{"id":8085,"date":"2019-05-22T16:03:52","date_gmt":"2019-05-22T16:03:52","guid":{"rendered":"http:\/\/www.lancaster.ac.uk\/fas\/psych\/glossary\/grasp_response\/"},"modified":"2019-07-08T16:24:52","modified_gmt":"2019-07-08T16:24:52","slug":"grasp_response","status":"publish","type":"post","link":"https:\/\/www.lancaster.ac.uk\/fas\/psych\/glossary\/grasp_response\/","title":{"rendered":"Grasp response"},"content":{"rendered":"<p>Flexing of the fingers or toes when a newborn&#8217;s palm of the hand (palmar grasp) or sole (plantar grasp) of the foot is stimulated (see first figure below). \u00a0The power exerted by the healthy full term newborn performing the palmar grasp (also referred to as the palmar reflex) is evident in recordings made by John B. Watson and Myrtle B. McGraw many years ago (see second and third figures below). \u00a0When the palmar and plantar grasps are elicited in the newborn simultaneously, then it is possible for the infant to hang unsupported from a rope rather in the fashion of a sloth (see fourth figure below). \u00a0Both grasp response can be elicited in anencephalic infants (Paulson, G., &amp; Gottlieb, G. Developmental reflexes: the reappearance of foetal and neonatal reflexes in aged patients. <span class=\"\" style=\"font-style: italic;\">Brain<\/span>,<span class=\"\" style=\"font-style: italic;\"> 91<\/span>, 37-52, 1968). Such a finding supports the contention that palmar and plantar responses in the newborn are mediate by mechanisms at the spinal level, possibly involving interneurons. \u00a0Further support stems from the fact that both responses can be elicited as early as the gestational age of 25 weeks. \u00a0Whether these responses and other so-called reflexes continue to have functions in human development is matter of debate, with one view treating them as <a class=\"cc-route-enabled\" href=\"http:\/\/whyevolutionistrue.wordpress.com\/2014\/04\/08\/the-grasping-reflex-of-babies-a-vestigial-trait\/\" target=\"_self\" rel=\"noopener noreferrer\" data-editable-link=\"http:\/\/whyevolutionistrue.wordpress.com\/2014\/04\/08\/the-grasping-reflex-of-babies-a-vestigial-trait\/&amp;target=_self\">phylogenetic vestiges<\/a>. \u00a0Both responses have <a class=\"cc-route-enabled\" href=\"http:\/\/www.hindawi.com\/journals\/ijpedi\/2012\/191562\/#B37\" target=\"_self\" rel=\"noopener noreferrer\" data-editable-link=\"http:\/\/www.hindawi.com\/journals\/ijpedi\/2012\/191562\/#B37&amp;target=_self\">clinical relevance<\/a>, especially in the early detection of spasticity: athetoid cerebral palsy in the case of the palmar response and the plantar response with regard to spastic diplegia.<\/p>\n<p class=\"\" style=\"text-align: center;\">\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"..\/wp-content\/uploads\/2019\/05\/palmar-grasp.jpg\" \/><\/p>\n<p class=\"\" style=\"text-align: left;\">\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0a. \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0b.<\/p>\n<p class=\"\" style=\"text-align: center;\">Eliciting the palmar grasp (a) and plantar grasp (b) in the human newborn.<\/p>\n<p class=\"\" style=\"text-align: center;\">\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"..\/wp-content\/uploads\/2019\/05\/Watson-grasp.jpeg\" \/><\/p>\n<div class=\"\" style=\"text-align: center;\">John B. Watson and Rosalie Raynor eliciting newborn palmar grasp reflex (ca. 1916-1920). It was the avid Darwinist\u00a0<a class=\"cc-route-enabled\" href=\"http:\/\/query.nytimes.com\/mem\/archive-free\/pdf?res=9E05E6DF1538E233A25751C2A9639C94639ED7CF\" target=\"_self\" rel=\"noopener noreferrer\" data-editable-link=\"http:\/\/query.nytimes.com\/mem\/archive-free\/pdf?res=9E05E6DF1538E233A25751C2A9639C94639ED7CF?target=_self\">Louis Robinson<\/a> (1857-????) who first described in 1891 that the human newborn was able to support its own weight when holding on to a horizontal rod. Testing 60 infants under one month-of-age, he reported they could maintain the grasp for at least 10 seconds, with one infant doing so for 2 minutes and 35 seconds. See Robinson, L. Darwinism in the nursery. <span class=\"\" style=\"font-style: italic;\">Nineteenth Century<\/span>, 1891, <span class=\"\" style=\"font-style: italic;\">30<\/span>, 831-842.<\/div>\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"..\/wp-content\/uploads\/2019\/05\/McGraw-grasp-2.jpg\" \/><\/p>\n<p class=\"\" style=\"text-align: center;\">A frame grab from the <a class=\"cc-route-enabled\" href=\"https:\/\/www.youtube.com\/watch?v=jXJLaGguQiU\" target=\"_self\" rel=\"noopener noreferrer\" data-editable-link=\"https:\/\/www.youtube.com\/watch?v=jXJLaGguQiU?target=_self\">film<\/a> (1932) that accompanies the book by Myrtle B. McGraw <span class=\"\" style=\"font-style: italic;\">Growth: a study of Johnny and Jimmy<\/span>. New York: Appleton Century Crofts, 1935.<\/p>\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"..\/wp-content\/uploads\/2019\/05\/Newborn-grasp.jpeg\" \/><\/p>\n<p class=\"\" style=\"text-align: center;\">Human newborn hanging vertically (by means of the palmar grasp reflex) and upside down (by means of a simultaneous elicitation of the palmar and plantar reflexes), the latter comparing well with that of a sloth.<\/p>\n<p>\u00a0See <a href=\"anencephaly\">Anencephaly<\/a>, <a href=\"athetoid_-or_athetotiform-_movements\">Athetoid (or athetotiform) movements<\/a>, <a href=\"cerebral_palsy\">Cerebral palsy<\/a>, <a href=\"interneurons\">Interneurons<\/a>, <a href=\"palmar_grasp\">Palmar grasp<\/a>, <a href=\"pincer_grasp_-or_grip-\">Pincer grasp (or grip)<\/a>, <a href=\"prehension\">Prehension<\/a>, <a href=\"reflex\">Reflex<\/a>, <a href=\"spastic_diplegia\">Spastic diplegia<\/a>, <a href=\"spasticity\">Spasticity<\/a>, <a href=\"spinal_reflex\">Spinal reflex<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Flexing of the fingers or toes when a newborn&#8217;s palm of the hand (palmar grasp) or sole (plantar grasp) of the foot is stimulated (see first figure below). \u00a0The power exerted by the healthy full term newborn performing the palmar grasp (also referred to as the palmar reflex) is evident in recordings made by John &hellip; <\/p>\n<p class=\"link-more\"><a href=\"https:\/\/www.lancaster.ac.uk\/fas\/psych\/glossary\/grasp_response\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Grasp response&#8221;<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[2],"class_list":["post-8085","post","type-post","status-publish","format-standard","hentry","category-uncategorized","tag-glossary","entry"],"_links":{"self":[{"href":"https:\/\/www.lancaster.ac.uk\/fas\/psych\/glossary\/wp-json\/wp\/v2\/posts\/8085","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.lancaster.ac.uk\/fas\/psych\/glossary\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.lancaster.ac.uk\/fas\/psych\/glossary\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.lancaster.ac.uk\/fas\/psych\/glossary\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.lancaster.ac.uk\/fas\/psych\/glossary\/wp-json\/wp\/v2\/comments?post=8085"}],"version-history":[{"count":4,"href":"https:\/\/www.lancaster.ac.uk\/fas\/psych\/glossary\/wp-json\/wp\/v2\/posts\/8085\/revisions"}],"predecessor-version":[{"id":9534,"href":"https:\/\/www.lancaster.ac.uk\/fas\/psych\/glossary\/wp-json\/wp\/v2\/posts\/8085\/revisions\/9534"}],"wp:attachment":[{"href":"https:\/\/www.lancaster.ac.uk\/fas\/psych\/glossary\/wp-json\/wp\/v2\/media?parent=8085"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.lancaster.ac.uk\/fas\/psych\/glossary\/wp-json\/wp\/v2\/categories?post=8085"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.lancaster.ac.uk\/fas\/psych\/glossary\/wp-json\/wp\/v2\/tags?post=8085"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}