Tim Ryan (Ohio politician) and Morris water navigation task: Difference between pages

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In [[neuroscience]], the '''Morris water maze''' is a behavioral procedure designed to test [[spatial memory]]. It was developed by [[neuroscientist]] [[Richard Morris]] in [[1981]], and is commonly used today to explore the role of the [[hippocampus]] in the formation of [[spatial memory|spatial memories]].

:''For the actor, see [[Tim Ryan (actor)|Tim Ryan]]''

== Overview ==

'''Timothy J. Ryan''' (born [[July 16]], [[1973]]) is an [[United States of America|American]] politician of the [[United States Democratic Party|Democratic Party]], who is a [[United States House of Representatives|U.S. representative]] for the 17th congressional district of [[Ohio]] ([http://nationalatlas.gov/printable/images/preview/congdist/oh17_109.gif map]), serving since [[2003]]

In the typical [[paradigm]], a [[rat]] or [[mouse]] is placed into a small pool of [[opaque]] water—back-end first to avoid [[stress (medicine)|stress]], and facing the pool-side to avoid bias—which contains a escape platform hidden a few [[millimeter]]s below the water surface. Visual cues, such as colored shapes, are placed around the pool in plain sight of the animal.

Ryan was born in [[Niles, Ohio|Niles]] and graduated from John F. Kennedy High School in [[Warren, Ohio|Warren]]. He received a bachelor of arts degree from [[Bowling Green State University]] in 1995. In 2000, he earned a law degree from [[Franklin Pierce Law Center]] in [[Concord, New Hampshire]].

The pool is usually 4 to 6 feet in diameter and 2 feet deep. The pool could instead be half-filled with water at 1 foot deep. Some sidewall above the waterline prevents the rat from being distracted by lab activity. Mice are less cooperative in the water maze, but the bonus is that they are available as ‘knockout’ [[mutant]]s.

Ryan served on the staff of controversial congressman [[James Traficant|Jim Traficant]] (D-Ohio) in the mid-1990s. From [[2000]] to [[2002]], he served one term in the [[Ohio State Senate]].

When released, the rat swims around the pool in search of an exit while various [[parameter]]s are recorded, including the time spent in each [[quadrant]] of the pool, the time taken to reach the platform ([[Latency (engineering)|latency]]), and total distance traveled. The rat's escape from the water reinforces its desire to quickly find the platform, and on subsequent trials (with the platform in the same position) the rat is able to locate the platform more rapidly. This improvement in performance occurs because the rat has learned where the hidden platform is located relative to the conspicuous visual cues. If the rat does not escape within 1 to 2 minutes, it is rescued. After enough practice, a capable rat can swim directly from any release point to the platform. This ability is attributed to a spatial map in a [[brain]] area called the [[hippocampus]].

After Traficant was convicted on criminal charges in 2002, Ryan declared his candidacy for his mentor's seat. As the result of redistricting following the 2000 [[census]], the 17th, which had long been based in Youngstown, now included a portion of [[Akron]]. Previously, all of Akron had been part of the 14th District, represented by eight-term Democrat [[Thomas C. Sawyer|Tom Sawyer]]. However, the 14th had been eliminated in redistricting, and Sawyer's home was drawn into the 17th. In the 2002 Democratic primary, Ryan pulled off a surprise defeat of Sawyer, who was seen as insufficiently labor-friendly in the redrawn district. Traficant ran as an independent in the race.

== Pharmacological manipulation ==

Ryan easily won election in [[November]]. When he took office in [[January]] 2003, he was the youngest Democrat in the House. He was reelected with almost no opposition in [[2004]].

Various [[drug]]s can be applied to test subjects before, during, or after maze training, which can reveal information about spatial learning and its underlying mechanisms. For example rats treated with the [[NMDA receptor]] blocker [[APV]] perform poorly in the Morris water maze, suggesting that NMDA receptors play a vital role in spatial learning [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=1345945]. And since [[long-term potentiation]] -- a potential [[biology|biological]] mechanism for behavioral learning -- also requires NMDA receptors, spatial learning may require LTP.

Recently, before the [[U.S. presidential election, 2004|2004 presidential election]], Ryan spoke on the House floor in a charismatic speech denouncing the Bush administration's denial of a draft reinstatement, comparing this to the administration's previous claims that Iraq was developing weapons of mass destruction, the Bush tax cuts would create jobs, and other such claims. A video clip of this impassioned speech began to circulate throughout the Internet, particularly through left-wing media sites, and can be found here [http://homepage.mac.com/njenson/movies/timryanlow.html].

Liang et al reported in [[1994]] that spatial learning requires both [[NMDA receptor|NMDA]] and [[AMPA receptor]]s, consolidation requires NMDA receptors, and the retrieval of spatial memories requires AMPA receptors [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=7796636].

Ryan was strongly courted by national Democrats to run against [[Mike DeWine]] for Senate in [[2006]], but declined.

== Water maze vs. Conventional mazes ==

==See also==

* [[Election Results, U.S. Representative from Ohio, 17th District]]

* [[List of United States Representatives from Ohio]]

Watermaze has advantages over conventional mazes (e.g., [[plus maze]]). There are no [[local cue]]s such as [[scent trace]]s; no fixed escape-fomula; the rat makes good progress in the trials because it wants to escape. Rats are natural swimmers – they are not distressed but they do want to find that platform. Mice have an option to float, and maybe this is why they are not so cooperative in watermaze. It has been suggested that they don’t aim to find the platform, but trick the technician into rescuing them.

==External links==

*[http://timryan.house.gov/hor/oh17 Official site]

== Watermaze analysis ==

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{{succession box | before=[[Jim Traficant]] | title=[[List of United States Representatives from Ohio|U.S. Representative from Ohio's 17th Congressional District]] | years=2003- | after=Incumbent}}

The earliest and classic measure of learning is ''[[Latency (engineering)|latency]]'', which refers to the amount of time it takes to find the platform. However, rats can cheat. They might guess an area and swim a search pattern, getting to the platform quite quickly. There is a whole bunch of further analyses, which can tease out true spatial learning. The same swim is used, but a [[video tracker]] is required. Professional systems come with a suite of analysis features to extract measures such as time and path in [[quadrant]]s, near platform, in any specified area. The [[Gallagher measure]] looks for average distance to platform. The [[Whishaw corridor test]] measures time and path in a strip from swim-start to platform.

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Mice are smart

{{OH-FedRep}}

== Atlantis platform ==

A more advanced way to stop the rats cheating is the [[Atlantis rising platform]], which stays deep in the water and only rises when the rat lingers at the right place.

== References ==

* Davis S, Butcher SP, Morris RG. "The NMDA receptor antagonist D-2-amino-5-phosphonopentanoate (D-AP5) impairs spatial learning and LTP in vivo at intracerebral concentrations comparable to those that block LTP in vitro." ''J Neurosci''. 1992 Jan;12(1):21-34. PMID 1345945

* Liang KC, Hon W, Tyan YM, Liao WL. "Involvement of hippocampal NMDA and AMPA receptors in acquisition, formation and retrieval of spatial memory in the Morris water maze." ''Chin J Physiol.'' 1994;37(4):201-12. PMID 7796636

[[de:Morris-Wasserlabyrinth]]

==External links==

* [http://www.hvsimage.com/papers/index.htm Watermaze publications 1966-2002]

* [http://neco.mitpress.org/cgi/content/abstract/10/1/73 Information on the hippocampus]

* [http://www.mailtalk.ac.uk/archives/watermaze.html The UK Academic Watermaze Discussion Group]

[[Category:1973 births|Ryan, TimMazes]]

[[Category:U.S. Representatives from Ohio|Ryan, TimNeuroscience]]

[[Category:Irish-American_politicians|Ryan, Tim]]

[[Category:Irish-Italian-Americans|Ryan, Tim]]