<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0016-3813</journal-id>
<journal-title><![CDATA[Gaceta médica de México]]></journal-title>
<abbrev-journal-title><![CDATA[Gac. Méd. Méx]]></abbrev-journal-title>
<issn>0016-3813</issn>
<publisher>
<publisher-name><![CDATA[Academia Nacional de Medicina de México A.C.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0016-38132019000500496</article-id>
<article-id pub-id-type="doi">10.24875/gmm.m20000338</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Sleep in the crustacean crayfish]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ramón y Romero]]></surname>
<given-names><![CDATA[Fidel]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Nacional Autónoma de México Faculty of Medicine Department of Physiology]]></institution>
<addr-line><![CDATA[Mexico City ]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>10</month>
<year>2019</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>10</month>
<year>2019</year>
</pub-date>
<volume>155</volume>
<numero>5</numero>
<fpage>496</fpage>
<lpage>499</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0016-38132019000500496&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0016-38132019000500496&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0016-38132019000500496&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[Sleep is defined as a state of unconsciousness, reduced locomotive activity and rapid awakening, and is well established in mammals, birds, reptiles and teleosts. Commonly, it is also defined with electrical records (electroencephalogram), which are only well established in mammals and to some extent in birds. However, sleep states similar to those of mammals, except for electrical criteria, appear to occur in some invertebrates. Currently, the most compelling evidence of sleep in invertebrates has been obtained in the crayfish. In mammals, sleep is characterized by a brain state that is different from that of wakefulness, which includes a change to slow waves that has not been observed in insects. Herein, we show that the crayfish enters a brain state with a high threshold to vibratory stimuli, accompanied by a form of slow wave activity in the brain, quite different from that of wakefulness. Therefore, the crayfish can enter a state of sleep that is comparable to that of mammals.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Sleep]]></kwd>
<kwd lng="en"><![CDATA[Slow wave activity in the brain]]></kwd>
<kwd lng="en"><![CDATA[Crustacean]]></kwd>
<kwd lng="en"><![CDATA[Brain]]></kwd>
</kwd-group>
</article-meta>
</front><back>
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