{"id":169877,"date":"2015-05-06T17:00:53","date_gmt":"2015-05-06T21:00:53","guid":{"rendered":"http:\/\/webadmin.news-harvard.go-vip.net\/gazette\/gazette\/?p=169877"},"modified":"2019-03-08T13:33:57","modified_gmt":"2019-03-08T18:33:57","slug":"creatures-of-habit","status":"publish","type":"post","link":"https:\/\/news.harvard.edu\/gazette\/story\/2015\/05\/creatures-of-habit\/","title":{"rendered":"Creatures of habit"},"content":{"rendered":"\n\t
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Rats with lesions on their motor cortices performed tasks exactly as they had done pre-lesion. \u201cWe were very puzzled, since we all thought that these learned behaviors should require the motor cortex,\u201d said Bence \u00d6lveczky, the John L. Loeb Associate Professor of the Natural Sciences. <\/p>

Video image courtesy of Bence \u00d6lveczky<\/p><\/figcaption><\/figure>\n\n\t

\n\t\t\t\n\t\t\tHealth\t\t<\/a>\n\t\t\n\t\t

\n\t\tCreatures of habit\t<\/h1>\n\n\t\n\t\t\t<\/div>\n\t\t\n\t
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\n\t\tPeter Reuell\t<\/p>\n\t\t\t

\n\t\t\tHarvard Staff Writer\t\t<\/p>\n\t\t\t\t\t<\/address>\n\t\t<\/div>\n\n\t\t

\n\t\t\tMotor cortex is critical to learn new skills, but may not be needed to perform them, study says\t\t<\/h2>\n\t\t\n<\/header>\n\n\n\n
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When he set out to understand how the motor cortex changes with learning, Bence \u00d6lveczky, the John L. Loeb Associate Professor of the Natural Sciences, assumed, like nearly all other scientists, that unique learned motor behaviors originate in the motor cortex.<\/p>\n

What he found, however, was the opposite.<\/p>\n

To their surprise, \u00d6lveczky and his colleagues learned that while the brain\u2019s motor cortex is critically important for learning new skills, those skills, once learned, can be executed without any input from the motor cortex. The study is described in a paper published today in the journal Neuron.<\/p>\n

\u201cThe thinking has always been that the more primitive subcortical circuits are there to support innate, instinctive behaviors, while sophisticated, learned behaviors require the motor cortex,\u201d \u00d6lveczky said. \u201cOur assumption was that \u2026 when you perform a learned skill you sequence or coordinate it from the motor cortex. But in our experiments we found that even if the motor cortex was missing, there was no effect on complex learned motor sequences, so we have to conclude that subcortical circuits have the capacity to store and execute them.\u201d<\/p>\n

For many creatures, the ability to learn unique motor behaviors is a crucial adaptation. That\u2019s what allows humans to walk and talk, songbirds to sing, and predators to outsmart their prey. Virtually all of these behaviors are learned the same way, through trial and error.<\/p>\n

\u201cEssentially, you learn something by varying different aspects of your behavior and learning what works and what doesn\u2019t,\u201d \u00d6lveczky explained. \u201cWith time and much practice, the nervous system can select the actions that lead to good outcomes.\u201d<\/p>\n

As an example, \u00d6lveczky pointed to tennis players. While beginners often show large variation in their serves, the motions of experienced players are nearly identical from one serve to the next.<\/p>\n

To better understand the role that the motor cortex plays in the mastery of such skills, \u00d6lveczky and his colleagues developed a simple task that rewarded rats for pressing a lever, and then pressing it again 700 milliseconds later.<\/p>\n

Just as in any other trial-and-error learning scenario, the rats were initially rewarded for a wide range of lever presses. Over time, the contingency for success narrowed until only lever presses that were exactly 700 milliseconds apart were rewarded. Eventually, over 10,000 to 15,000 trials, each of the dozen rats in the experiment learned motor sequences equal to the task.<\/p>\n

Just as each player\u2019s serve in tennis is different, the rats solved the task in idiosyncratic ways, using precise sequences of seemingly arbitrary actions \u2014 from scratching the wall to a motion similar to a DJ spinning a record \u2014 to stick to the proper timing between lever presses.<\/p>\n\r\n\n

\nhttp:\/\/Two%20rats%20that%20have%20learned%20the%20timed%20lever-pressing%20task%20are%20seen%20performing%20it%20before%20and%20after%20lesions%20to%20the%20motor%20cortex.%20To%20the%20left%20are%20two%20examples%20taken%20before%20the%20lesion;%20on%20the%20right%20are%20two%20examples%20from%20the%20first%20day%20of%20training%20after%20the%20lesion.%20Note%20the%20stereotyped%20idiosyncratic%20behaviors%20and%20how%20they%20are%20not%20affected%20by%20motor%20cortex%20lesions.%20Videos%20are%20slowed%20down%20by%20a%20factor%20of%202.5.\u00a0%20Courtesy%20of%20Bence%20\u00d6lveczky\n<\/div>\n
Two rats that have learned the timed lever-pressing task are seen performing it before and after lesions to the motor cortex. To the left are two examples taken before the lesion; on the right are two examples from the first day of training after the lesion. Note the stereotyped idiosyncratic behaviors and how they are not affected by motor cortex lesions. Videos are slowed down by a factor of 2.5.\u00a0 Courtesy of Bence \u00d6lveczky<\/figcaption><\/figure>\n\n\r\n\n

\u201cI assume that they didn\u2019t know it was an interval timing task, but through trial and error the rats learned that if they produce a particular sequence of movements they will get a nice big drop of water,\u201d \u00d6lveczky said. \u201cAnd, importantly, once they have this figured out, the behavior is very stable and it\u2019s very hard to change because they would be changing from something that works.\u201d<\/p>\n

When \u00d6lveczky and colleagues lesioned the rats\u2019 motor cortices and returned them to the experiment, they were surprised to find that the rats were able to complete the task just as they had earlier, using exactly the same movements.<\/p>\n

\u201cWe were very puzzled, since we all thought that these learned behaviors should require the motor cortex,\u201d \u00d6lveczky said. \u201cSo we thought, what have we been missing?\u201d<\/p>\n

To find an answer, \u00d6lveczky and his colleagues began sifting through the literature on the motor cortex and discovered that the widely held assumption that learned motor skills are stored in the motor cortex was largely based on studies that had focused on fine motor skills.<\/p>\n

\u201cIf you lesion the motor cortex in those cases, performance is affected, often quite severely,\u201d \u00d6lveczky said. \u201cIn many mammals, including humans, we need the motor cortex to produce fine dexterous movements and skills.<\/p>\n

\u201cThe problem was that many people, including us, were generalizing from these studies, leaving us convinced that the motor cortex is important for all kinds of skills.\u201d he continued. \u201cBut no. It\u2019s not that the motor cortex is necessary for executing learned motor sequences, per se. It\u2019s important for dexterity, but that\u2019s a different aspect of motor skill than the one we were interested in.\u201d<\/p>\n

While the evidence suggested that the motor cortex is not necessary to perform the learned behaviors, \u00d6lveczky and his colleagues set out to test whether it was needed to learn them in the first place by lesioning rats\u2019 motor cortices before exposing them to the task.<\/p>\n

\u201cInitially, they were no different than the other rats,\u201d \u00d6lveczky said. \u201cThey pressed the lever the same, they had the same sort of movements, but lesioned rats never got there. We kept training them for many months, but their variability remained high. They never learned the task.<\/p>\n

\u201cRats that have already learned the task don\u2019t need the motor cortex,\u201d he added. \u201cBut to learn it initially, the motor cortex is absolutely necessary. It suggests that the motor cortex is a tutor that uses its superior knowledge to instruct subcortical circuits how to perform new tricks. And when these circuits get to the point where they can do the same thing every time, then the motor cortex becomes dispensable.\u201d<\/p>\n

While the study sheds new light on the role of the motor cortex in learning and performing motor skills, it also serves to highlight the previously unrecognized power of subcortical motor circuits, \u00d6lveczky said.<\/p>\n

\u201cLizards and other non-mammals are all capable of extraordinary motor feats, but none of them have a cortex,\u201d \u00d6lveczky said. \u201cOne way of thinking about this is that when mammals evolved a cortex, there was already a very impressive motor infrastructure in place, one that had been refined over millions and millions of years. But it was adapted for specific scenarios and lacked flexibility.<\/p>\n

\u201cTo increase the flexibility of the animal\u2019s behavior and allow it to learn new skills, the cortex had basically two options. It could integrate itself into what was already there, or it could reinvent everything and take full control over the animal\u2019s movements. Our results suggest that the cortex was smart and found ways to use the subcortical motor controllers to its advantage. There are now pathways in the brain that allow the motor cortex to influence and reprogram subcortical circuits to increase their utility and flexibility. Offloading the execution of stereotyped motor behaviors to these lower-level circuits frees up the motor cortex to do more sophisticated things.\u201d<\/p>\n\n\n\n<\/div>\n\n\t\t","protected":false},"excerpt":{"rendered":"

The motor cortex is critical to learn new skills, but may not be needed to perform them, a new Harvard study says.<\/p>\n","protected":false},"author":105622744,"featured_media":169922,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"gz_ga_pageviews":11,"gz_ga_lastupdated":"2020-10-18 16:22","document_color_palette":"crimson","author":"Peter Reuell","affiliation":"Harvard Staff Writer","_category_override":"","_yoast_wpseo_primary_category":"","_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[39644],"tags":[5547,21423,21424,24555,25442,27327,32557],"gazette-formats":[],"series":[],"class_list":["post-169877","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-health","tag-bence-olveczky","tag-learned-behavior","tag-learning","tag-motor-cortex","tag-neuron","tag-peter-reuell","tag-subcortical-circuits"],"yoast_head":"\nCreatures of habit — Harvard 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Loeb Associate Professor of the Natural Sciences. ","mediaId":169922,"mediaSize":"full","mediaType":"image","mediaUrl":"https:\/\/news.harvard.edu\/gazette\/wp-content\/uploads\/2015\/05\/rats605-copy.jpg","poster":"","title":"Creatures of habit","subheading":"Motor cortex is critical to learn new skills, but may not be needed to perform them, study says","centeredImage":true,"className":"is-style-full-width-text-below","mediaHeight":403,"mediaWidth":605,"backgroundFixed":false,"backgroundTone":"light","coloredBackground":false,"displayOverlay":true,"fadeInText":false,"isAmbient":false,"mediaLength":"","mediaPosition":"","posterText":"","titleAbove":false,"useUncroppedImage":false,"lock":[],"metadata":[]},"innerBlocks":[],"innerHTML":"<figure class=\"wp-block-image\"><img alt=\"\" height=\"403\" loading=\"eager\" src=\"https:\/\/news.harvard.edu\/gazette\/wp-content\/uploads\/2015\/05\/rats605-copy.jpg\" width=\"605\"\/><figcaption class=\"wp-element-caption\"><p class=\"wp-element-caption--caption\">Rats with lesions on their motor cortices performed tasks exactly as they had done pre-lesion. \u201cWe were very puzzled, since we all thought that these learned behaviors should require the motor cortex,\u201d said Bence \u00d6lveczky, the John L. Loeb Associate Professor of the Natural Sciences. <\/p><p class=\"wp-element-caption--credit\">Video image courtesy of Bence \u00d6lveczky<\/p><\/figcaption><\/figure>\n","innerContent":["<figure class=\"wp-block-image\"><img alt=\"\" height=\"403\" loading=\"eager\" src=\"https:\/\/news.harvard.edu\/gazette\/wp-content\/uploads\/2015\/05\/rats605-copy.jpg\" width=\"605\"\/><figcaption class=\"wp-element-caption\"><p class=\"wp-element-caption--caption\">Rats with lesions on their motor cortices performed tasks exactly as they had done pre-lesion. \u201cWe were very puzzled, since we all thought that these learned behaviors should require the motor cortex,\u201d said Bence \u00d6lveczky, the John L. Loeb Associate Professor of the Natural Sciences. <\/p><p class=\"wp-element-caption--credit\">Video image courtesy of Bence \u00d6lveczky<\/p><\/figcaption><\/figure>\n"],"rendered":"<header\n\tclass=\"wp-block-harvard-gazette-article-header alignfull article-header is-style-full-width-text-below centered-image\"\n\tstyle=\" \"\n>\n\t<figure class=\"wp-block-image\"><img alt=\"\" height=\"403\" loading=\"eager\" src=\"https:\/\/news.harvard.edu\/gazette\/wp-content\/uploads\/2015\/05\/rats605-copy.jpg\" width=\"605\"\/><figcaption class=\"wp-element-caption\"><p class=\"wp-element-caption--caption\">Rats with lesions on their motor cortices performed tasks exactly as they had done pre-lesion. \u201cWe were very puzzled, since we all thought that these learned behaviors should require the motor cortex,\u201d said Bence \u00d6lveczky, the John L. Loeb Associate Professor of the Natural Sciences. <\/p><p class=\"wp-element-caption--credit\">Video image courtesy of Bence \u00d6lveczky<\/p><\/figcaption><\/figure>\n\n\t<div class=\"article-header__content\">\n\t\t\t<a\n\t\t\tclass=\"article-header__category\"\n\t\t\thref=\"https:\/\/news.harvard.edu\/gazette\/section\/health\/\"\n\t\t>\n\t\t\tHealth\t\t<\/a>\n\t\t\n\t\t<h1 class=\"article-header__title wp-block-heading \">\n\t\tCreatures of habit\t<\/h1>\n\n\t\n\t\t\t<\/div>\n\t\t\n\t<div class=\"article-header__meta\">\n\t\t<div class=\"wp-block-post-author\">\n\t\t\t<address class=\"wp-block-post-author__content\">\n\t\t\t\t\t<p class=\"author wp-block-post-author__name\">\n\t\tPeter Reuell\t<\/p>\n\t\t\t<p class=\"wp-block-post-author__byline\">\n\t\t\tHarvard Staff Writer\t\t<\/p>\n\t\t\t\t\t<\/address>\n\t\t<\/div>\n\n\t\t<time class=\"article-header__date\" datetime=\"2015-05-06\">\n\t\t\tMay 6, 2015\t\t<\/time>\n\n\t\t<span class=\"article-header__reading-time\">\n\t\t\t7 min read\t\t<\/span>\n\t<\/div>\n\n\t\n\t\t\t<h2 class=\"article-header__subheading wp-block-heading\">\n\t\t\tMotor cortex is critical to learn new skills, but may not be needed to perform them, study says\t\t<\/h2>\n\t\t\n<\/header>\n"},"2":{"blockName":"core\/group","attrs":{"templateLock":false,"metadata":{"name":"Article content"},"align":"wide","layout":{"type":"constrained","justifyContent":"center"},"tagName":"div","lock":[],"className":"","style":[],"backgroundColor":"","textColor":"","gradient":"","fontSize":"","fontFamily":"","borderColor":"","ariaLabel":"","anchor":""},"innerBlocks":[{"blockName":"core\/freeform","attrs":{"content":"","lock":[],"metadata":[]},"innerBlocks":[],"innerHTML":"\n\t\t<p>When he set out to understand how the motor cortex changes with learning, Bence \u00d6lveczky, the John L. Loeb Associate Professor of the Natural Sciences, assumed, like nearly all other scientists, that unique learned motor behaviors originate in the motor cortex.<\/p>\n<p>What he found, however, was the opposite.<\/p>\n<p>To their surprise, \u00d6lveczky and his colleagues learned that while the brain\u2019s motor cortex is critically important for learning new skills, those skills, once learned, can be executed without any input from the motor cortex. The study is described in a paper published today in the journal Neuron.<\/p>\n<p>\u201cThe thinking has always been that the more primitive subcortical circuits are there to support innate, instinctive behaviors, while sophisticated, learned behaviors require the motor cortex,\u201d \u00d6lveczky said. \u201cOur assumption was that \u2026 when you perform a learned skill you sequence or coordinate it from the motor cortex. But in our experiments we found that even if the motor cortex was missing, there was no effect on complex learned motor sequences, so we have to conclude that subcortical circuits have the capacity to store and execute them.\u201d<\/p>\n<p>For many creatures, the ability to learn unique motor behaviors is a crucial adaptation. That\u2019s what allows humans to walk and talk, songbirds to sing, and predators to outsmart their prey. Virtually all of these behaviors are learned the same way, through trial and error.<\/p>\n<p>\u201cEssentially, you learn something by varying different aspects of your behavior and learning what works and what doesn\u2019t,\u201d \u00d6lveczky explained. \u201cWith time and much practice, the nervous system can select the actions that lead to good outcomes.\u201d<\/p>\n<p>As an example, \u00d6lveczky pointed to tennis players. While beginners often show large variation in their serves, the motions of experienced players are nearly identical from one serve to the next.<\/p>\n<p>To better understand the role that the motor cortex plays in the mastery of such skills, \u00d6lveczky and his colleagues developed a simple task that rewarded rats for pressing a lever, and then pressing it again 700 milliseconds later.<\/p>\n<p>Just as in any other trial-and-error learning scenario, the rats were initially rewarded for a wide range of lever presses. Over time, the contingency for success narrowed until only lever presses that were exactly 700 milliseconds apart were rewarded. Eventually, over 10,000 to 15,000 trials, each of the dozen rats in the experiment learned motor sequences equal to the task.<\/p>\n<p>Just as each player\u2019s serve in tennis is different, the rats solved the task in idiosyncratic ways, using precise sequences of seemingly arbitrary actions \u2014 from scratching the wall to a motion similar to a DJ spinning a record \u2014 to stick to the proper timing between lever presses.<\/p>\n","innerContent":["\n\t\t<p>When he set out to understand how the motor cortex changes with learning, Bence \u00d6lveczky, the John L. Loeb Associate Professor of the Natural Sciences, assumed, like nearly all other scientists, that unique learned motor behaviors originate in the motor cortex.<\/p>\n<p>What he found, however, was the opposite.<\/p>\n<p>To their surprise, \u00d6lveczky and his colleagues learned that while the brain\u2019s motor cortex is critically important for learning new skills, those skills, once learned, can be executed without any input from the motor cortex. The study is described in a paper published today in the journal Neuron.<\/p>\n<p>\u201cThe thinking has always been that the more primitive subcortical circuits are there to support innate, instinctive behaviors, while sophisticated, learned behaviors require the motor cortex,\u201d \u00d6lveczky said. \u201cOur assumption was that \u2026 when you perform a learned skill you sequence or coordinate it from the motor cortex. But in our experiments we found that even if the motor cortex was missing, there was no effect on complex learned motor sequences, so we have to conclude that subcortical circuits have the capacity to store and execute them.\u201d<\/p>\n<p>For many creatures, the ability to learn unique motor behaviors is a crucial adaptation. That\u2019s what allows humans to walk and talk, songbirds to sing, and predators to outsmart their prey. Virtually all of these behaviors are learned the same way, through trial and error.<\/p>\n<p>\u201cEssentially, you learn something by varying different aspects of your behavior and learning what works and what doesn\u2019t,\u201d \u00d6lveczky explained. \u201cWith time and much practice, the nervous system can select the actions that lead to good outcomes.\u201d<\/p>\n<p>As an example, \u00d6lveczky pointed to tennis players. While beginners often show large variation in their serves, the motions of experienced players are nearly identical from one serve to the next.<\/p>\n<p>To better understand the role that the motor cortex plays in the mastery of such skills, \u00d6lveczky and his colleagues developed a simple task that rewarded rats for pressing a lever, and then pressing it again 700 milliseconds later.<\/p>\n<p>Just as in any other trial-and-error learning scenario, the rats were initially rewarded for a wide range of lever presses. Over time, the contingency for success narrowed until only lever presses that were exactly 700 milliseconds apart were rewarded. Eventually, over 10,000 to 15,000 trials, each of the dozen rats in the experiment learned motor sequences equal to the task.<\/p>\n<p>Just as each player\u2019s serve in tennis is different, the rats solved the task in idiosyncratic ways, using precise sequences of seemingly arbitrary actions \u2014 from scratching the wall to a motion similar to a DJ spinning a record \u2014 to stick to the proper timing between lever presses.<\/p>\n"],"rendered":"\n\t\t<p>When he set out to understand how the motor cortex changes with learning, Bence \u00d6lveczky, the John L. Loeb Associate Professor of the Natural Sciences, assumed, like nearly all other scientists, that unique learned motor behaviors originate in the motor cortex.<\/p>\n<p>What he found, however, was the opposite.<\/p>\n<p>To their surprise, \u00d6lveczky and his colleagues learned that while the brain\u2019s motor cortex is critically important for learning new skills, those skills, once learned, can be executed without any input from the motor cortex. The study is described in a paper published today in the journal Neuron.<\/p>\n<p>\u201cThe thinking has always been that the more primitive subcortical circuits are there to support innate, instinctive behaviors, while sophisticated, learned behaviors require the motor cortex,\u201d \u00d6lveczky said. \u201cOur assumption was that \u2026 when you perform a learned skill you sequence or coordinate it from the motor cortex. But in our experiments we found that even if the motor cortex was missing, there was no effect on complex learned motor sequences, so we have to conclude that subcortical circuits have the capacity to store and execute them.\u201d<\/p>\n<p>For many creatures, the ability to learn unique motor behaviors is a crucial adaptation. That\u2019s what allows humans to walk and talk, songbirds to sing, and predators to outsmart their prey. Virtually all of these behaviors are learned the same way, through trial and error.<\/p>\n<p>\u201cEssentially, you learn something by varying different aspects of your behavior and learning what works and what doesn\u2019t,\u201d \u00d6lveczky explained. \u201cWith time and much practice, the nervous system can select the actions that lead to good outcomes.\u201d<\/p>\n<p>As an example, \u00d6lveczky pointed to tennis players. While beginners often show large variation in their serves, the motions of experienced players are nearly identical from one serve to the next.<\/p>\n<p>To better understand the role that the motor cortex plays in the mastery of such skills, \u00d6lveczky and his colleagues developed a simple task that rewarded rats for pressing a lever, and then pressing it again 700 milliseconds later.<\/p>\n<p>Just as in any other trial-and-error learning scenario, the rats were initially rewarded for a wide range of lever presses. Over time, the contingency for success narrowed until only lever presses that were exactly 700 milliseconds apart were rewarded. Eventually, over 10,000 to 15,000 trials, each of the dozen rats in the experiment learned motor sequences equal to the task.<\/p>\n<p>Just as each player\u2019s serve in tennis is different, the rats solved the task in idiosyncratic ways, using precise sequences of seemingly arbitrary actions \u2014 from scratching the wall to a motion similar to a DJ spinning a record \u2014 to stick to the proper timing between lever presses.<\/p>\n"},{"blockName":"core\/embed","attrs":{"url":"http:\/\/Two%20rats%20that%20have%20learned%20the%20timed%20lever-pressing%20task%20are%20seen%20performing%20it%20before%20and%20after%20lesions%20to%20the%20motor%20cortex.%20To%20the%20left%20are%20two%20examples%20taken%20before%20the%20lesion;%20on%20the%20right%20are%20two%20examples%20from%20the%20first%20day%20of%20training%20after%20the%20lesion.%20Note%20the%20stereotyped%20idiosyncratic%20behaviors%20and%20how%20they%20are%20not%20affected%20by%20motor%20cortex%20lesions.%20Videos%20are%20slowed%20down%20by%20a%20factor%20of%202.5.\u00a0%20Courtesy%20of%20Bence%20\u00d6lveczky","type":"video","responsive":true,"caption":"Two rats that have learned the timed lever-pressing task are seen performing it before and after lesions to the motor cortex. To the left are two examples taken before the lesion; on the right are two examples from the first day of training after the lesion. Note the stereotyped idiosyncratic behaviors and how they are not affected by motor cortex lesions. Videos are slowed down by a factor of 2.5.\u00a0 Courtesy of Bence \u00d6lveczky","providerNameSlug":"","allowResponsive":true,"previewable":true,"lock":[],"metadata":[],"align":"","className":"","style":[]},"innerBlocks":[],"innerHTML":"\n<figure class=\"wp-block-embed is-type-video is-provider-none wp-block-embed-none\"><div class=\"wp-block-embed__wrapper\">\nhttp:\/\/Two%20rats%20that%20have%20learned%20the%20timed%20lever-pressing%20task%20are%20seen%20performing%20it%20before%20and%20after%20lesions%20to%20the%20motor%20cortex.%20To%20the%20left%20are%20two%20examples%20taken%20before%20the%20lesion;%20on%20the%20right%20are%20two%20examples%20from%20the%20first%20day%20of%20training%20after%20the%20lesion.%20Note%20the%20stereotyped%20idiosyncratic%20behaviors%20and%20how%20they%20are%20not%20affected%20by%20motor%20cortex%20lesions.%20Videos%20are%20slowed%20down%20by%20a%20factor%20of%202.5.\u00a0%20Courtesy%20of%20Bence%20\u00d6lveczky\n<\/div>\n<figcaption class=\"wp-element-caption\">Two rats that have learned the timed lever-pressing task are seen performing it before and after lesions to the motor cortex. To the left are two examples taken before the lesion; on the right are two examples from the first day of training after the lesion. Note the stereotyped idiosyncratic behaviors and how they are not affected by motor cortex lesions. Videos are slowed down by a factor of 2.5.\u00a0 Courtesy of Bence \u00d6lveczky<\/figcaption><\/figure>\n","innerContent":["\n<figure class=\"wp-block-embed is-type-video is-provider-none wp-block-embed-none\"><div class=\"wp-block-embed__wrapper\">\nhttp:\/\/Two%20rats%20that%20have%20learned%20the%20timed%20lever-pressing%20task%20are%20seen%20performing%20it%20before%20and%20after%20lesions%20to%20the%20motor%20cortex.%20To%20the%20left%20are%20two%20examples%20taken%20before%20the%20lesion;%20on%20the%20right%20are%20two%20examples%20from%20the%20first%20day%20of%20training%20after%20the%20lesion.%20Note%20the%20stereotyped%20idiosyncratic%20behaviors%20and%20how%20they%20are%20not%20affected%20by%20motor%20cortex%20lesions.%20Videos%20are%20slowed%20down%20by%20a%20factor%20of%202.5.\u00a0%20Courtesy%20of%20Bence%20\u00d6lveczky\n<\/div>\n<figcaption class=\"wp-element-caption\">Two rats that have learned the timed lever-pressing task are seen performing it before and after lesions to the motor cortex. To the left are two examples taken before the lesion; on the right are two examples from the first day of training after the lesion. Note the stereotyped idiosyncratic behaviors and how they are not affected by motor cortex lesions. Videos are slowed down by a factor of 2.5.\u00a0 Courtesy of Bence \u00d6lveczky<\/figcaption><\/figure>\n"],"rendered":"\n<figure class=\"wp-block-embed is-type-video is-provider-none wp-block-embed-none\"><div class=\"wp-block-embed__wrapper\">\nhttp:\/\/Two%20rats%20that%20have%20learned%20the%20timed%20lever-pressing%20task%20are%20seen%20performing%20it%20before%20and%20after%20lesions%20to%20the%20motor%20cortex.%20To%20the%20left%20are%20two%20examples%20taken%20before%20the%20lesion;%20on%20the%20right%20are%20two%20examples%20from%20the%20first%20day%20of%20training%20after%20the%20lesion.%20Note%20the%20stereotyped%20idiosyncratic%20behaviors%20and%20how%20they%20are%20not%20affected%20by%20motor%20cortex%20lesions.%20Videos%20are%20slowed%20down%20by%20a%20factor%20of%202.5.\u00a0%20Courtesy%20of%20Bence%20\u00d6lveczky\n<\/div>\n<figcaption class=\"wp-element-caption\">Two rats that have learned the timed lever-pressing task are seen performing it before and after lesions to the motor cortex. To the left are two examples taken before the lesion; on the right are two examples from the first day of training after the lesion. Note the stereotyped idiosyncratic behaviors and how they are not affected by motor cortex lesions. Videos are slowed down by a factor of 2.5.\u00a0 Courtesy of Bence \u00d6lveczky<\/figcaption><\/figure>\n"},{"blockName":"core\/freeform","attrs":{"content":"","lock":[],"metadata":[]},"innerBlocks":[],"innerHTML":"\n<p>\u201cI assume that they didn\u2019t know it was an interval timing task, but through trial and error the rats learned that if they produce a particular sequence of movements they will get a nice big drop of water,\u201d \u00d6lveczky said. \u201cAnd, importantly, once they have this figured out, the behavior is very stable and it\u2019s very hard to change because they would be changing from something that works.\u201d<\/p>\n<p>When \u00d6lveczky and colleagues lesioned the rats\u2019 motor cortices and returned them to the experiment, they were surprised to find that the rats were able to complete the task just as they had earlier, using exactly the same movements.<\/p>\n<p>\u201cWe were very puzzled, since we all thought that these learned behaviors should require the motor cortex,\u201d \u00d6lveczky said. \u201cSo we thought, what have we been missing?\u201d<\/p>\n<p>To find an answer, \u00d6lveczky and his colleagues began sifting through the literature on the motor cortex and discovered that the widely held assumption that learned motor skills are stored in the motor cortex was largely based on studies that had focused on fine motor skills.<\/p>\n<p>\u201cIf you lesion the motor cortex in those cases, performance is affected, often quite severely,\u201d \u00d6lveczky said. \u201cIn many mammals, including humans, we need the motor cortex to produce fine dexterous movements and skills.<\/p>\n<p>\u201cThe problem was that many people, including us, were generalizing from these studies, leaving us convinced that the motor cortex is important for all kinds of skills.\u201d he continued. \u201cBut no. It\u2019s not that the motor cortex is necessary for executing learned motor sequences, per se. It\u2019s important for dexterity, but that\u2019s a different aspect of motor skill than the one we were interested in.\u201d<\/p>\n<p>While the evidence suggested that the motor cortex is not necessary to perform the learned behaviors, \u00d6lveczky and his colleagues set out to test whether it was needed to learn them in the first place by lesioning rats\u2019 motor cortices before exposing them to the task.<\/p>\n<p>\u201cInitially, they were no different than the other rats,\u201d \u00d6lveczky said. \u201cThey pressed the lever the same, they had the same sort of movements, but lesioned rats never got there. We kept training them for many months, but their variability remained high. They never learned the task.<\/p>\n<p>\u201cRats that have already learned the task don\u2019t need the motor cortex,\u201d he added. \u201cBut to learn it initially, the motor cortex is absolutely necessary. It suggests that the motor cortex is a tutor that uses its superior knowledge to instruct subcortical circuits how to perform new tricks. And when these circuits get to the point where they can do the same thing every time, then the motor cortex becomes dispensable.\u201d<\/p>\n<p>While the study sheds new light on the role of the motor cortex in learning and performing motor skills, it also serves to highlight the previously unrecognized power of subcortical motor circuits, \u00d6lveczky said.<\/p>\n<p>\u201cLizards and other non-mammals are all capable of extraordinary motor feats, but none of them have a cortex,\u201d \u00d6lveczky said. \u201cOne way of thinking about this is that when mammals evolved a cortex, there was already a very impressive motor infrastructure in place, one that had been refined over millions and millions of years. But it was adapted for specific scenarios and lacked flexibility.<\/p>\n<p>\u201cTo increase the flexibility of the animal\u2019s behavior and allow it to learn new skills, the cortex had basically two options. It could integrate itself into what was already there, or it could reinvent everything and take full control over the animal\u2019s movements. Our results suggest that the cortex was smart and found ways to use the subcortical motor controllers to its advantage. There are now pathways in the brain that allow the motor cortex to influence and reprogram subcortical circuits to increase their utility and flexibility. Offloading the execution of stereotyped motor behaviors to these lower-level circuits frees up the motor cortex to do more sophisticated things.\u201d<\/p>\n\n","innerContent":["\n<p>\u201cI assume that they didn\u2019t know it was an interval timing task, but through trial and error the rats learned that if they produce a particular sequence of movements they will get a nice big drop of water,\u201d \u00d6lveczky said. \u201cAnd, importantly, once they have this figured out, the behavior is very stable and it\u2019s very hard to change because they would be changing from something that works.\u201d<\/p>\n<p>When \u00d6lveczky and colleagues lesioned the rats\u2019 motor cortices and returned them to the experiment, they were surprised to find that the rats were able to complete the task just as they had earlier, using exactly the same movements.<\/p>\n<p>\u201cWe were very puzzled, since we all thought that these learned behaviors should require the motor cortex,\u201d \u00d6lveczky said. \u201cSo we thought, what have we been missing?\u201d<\/p>\n<p>To find an answer, \u00d6lveczky and his colleagues began sifting through the literature on the motor cortex and discovered that the widely held assumption that learned motor skills are stored in the motor cortex was largely based on studies that had focused on fine motor skills.<\/p>\n<p>\u201cIf you lesion the motor cortex in those cases, performance is affected, often quite severely,\u201d \u00d6lveczky said. \u201cIn many mammals, including humans, we need the motor cortex to produce fine dexterous movements and skills.<\/p>\n<p>\u201cThe problem was that many people, including us, were generalizing from these studies, leaving us convinced that the motor cortex is important for all kinds of skills.\u201d he continued. \u201cBut no. It\u2019s not that the motor cortex is necessary for executing learned motor sequences, per se. It\u2019s important for dexterity, but that\u2019s a different aspect of motor skill than the one we were interested in.\u201d<\/p>\n<p>While the evidence suggested that the motor cortex is not necessary to perform the learned behaviors, \u00d6lveczky and his colleagues set out to test whether it was needed to learn them in the first place by lesioning rats\u2019 motor cortices before exposing them to the task.<\/p>\n<p>\u201cInitially, they were no different than the other rats,\u201d \u00d6lveczky said. \u201cThey pressed the lever the same, they had the same sort of movements, but lesioned rats never got there. We kept training them for many months, but their variability remained high. They never learned the task.<\/p>\n<p>\u201cRats that have already learned the task don\u2019t need the motor cortex,\u201d he added. \u201cBut to learn it initially, the motor cortex is absolutely necessary. It suggests that the motor cortex is a tutor that uses its superior knowledge to instruct subcortical circuits how to perform new tricks. And when these circuits get to the point where they can do the same thing every time, then the motor cortex becomes dispensable.\u201d<\/p>\n<p>While the study sheds new light on the role of the motor cortex in learning and performing motor skills, it also serves to highlight the previously unrecognized power of subcortical motor circuits, \u00d6lveczky said.<\/p>\n<p>\u201cLizards and other non-mammals are all capable of extraordinary motor feats, but none of them have a cortex,\u201d \u00d6lveczky said. \u201cOne way of thinking about this is that when mammals evolved a cortex, there was already a very impressive motor infrastructure in place, one that had been refined over millions and millions of years. But it was adapted for specific scenarios and lacked flexibility.<\/p>\n<p>\u201cTo increase the flexibility of the animal\u2019s behavior and allow it to learn new skills, the cortex had basically two options. It could integrate itself into what was already there, or it could reinvent everything and take full control over the animal\u2019s movements. Our results suggest that the cortex was smart and found ways to use the subcortical motor controllers to its advantage. There are now pathways in the brain that allow the motor cortex to influence and reprogram subcortical circuits to increase their utility and flexibility. Offloading the execution of stereotyped motor behaviors to these lower-level circuits frees up the motor cortex to do more sophisticated things.\u201d<\/p>\n\n"],"rendered":"\n<p>\u201cI assume that they didn\u2019t know it was an interval timing task, but through trial and error the rats learned that if they produce a particular sequence of movements they will get a nice big drop of water,\u201d \u00d6lveczky said. \u201cAnd, importantly, once they have this figured out, the behavior is very stable and it\u2019s very hard to change because they would be changing from something that works.\u201d<\/p>\n<p>When \u00d6lveczky and colleagues lesioned the rats\u2019 motor cortices and returned them to the experiment, they were surprised to find that the rats were able to complete the task just as they had earlier, using exactly the same movements.<\/p>\n<p>\u201cWe were very puzzled, since we all thought that these learned behaviors should require the motor cortex,\u201d \u00d6lveczky said. \u201cSo we thought, what have we been missing?\u201d<\/p>\n<p>To find an answer, \u00d6lveczky and his colleagues began sifting through the literature on the motor cortex and discovered that the widely held assumption that learned motor skills are stored in the motor cortex was largely based on studies that had focused on fine motor skills.<\/p>\n<p>\u201cIf you lesion the motor cortex in those cases, performance is affected, often quite severely,\u201d \u00d6lveczky said. \u201cIn many mammals, including humans, we need the motor cortex to produce fine dexterous movements and skills.<\/p>\n<p>\u201cThe problem was that many people, including us, were generalizing from these studies, leaving us convinced that the motor cortex is important for all kinds of skills.\u201d he continued. \u201cBut no. It\u2019s not that the motor cortex is necessary for executing learned motor sequences, per se. It\u2019s important for dexterity, but that\u2019s a different aspect of motor skill than the one we were interested in.\u201d<\/p>\n<p>While the evidence suggested that the motor cortex is not necessary to perform the learned behaviors, \u00d6lveczky and his colleagues set out to test whether it was needed to learn them in the first place by lesioning rats\u2019 motor cortices before exposing them to the task.<\/p>\n<p>\u201cInitially, they were no different than the other rats,\u201d \u00d6lveczky said. \u201cThey pressed the lever the same, they had the same sort of movements, but lesioned rats never got there. We kept training them for many months, but their variability remained high. They never learned the task.<\/p>\n<p>\u201cRats that have already learned the task don\u2019t need the motor cortex,\u201d he added. \u201cBut to learn it initially, the motor cortex is absolutely necessary. It suggests that the motor cortex is a tutor that uses its superior knowledge to instruct subcortical circuits how to perform new tricks. And when these circuits get to the point where they can do the same thing every time, then the motor cortex becomes dispensable.\u201d<\/p>\n<p>While the study sheds new light on the role of the motor cortex in learning and performing motor skills, it also serves to highlight the previously unrecognized power of subcortical motor circuits, \u00d6lveczky said.<\/p>\n<p>\u201cLizards and other non-mammals are all capable of extraordinary motor feats, but none of them have a cortex,\u201d \u00d6lveczky said. \u201cOne way of thinking about this is that when mammals evolved a cortex, there was already a very impressive motor infrastructure in place, one that had been refined over millions and millions of years. But it was adapted for specific scenarios and lacked flexibility.<\/p>\n<p>\u201cTo increase the flexibility of the animal\u2019s behavior and allow it to learn new skills, the cortex had basically two options. It could integrate itself into what was already there, or it could reinvent everything and take full control over the animal\u2019s movements. Our results suggest that the cortex was smart and found ways to use the subcortical motor controllers to its advantage. There are now pathways in the brain that allow the motor cortex to influence and reprogram subcortical circuits to increase their utility and flexibility. Offloading the execution of stereotyped motor behaviors to these lower-level circuits frees up the motor cortex to do more sophisticated things.\u201d<\/p>\n\n"}],"innerHTML":"\n<div class=\"wp-block-group alignwide\">\n\n\r\n\n\r\n\n\n<\/div>\n","innerContent":["\n<div class=\"wp-block-group alignwide\">\n\n","\r\n","\n\r\n","\n\n<\/div>\n"],"rendered":"\n<div class=\"wp-block-group alignwide has-global-padding is-content-justification-center is-layout-constrained wp-block-group-is-layout-constrained\">\n\n\n\t\t<p>When he set out to understand how the motor cortex changes with learning, Bence \u00d6lveczky, the John L. Loeb Associate Professor of the Natural Sciences, assumed, like nearly all other scientists, that unique learned motor behaviors originate in the motor cortex.<\/p>\n<p>What he found, however, was the opposite.<\/p>\n<p>To their surprise, \u00d6lveczky and his colleagues learned that while the brain\u2019s motor cortex is critically important for learning new skills, those skills, once learned, can be executed without any input from the motor cortex. The study is described in a paper published today in the journal Neuron.<\/p>\n<p>\u201cThe thinking has always been that the more primitive subcortical circuits are there to support innate, instinctive behaviors, while sophisticated, learned behaviors require the motor cortex,\u201d \u00d6lveczky said. \u201cOur assumption was that \u2026 when you perform a learned skill you sequence or coordinate it from the motor cortex. But in our experiments we found that even if the motor cortex was missing, there was no effect on complex learned motor sequences, so we have to conclude that subcortical circuits have the capacity to store and execute them.\u201d<\/p>\n<p>For many creatures, the ability to learn unique motor behaviors is a crucial adaptation. That\u2019s what allows humans to walk and talk, songbirds to sing, and predators to outsmart their prey. Virtually all of these behaviors are learned the same way, through trial and error.<\/p>\n<p>\u201cEssentially, you learn something by varying different aspects of your behavior and learning what works and what doesn\u2019t,\u201d \u00d6lveczky explained. \u201cWith time and much practice, the nervous system can select the actions that lead to good outcomes.\u201d<\/p>\n<p>As an example, \u00d6lveczky pointed to tennis players. While beginners often show large variation in their serves, the motions of experienced players are nearly identical from one serve to the next.<\/p>\n<p>To better understand the role that the motor cortex plays in the mastery of such skills, \u00d6lveczky and his colleagues developed a simple task that rewarded rats for pressing a lever, and then pressing it again 700 milliseconds later.<\/p>\n<p>Just as in any other trial-and-error learning scenario, the rats were initially rewarded for a wide range of lever presses. Over time, the contingency for success narrowed until only lever presses that were exactly 700 milliseconds apart were rewarded. Eventually, over 10,000 to 15,000 trials, each of the dozen rats in the experiment learned motor sequences equal to the task.<\/p>\n<p>Just as each player\u2019s serve in tennis is different, the rats solved the task in idiosyncratic ways, using precise sequences of seemingly arbitrary actions \u2014 from scratching the wall to a motion similar to a DJ spinning a record \u2014 to stick to the proper timing between lever presses.<\/p>\n\r\n\n<figure class=\"wp-block-embed is-type-video is-provider-none wp-block-embed-none\"><div class=\"wp-block-embed__wrapper\">\nhttp:\/\/Two%20rats%20that%20have%20learned%20the%20timed%20lever-pressing%20task%20are%20seen%20performing%20it%20before%20and%20after%20lesions%20to%20the%20motor%20cortex.%20To%20the%20left%20are%20two%20examples%20taken%20before%20the%20lesion;%20on%20the%20right%20are%20two%20examples%20from%20the%20first%20day%20of%20training%20after%20the%20lesion.%20Note%20the%20stereotyped%20idiosyncratic%20behaviors%20and%20how%20they%20are%20not%20affected%20by%20motor%20cortex%20lesions.%20Videos%20are%20slowed%20down%20by%20a%20factor%20of%202.5.\u00a0%20Courtesy%20of%20Bence%20\u00d6lveczky\n<\/div>\n<figcaption class=\"wp-element-caption\">Two rats that have learned the timed lever-pressing task are seen performing it before and after lesions to the motor cortex. To the left are two examples taken before the lesion; on the right are two examples from the first day of training after the lesion. Note the stereotyped idiosyncratic behaviors and how they are not affected by motor cortex lesions. Videos are slowed down by a factor of 2.5.\u00a0 Courtesy of Bence \u00d6lveczky<\/figcaption><\/figure>\n\n\r\n\n<p>\u201cI assume that they didn\u2019t know it was an interval timing task, but through trial and error the rats learned that if they produce a particular sequence of movements they will get a nice big drop of water,\u201d \u00d6lveczky said. \u201cAnd, importantly, once they have this figured out, the behavior is very stable and it\u2019s very hard to change because they would be changing from something that works.\u201d<\/p>\n<p>When \u00d6lveczky and colleagues lesioned the rats\u2019 motor cortices and returned them to the experiment, they were surprised to find that the rats were able to complete the task just as they had earlier, using exactly the same movements.<\/p>\n<p>\u201cWe were very puzzled, since we all thought that these learned behaviors should require the motor cortex,\u201d \u00d6lveczky said. \u201cSo we thought, what have we been missing?\u201d<\/p>\n<p>To find an answer, \u00d6lveczky and his colleagues began sifting through the literature on the motor cortex and discovered that the widely held assumption that learned motor skills are stored in the motor cortex was largely based on studies that had focused on fine motor skills.<\/p>\n<p>\u201cIf you lesion the motor cortex in those cases, performance is affected, often quite severely,\u201d \u00d6lveczky said. \u201cIn many mammals, including humans, we need the motor cortex to produce fine dexterous movements and skills.<\/p>\n<p>\u201cThe problem was that many people, including us, were generalizing from these studies, leaving us convinced that the motor cortex is important for all kinds of skills.\u201d he continued. \u201cBut no. It\u2019s not that the motor cortex is necessary for executing learned motor sequences, per se. It\u2019s important for dexterity, but that\u2019s a different aspect of motor skill than the one we were interested in.\u201d<\/p>\n<p>While the evidence suggested that the motor cortex is not necessary to perform the learned behaviors, \u00d6lveczky and his colleagues set out to test whether it was needed to learn them in the first place by lesioning rats\u2019 motor cortices before exposing them to the task.<\/p>\n<p>\u201cInitially, they were no different than the other rats,\u201d \u00d6lveczky said. \u201cThey pressed the lever the same, they had the same sort of movements, but lesioned rats never got there. We kept training them for many months, but their variability remained high. They never learned the task.<\/p>\n<p>\u201cRats that have already learned the task don\u2019t need the motor cortex,\u201d he added. \u201cBut to learn it initially, the motor cortex is absolutely necessary. It suggests that the motor cortex is a tutor that uses its superior knowledge to instruct subcortical circuits how to perform new tricks. And when these circuits get to the point where they can do the same thing every time, then the motor cortex becomes dispensable.\u201d<\/p>\n<p>While the study sheds new light on the role of the motor cortex in learning and performing motor skills, it also serves to highlight the previously unrecognized power of subcortical motor circuits, \u00d6lveczky said.<\/p>\n<p>\u201cLizards and other non-mammals are all capable of extraordinary motor feats, but none of them have a cortex,\u201d \u00d6lveczky said. \u201cOne way of thinking about this is that when mammals evolved a cortex, there was already a very impressive motor infrastructure in place, one that had been refined over millions and millions of years. But it was adapted for specific scenarios and lacked flexibility.<\/p>\n<p>\u201cTo increase the flexibility of the animal\u2019s behavior and allow it to learn new skills, the cortex had basically two options. It could integrate itself into what was already there, or it could reinvent everything and take full control over the animal\u2019s movements. Our results suggest that the cortex was smart and found ways to use the subcortical motor controllers to its advantage. There are now pathways in the brain that allow the motor cortex to influence and reprogram subcortical circuits to increase their utility and flexibility. Offloading the execution of stereotyped motor behaviors to these lower-level circuits frees up the motor cortex to do more sophisticated things.\u201d<\/p>\n\n\n\n<\/div>\n"}},"jetpack-related-posts":[{"id":60609,"url":"https:\/\/news.harvard.edu\/gazette\/story\/2007\/11\/cerebral-cortex-thicker-in-people-with-migraines\/","url_meta":{"origin":169877,"position":0},"title":"Cerebral cortex thicker in people with migraines","author":"harvardgazette","date":"November 19, 2007","format":false,"excerpt":"People who suffer from migraine headaches have differences in an area of the brain that helps process sensory information, including pain, according to a study published in the November 20, 2007, issue of Neurology, the medical journal of the American Academy of Neurology. The study found that part of the\u2026","rel":"","context":"In "Health"","block_context":{"text":"Health","link":"https:\/\/news.harvard.edu\/gazette\/section\/health\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":310223,"url":"https:\/\/news.harvard.edu\/gazette\/story\/2020\/08\/harvard-scientists-find-vision-relates-to-movement\/","url_meta":{"origin":169877,"position":1},"title":"Linking sight and movement","author":"gazettebeckycoleman","date":"August 11, 2020","format":false,"excerpt":"Harvard neuroscientists look at how movement influences vision and perception.","rel":"","context":"In "Science & Tech"","block_context":{"text":"Science & Tech","link":"https:\/\/news.harvard.edu\/gazette\/section\/science-technology\/"},"img":{"alt_text":"Rat brain scan.","src":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2020\/08\/2018_05_22__RecognizedCode-2-2_s2c12_H_2500.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2020\/08\/2018_05_22__RecognizedCode-2-2_s2c12_H_2500.jpg?resize=350%2C200 1x, https:\/\/news.harvard.edu\/wp-content\/uploads\/2020\/08\/2018_05_22__RecognizedCode-2-2_s2c12_H_2500.jpg?resize=525%2C300 1.5x, https:\/\/news.harvard.edu\/wp-content\/uploads\/2020\/08\/2018_05_22__RecognizedCode-2-2_s2c12_H_2500.jpg?resize=700%2C400 2x"},"classes":[]},{"id":57528,"url":"https:\/\/news.harvard.edu\/gazette\/story\/2001\/11\/commoner-in-brain-crowns-the-cortex\/","url_meta":{"origin":169877,"position":2},"title":"“Commoner” in brain crowns the cortex","author":"harvardgazette","date":"November 30, 2001","format":false,"excerpt":"With its role in higher cognitive functions, the cortex represents a significant evolutionary development in mammals, culminating in the enlarged hemispheres of humans and other primates. In the development of this crowning structure, neurons are guided by factors that are both genetic and environmental. A research team led by Christopher\u2026","rel":"","context":"In "Health"","block_context":{"text":"Health","link":"https:\/\/news.harvard.edu\/gazette\/section\/health\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":39910,"url":"https:\/\/news.harvard.edu\/gazette\/story\/2010\/03\/its-all-in-the-cortex\/","url_meta":{"origin":169877,"position":3},"title":"It\u2019s all in the cortex","author":"harvardgazette","date":"March 8, 2010","format":false,"excerpt":"Research suggests that the brain\u2019s lateral prefrontal cortex plays an important role in showing how well someone can rebound emotionally the day after an argument.","rel":"","context":"In "Health"","block_context":{"text":"Health","link":"https:\/\/news.harvard.edu\/gazette\/section\/health\/"},"img":{"alt_text":"","src":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2010\/03\/030310_conflict_2691.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2010\/03\/030310_conflict_2691.jpg?resize=350%2C200 1x, https:\/\/news.harvard.edu\/wp-content\/uploads\/2010\/03\/030310_conflict_2691.jpg?resize=525%2C300 1.5x"},"classes":[]},{"id":70612,"url":"https:\/\/news.harvard.edu\/gazette\/story\/2002\/07\/why-the-brains-of-humans-are-bigger\/","url_meta":{"origin":169877,"position":4},"title":"Why the brains of humans are bigger","author":"gazetteimport","date":"July 18, 2002","format":false,"excerpt":"Researchers have identified a protein that may help to explain why the brains cerebral cortex is disproportionately larger in humans than in other species, a finding that appears in the July 19 issue of Science and adds an important piece to the developing blueprint of the part of the brain\u2026","rel":"","context":"In "Campus & Community"","block_context":{"text":"Campus & Community","link":"https:\/\/news.harvard.edu\/gazette\/section\/campus-community\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":74029,"url":"https:\/\/news.harvard.edu\/gazette\/story\/2011\/02\/doing-the-neuron-tango\/","url_meta":{"origin":169877,"position":5},"title":"Doing the neuron tango","author":"harvardgazette","date":"February 23, 2011","format":false,"excerpt":"A group of Harvard Stem Cell Institute researchers in the Department of Stem Cell and Regenerative Biology has discovered that excitatory neurons control the positioning of inhibitory neurons in the brain in a process critically important for generating balanced circuitry and proper cortical response.","rel":"","context":"In "Health"","block_context":{"text":"Health","link":"https:\/\/news.harvard.edu\/gazette\/section\/health\/"},"img":{"alt_text":"","src":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2011\/02\/022211_neuron_253.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2011\/02\/022211_neuron_253.jpg?resize=350%2C200 1x, https:\/\/news.harvard.edu\/wp-content\/uploads\/2011\/02\/022211_neuron_253.jpg?resize=525%2C300 1.5x"},"classes":[]}],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/posts\/169877","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/users\/105622744"}],"replies":[{"embeddable":true,"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/comments?post=169877"}],"version-history":[{"count":1,"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/posts\/169877\/revisions"}],"predecessor-version":[{"id":267416,"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/posts\/169877\/revisions\/267416"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/media\/169922"}],"wp:attachment":[{"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/media?parent=169877"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/categories?post=169877"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/tags?post=169877"},{"taxonomy":"format","embeddable":true,"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/gazette-formats?post=169877"},{"taxonomy":"series","embeddable":true,"href":"https:\/\/news.harvard.edu\/gazette\/wp-json\/wp\/v2\/series?post=169877"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}