. Monkeys were taught a simple game in which they classified dots moving in different directions into one of two categories. The subjects were shown two sets of moving dots one second apart, then held or released a joystick based on whether the two stimuli belonged to the same category or different categories.
During the task, scientists recorded neural activity in PFC and LIP. Neurons in both areas changed their activity according to the learned categories; for example, increasing firing for one category and decreasing for the other. However, category-specific neurons in LIP exhibited stronger and faster (by about 70 milliseconds) changes in activity during the task than those recorded from PFC.
"The relative timing of signals in the two brain areas gives us an important clue about their roles in solving the categorization task. Since category information appeared earlier in parietal cortex than prefrontal cortex, it suggests that parietal cortex might be more involved in the visual categorization process, at least during this task," Freedman said.
More evidence for the primacy of parietal cortex was provided by an experiment where scientists threw their subjects a curveball. The monkeys were shown an ambiguous set of moving dots on the border between the two learned categories, then asked to compare them with a second set of non-ambiguous dots — a test with no correct answer. The subjects were required to make a decision about which category the ambiguous stimuli belonged to, and once again LIP neurons corresponded to that decision more closely than PFC.
"During the decision process, parietal cortex activity is not just correlated — it even predicts ahead of time what the monkey will tell you," Swaminathan said. "You can record neuronal activity in parietal cortex and, in many cases, predict with great reliability what the monkey will report."
In humans, the ambiguous stimuli would be similar to an umpire deciding whether a borderline pitch was a ball or a strike — a highly specialized real world example of the visual motion categorization task used in these experiments, Freedman said.
"In a lot of ways, that's the process we hope to understand, this umpire calling balls and strikes," he said. "It's an interesting learned behavior that's highly critical for an individual to perform with great reliability, and it's a spatial categorization with a sharp boundary, so we think it's the same process."
Next, Freedman's laboratory hopes to look at how the brain changes during the category-learning process, examining whether the category signals first arise in the parietal cortex or start in the prefrontal cortex before transferring to visual regions of the brain. The results may help scientists reverse engineer some of the brain's most important tasks in daily life.
"Making effective decisions and evaluating every situation that you're in moment by moment is critical for successful behavior," Freedman said. "We're really interested in what changes occur in the brain to allow you to recognize not just the features of a stimulus, but what it is and what it means."
More information: Nature Neuroscience Jan. 15 doi: 10.1038/nn.3016
Provided by University of Chicago Medical Center
"Neural balls and strikes: Where categories live in the brain." January 15th, 2012. http://medicalxpress.com/news/2012-01-neural-balls-categories-brain.html
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Robert Karl Stonjek
Robert Karl Stonjek
“When the muni looked at Rama with His brothers, his eyes welled up with tears, his body became thrilled with excitement, and his mind became so enchanted by the beauty.” (Janaki Mangala, 18)
What are some of the emotions that a beautiful object elicits? Excitement is surely one of them. “Look at what I’m seeing. I can’t take my eyes off of this. I don’t want to ever not be able to see this again.” In modern times a person’s excitement over an image can be seen through their buying of a painting or storing of a photograph on their computer or handheld electronic device. Along with excitement, there could be the enchantment of the mind. In Sanskrit mohana can refer to the ability to enchant someone through attractiveness, and the more enchanting the object is, the greater their beauty. The ability to captivate the mind belongs only to those truly special works of art.
Another kind of muni is a devoted soul, a high thinker who has wisely chosen in favor of bhakti-yoga, or
The holy name is the embodiment of the supreme person it represents. Through love for the holy name, love for Godhead takes place automatically. Vishvamitra’s high standing in bhakti was shown by the reaction he had upon seeing Rama and His brothers. Tears welled up in his eyes, a thrill of excitement went through his body, and his mind became enchanted by Rama’s beauty. In the Vedas, the god of love, Kama, who is the equivalent of a cupid, is known as Madana. The Supreme Lord is so beautiful that He is known as Madana-mohana, or the enchanter of cupid. God’s spiritual form attracts even the liberated souls, captivating their minds and directing them towards transcendental love.
The incident of Vishvamitra’s visit shows us what influence Rama has on people who have a pure heart. The aim of religious practice is to remove the distractions and intoxicating influence of material nature so that the sweet vision of the Supreme Lord can be relished. If we watch a movie while distracted in mind, will we enjoy the most important aspects? Can we concentrate on a conversation with our friends if our mind is distracted? Can we study for an important exam if we are intoxicated?
“Of all that is material and all that is spiritual in this world, know for certain that I am both its origin and dissolution.” (Lord Krishna, Bhagavad-gita, 7.6)
The spiritualist inclined to worship the Supreme Lord in His personal form through regularly 
Shri Krishna, the speaker of the Gita, then explained the right course of action in a series of different ways, which were meant to apply to the different faiths that people adopt. Depending on the modes of material nature encasing the spirit soul at the time of birth, the living being adopts a certain kind of faith. Does this mean that the animals also have faith? What about the human beings such as children that don’t know anything? The default condition is ignorance, wherein one doesn’t even know the proper way to get their desired aim. As you steadily ascend the chain of knowledge, not only do the activities become purer, but so do the objectives.
In the mode of ignorance one doesn’t even know how to get the happiness they are looking for. Think of being amazed at a blazing fire and trying to touch it. Nothing good will come from the contact, either in the present or in the future; hence the act is part of ignorance. Oversleeping and excessive 
How can we leave everything to Krishna, especially if we are not inclined towards spiritual life? The holy name is Krishna’s most potent incarnation in the modern age. Just sacrifice a little time each day to chant this name, taking it as the most important regulative practice, the one thing that shouldn’t be missed in the daily routine. From connecting with Krishna, one doesn’t even need to explicitly ascend the chain of knowledge. Bhakti-yoga is in pure goodness, so not only are the activities pure, but so is the ultimate objective, that of remaining in yoga, or pure connection with God. What reward can be better than this? Just as each new day brings a renewed vigor to glorify Krishna and remember Him, the future life for the spirit soul maintains the divine connection and enthusiasm for spiritual life. The life as we know it now is simply a demarcation of time, sort of like a splice from a timeline marked off by a start and stop point. The timeline continues regardless of our viewpoint. Whether we splice or not, the soul will continue to exist. In this sense life carries on after the present body perishes. Though the body goes away, that inherent link to Krishna does not for the surrendered soul fully immersed in bhakti.