Neurobiology of Memory Reconsolidation

Neurobiology of Memory Reconsolidation What is the current understanding of the neurobiology of memory reconsolidation and how will impact psychology. Abstract This essay is focusing on the neurobiology of memory reconsolidation, specifically on the molecular mechanisms of LTP and reconsolidation, and the crucial role synaptic plasticity plays in fear conditioning and its resultant implication for psychopathology specifically Posttraumatic stress disorder This essay is focusing on current understanding of the neurobiology of memory reconsolidation, specifically on the molecular mechanisms of LTP and reconsolidation, and its resultant implication for psychopathology specifically promising research using propranolol and d-cycloserine as a treatment of post-traumatic stress disorder. Memory consolidationis the process by which memories are stabilised after being acquired. Consolidation studies have traditionally focused on the hippocampus andsystems consolidation, whereshort term memories become long term memories and independent of thehippocampus over time (Pinel, 2011). The more recently discovered process of consolidation is synaptic consolidation, which occurs within the first few hours after learning, and requires protein synthesis and gene transcription (Pinel, 2011). Long term memories were once considered to be stable, but within the last decade, the discovery of reconsolidation, the process in which stored memories can be retrieved and held in labile short-term memory, has changed theory and research on memory (Pinel, 2011). The neurobiological process of synaptic memory consolidation is thought to be long-term potentiation (LTP), which is the prolonged strengthening of the synapse with increased signalling between two neurons (Sacktor, 2012). The model of LTP and synaptic consolidation, as first theorised by Hebb (Pinel, 2011), suggests that changes in membrane potential and alterations of synapticprotein synthesis such as activating Phosporylated Mitogen Activated Protein Kinase (MAPK),are achieved through activatingintracellular transduction cascades, such as glutamate activating the NMDA receptor so that calcium ions can enter the neuron. These molecular cascades triggertranscription factors such as CREBthat lead to changes ingene expression through RNA synthesis (Pinel, 2011). The result of the gene expression is the lasting structural remodelling of synapses. This complex process of the molecular cascade, expression and process of transcription factors, is susceptible to disruptions in the short ti me period immediately following memory induction (Nader, Schafe LeDoux, 2000a). The potential for memory to be distrupted during consolidation has been extensively researched using pharmacology and trauma. For example, in experiments on Pavlovian fear conditioning in rats, LTP and fear conditioning were blocked when NMDA-receptorantagonistswere administered (Nader et al, 2000b). This process ofLTPis regarded as a contributing factor tosynaptic plasticityand in the growth ofsynaptic strength, and is thought to underlie memory formation, as it affects memory when disrupted. It was previously thought that even though this long process of consolidation could be disrupted, once a memory was consolidated it could not be disrupted. This classic view has been revised over the last 15 years, with extensive research showing that consolidated memories, once retrieved, revert to a labile state where they can be disrupted and undergo another consolidation process, called reconsolidation. (Shwabe, 2014). Reconsolidation was first hypothesised after studies were done using electroconvulsive shock therapy to disrupt consolidated fear memory (Tronson Taylor, 2007). Nader’s (2000a) landmark research using Pavlovianfear conditioningon rats found that a consolidated fear memory can return to alabilestate, when the amygdalais infused with theprotein synthesis inhibitor anisomycin. Subsequent studies have also shown that post-retrieval treatment with protein synthesis inhibitors can lead to an amnestic state (Shwabe, 2014). It has been concluded therefore that cons olidated fear memory, when reactivated, enters a changeable state that requires de novo protein synthesisfor new consolidation or reconsolidation of the old memory (Shwabe, 2014). Since these breakthrough studies many more have found evidence supporting reconsolidation, and have explored its processes and implications. Reconsolidation research over the last decade has demonstrated that some, but not all memories can be strengthened, weakened, or updated thus providing an opportunity to modify some long term memories (Shwabe, 2014). This very limited essay will focus on a few of the important animal and human studies related to fear memory and reconsolidation theory and its implications for psychology. Fear conditioning, fear memory and extinction learning experiments, often use manipulations of theamygdala, due to its involvement in the encoding and memory of significant emotional experiences (Agren et al, 2012). Most of the research on reconsolidation has been done on animals, one of the first studies of human fear memory consolidation was by Kindt in 2009 in which healthy participants were first fear-conditioned and the fear was reactivated by a single presentation of a conditioned stimulus 24 hours later. Shortly before memory reactivation, participants received the beta-adrenergic receptor blocker propranolol during the proposed reconsolidation window, which resulted in substantial weakening of the behavioural fear response and the return of fear memory. Research by Schiller (2010) also explored fear memory activation and update mechanisms and extinction learning, and found the ventromedial prefrontal cortex (vmPFC) plays an important role (Schiller, 2013). Agren et al (2012) also demonstrated fear memory trace erasure in the amygdala of humans using behavioural manipulations. Using functional brain imaging, Agren and colleagues (2012) found that when reconsolidation was disrupted through extinction training, the fear memory was significantly weakened and the memory trace was erased in the amygdala. Additional important recent research providing support for memory updating used Pavlovian fear conditioning manipulations and micro density heat map measures of fear memory on the lateral amygdala of rats, and found that the memory recapitulated not only in the same location but in new areas during reconsolidation (Bergstrom, McDonald, Dey, Tang, Selwyn Johnson, 2013). These, and many more important studies using different experimental manipulations, suggest that memory is labile and updated after reactivation, and that more or less the same areas are recruited for reconsolidation that are involved in initial memory formation. The potential ability to modify established emotional memories through the processes of memory updating, reconsolidationand extinction of conditioned fear memories has important implications for the treatment of many mental disorders, including anxiety disorders, such as post-traumatic stress disorder. Posttraumatic stress disorder is classified as ananxiety disorderin the DSM iV, characteristic symptoms of PTSD are strong traumatic memories that are continuously retrieved in an intrusive manner, causing re-experiencing of the original trauma (Schwabe, 2014).Research is focusing on testing pharmacological treatments and behavioural interventions that target memory reconsolidation in PTSD populations. One drug being researched in neurobiology for the treatment of PTSD is propranolol, the b-adrenergic receptor antagonist that has effects on protein synthesis. The idea that propranolol could be a useful treatment in PTSD stemmed from studies showing that this drug can disrupt the reconsolidation of fear conditioning in animal models and humans (Kindt, 2009). There is some evidence of success with propranolol, such as in pilot studies by Pitman (2002) and Vaiva (2003) which found that immediate treatment with propranolol decreases posttraumatic stress disorder two months after trauma. In recent experiments using propranolol, patients with chronic PTSD were asked to prepare a written script of their personal traumatic experience that caused the PTSD. Each patient then received either propranolol or a placebo (Brunet et al, 2008). One week later, all patients underwent a procedure where there physiological arousal was tested as the script was read. The results showed that psychophysiological responding was significantly lower in patients who had received propranolol a week earlier than in patients who were administered a placebo. These findings were replicated and extended in three open-label studies where PTSD symptoms were significantly lower than at pretreatment (Brunet et al, 2011). In these promising studies on the effect of post-retrieval propranolol in chronic PTSD it is ambiguous as to whether the benefits were from propranolol enhancement or the psychological intervention; And whether propranolol enhanced extinction consolidation or blocked memory reconsoli dation. (de Kleine et al, 2013). Some of these studies also lacked the appropriate control groups that would be required to conclude that the observed effects are due to changes in memory reconsolidation, however, these findings suggest that postretrieval manipulations with propranolol might be a promising tool in the treatment of PTSD, even when the trauma is decades old. d-cycloserine (DCS) is another pharmacological intervention being recently researched in reconsolidation and PTSD due to it being a partial NMDA receptor agonist and extinction enhancer (De Kliene, 2014). Research on using exposure therapy with DCS for PTSD suggests that it could be promising (De Kliene, 2014). Exposure therapy is established as an effective form of fear extinction training in PTSD through the repeated exposure of the trauma memory, and its emotional processing (De Kliene, 2014). De Kleine, Hendriks, Kusters, Broekman, and van Minnen (2012) investigated the effect of DCS on exposure therapy on a female civilian population and found no overall enhancement effects, but a stronger treatment response. However, a second study on a male veteran population found a significant enhancement (Litz et al, 2012). Some criticisms of these studies were the possibility that DCS might have undesirable effects when there is no in session fear extinction, and the need for more research and better administration of the drug (De Kleine, 2014). Sheeringa (2014) researched the effect of d-cycloserine with cognitive behaviour therapy on pediatric posttraumatic stress using a randomized placebo-controlled d-cycloserine. So far, DCS has only shown as extinction effect when used with behavioural training such as exposure therapy and CBT. This study did not show a greater effect on reducing PTSD symptoms, but did show preliminary evidence for improving attention of participants. Another promising study currently in press looked at whether DCS enhanced psychotherapy when used with virtual reality trauma exposure therapy (Difede, 2014). The pilot trial was randomized, placebo-controlled, and double-blind and found significantly greater PTSD remission rates for DCS group, with larger between groups effect sizes (Difede, 2014). Understanding the processes of reconsolidation and the crucial role synaptic plasticity plays in fear conditioning does have exciting and important implication for psychopathology specifically PTSD. There are still barriers and boundary conditions to be understood and overcome for example, memory age and strength. In Posttraumatic stress disorder, unwanted memories need to be retrieved and destabilized before they can be modified during reconsolidation. One of the barriers particular to PTSD is that researchers have proposed that younger and weaker memories are more likely to be modified after reconsolidation than older and stronger memories which are less likely to be modified (Wihchet, 2011). Further boundary conditions highlighted by Shwabe at al (2014) is the context in which the reactivation takes place, and the presence of new information at reactivation of the memories. Therefore, more research is needed to understand exactly when memories do and do not undergo reconsolidation in order to use reconsolidation as a treatment for disorders such as PTSD.

Cold environments Case Study- Alaska Essay

Location * State in the United States-international boundary with Canada to the east, arctic ocean to the north * Largest state in United States by area, however least densely populated Economy * GDP in 2007: $64,333 * Per capita personal income : $40,042, rank :15th in nation * Oil and gas industry dominates the Alaskan economy * More than 80% of states revenues derived from petroleum extraction * Main export : seafood , agriculture represent only fraction of economy * Largest employers: * Providence health and services : 4000+ av. Monthly employment in 2010 * Walmart: 3000-3259 av .monthly employment 2010 History * First oil claims in Alaska made in the 1890, noted oil sea pages on iniskin bay and cold bay- not pursued by Russians * 1898- first Alaskan wells drilled in Iniskin Peninsula * Alaska’s first productive oil drilling operation was at Katalla, on the Gulf of Alaska, south of the Copper River delta * In 1911 several new wells in the district began to produce significant oil, costs not big enough to justify extraction * In 1960, following the statehood of Alaska and the creation of the state natural resources agencies, oil companies bought exploration leases for work in Cook Inlet * The boom in economic development and population growth after the discovery of oil was immediate and still continues Types of Development in Alaska * Oil and Gas industry- major oil fields developed along central north slope * Oil production accounts for 93% of Alaska’s unrestricted general fund revenues. * Since statehood, Alaska has received $164 billion in revenues from oil * Development in the fishing industry- sea provides endless harvest worth billions of pounds. Over 3 million lakes, 3000 rivers and 34 000 miles coastline- bountiful fishing regions in the world * Salmon fishing industry- worth $11 billion a year * Provide thousands of jobs, long term economic engine * Pollock fishery- 1,252,000 million metric tons- 2.7 billion ponds annum * Seafood- top export commodity. 2009- 1.6 b dollars. Accounted for 50% states total exports. * Seafood processing accounts 71% of manufacturing jobs in ALK. * Fishing industry- generated 54 000 jobs- short seasonal * Mining- historically a cornerstone of alaska’s economy. Today, mining industry brings broad range of benefits- offering highest paid jobs in the state. * Produces zinc, lead, copper , gold, silver, coal * Alaska’s 7 largest mines Provided more than 2,250 full time jobs of 9500 total mining ind jobs in state * Mining creates public revenue by paying state and local taxes * Help support local economies in both urban and rural Alaska. * Issues: spent $300 million on exploration last year * drilling costs and fuel expenses have risen sharply * Facts and economic impact-cumulative value of mining industry: $4.4 bil. 2011 * Minerals are the states second largest export commodity. Accounted for 31% of states export total- zinc and lead from Red Dog mine * Approximately 200 placer mines produced 70,000 ounces of gold, as well as platinum, in Alaska in 2011. In addition to Alaska’s active precious-metals mining industry, there were more than 120 active rock quarries, and sand and gravel operations throughout the state. Pressures on Cold Environment * Alaska is unique state- economic development in it’s remote, petroleum based economy- resembles oil rich developing nations than other US states * Realtively small size of the Alaskan economy can discourage production for local use. * Geography wise- their location is at a disadvantage. Difficult to transport oil to other countries * Trans Alaska pipeline * Pipeline flows through natural biomes, upsets animal trails, carries potential of a devastating leak * Woodland destroyed- also people’s homes affected

Sex’ vs ‘Sexuality

Assembling an Understanding of ‘Sex’ Verses ‘Sexuality’ â€Å"Biologists and psychologists who have accepted the doctrine that the only natural function of sex is reproduction have simply ignored the existence of sexual activity which is not reproductive† Alfred Kinsey (The Invention of Sexuality 40) The terms ‘sex’ and ‘sexuality’ have not always had a clear differentiation, but as the study of sexuality (sexology) has continued and become more commonly studied and recognized, these terms have adapted their own definitions.However, each does not have a perfect definition, because people will have their own opinions regarding the terms. The above quote by a historian of sex was interesting to me because it brings up the aspect of biology within the understanding of the terms ‘sex’ and ‘sexuality’. My personal idea, or understanding, is that ‘sex’ constitutes the more biological side†” ones physical features, gender, reproduction (‘sex’ is also the abbreviation for sexual intercourse); and the term ‘sexuality’ makes up everything else that surrounds an individual’s definition of their sexual identity, orientation, and feelings.When reading articles online, I came across this quote: â€Å"sexuality is about who or what you are attracted to, not where you put your dick† (bitheway), which I found to be a very blunt but interesting way to think about what constitutes ‘sexuality’. â€Å"Where you put your †¦Ã¢â‚¬  is your personal preference, but that preference is a compilation of the aspects of one’s personal world and how they have come to define and understand their individual inclination. All of the parts that are compiled in order to form ones individual definition are aspects of ‘sexuality’ within our culture.Another page online gives definitions for ‘sex’ and Ã¢â‚¬Ë œsexuality’ that I have found to be the most clear and complete: Sex refers to whether or not a person is male or female, whether a person has a penis or vagina. Sexuality refers to the total expression of who you are as a human being, your femaleness or your maleness†¦ Your sexuality is an interplay between body image, gender identity, gender role, sexual orientation, eroticism, genitals, intimacy, relationships, and love and affection†¦ includes his or her attitudes, values, knowledge and behaviors.How people express their sexuality is influenced by their families, culture, society, faith and beliefs. (Sex and Sexuality: Understanding the Differences) The influence from all aspects of our lives that guide us to define our sexuality is a major component in sexology. The italicized words in the definition above are some I think are very significant in understanding what constitutes ‘sexuality’.Since the study of sex started to dramatically change, there has been more understanding within so many topics of sexuality, such as gender (roles and variance), marriage and the family, homosexuality, heterosexuality, bisexuality, intersex, trans-gender/sex/vestite, evolution of sexual identities, legal and medical regulation, religious roles/codes, phallocentricism, women’s bodies and health, illegitimacy, â€Å"and the importance of social networks and oppositional sexualities† (The Invention of Sexuality 39).This is only the first week that I have studied sexuality and culture in an educational environment, and after enjoying many sources of new material I have begun to compile my own understanding of ‘sex’ and ‘sexuality’, which is just the beginning of my learning on the subject. One of the most important aspects to take away from these introductory lessons is how grand of a role society and culture have on sexuality.It is so important to be aware of and take into account culture’s influen ce on sexuality now and within the history of sex. In our US society (and this is a generalization) some vital influences are class, race/ethnicity, gender, age, family history and how one was raised, physical ability, religion and region. Now that I have collected a better understanding of ‘sex’ and ‘sexuality’ as educational terms, I can further my knowledge of everything that makes up sexuality within cultures around the world.Bitheway. Sex Verses Sexuality. Bi The Way: An exploration of Male Bisexuality. 6 May 2008. http://www. bitheway. co. uk/2008/05/06/sex-versus-sexuality/. Sex and Sexuality: Understanding the Differences (Learning Activity). RECAPP 2007-2009. http://www. etr. org/recapp/index. cfm? fuseaction=pages. LearningActivitiesDeta il&PageID=167 The Invention of Sexuality. Sexual Lives: A Reader on the Theories and Realities of Human Sexualities. McGraw-Hill, 2003.

buy custom Impacts of Computers essay

buy custom Impacts of Computers essay We owe everything that we have today to technology. Technology has greatly impacted our lives. However, computer technology has completely outdone all the other forms of technologies. Computers have made the impossible possible, things that could not easily be achieved are now possible due to them. The history of computers goes back a long way. The first electronic computers were people. This is because the machines developed did things that were initially carried out by people. Originally, the term computer was a title assigned to human beings whose role was to carry out repetitive computation of calculations (Cnaan and Parsole, 2009). The abacus was invented to aid mans memory while carrying out calculations. In 1942, John Eckert, John Maunchly and their associates built the first electronic computer. It is undeniable that computers have made such a big impact in our lives and the society as a whole. It is no longer possible to find a place where computers are not involved in carrying out one or more activities. Whichever direction you turn into, there is always the need of a computer. Currently almost all business entities need computers and their respective technologies to carry out their activities. The past few years have seen this field of technology advance rapidly and due to this it has been transformed as the core tool in business today (Cnaan nd Parsole, 2009). Computer technology has seen unimaginable advancements prompting every organization to use it. Investors consider computers inexpensive assets that are a must have due to their conveniences in creating opportunities for investment. It is through computers that we are able to search for jobs online, learn a vast range of things, carry out research and buy stock. It is true to assert that computers have transformed the world a lot (Rosenberg, 2004). It is through the computer that man has been assisted to step forward and face the future. We owe a lot to computers. Thorough computers, space exploration is possible, new vehicle designs have been developed, entertainment is more interesting and science and medicine has been able to manufacture better and improved medicines to cure diseases. Though to some it may be difficult to notice how computers have impacted our lives, it is due to computers that life has become much easier and enjoyable. As stated by Rosenberg (2004), computers play a very vital and positive role in the education sector. Students are able to work on their assignments through internet research. Learners can also type their reports on the word processing program. This is a program thatt makes it possible for learners to type their work or assignments. Business entities and computers are inseparable. The entities use computers to keep track of their stocks, money, accounts and all things that are crucial for the running of the business. Computers have various programs which are important in presentation of information and ideas to people. The computer is not only essential for its word processing program but the device can carry a huge sum of data and information. Thinking that our past generation was able to live without computers is unbelievable. The uses of computers range from one thing to millions of activities. Commerce is unheard of and impossible without computers (Rosenberg, 2004). Computers regulate commercial activities and communicate to millions of people across all over the world in a matter of seconds concurrently. Computers have helped the world a lot and thus preparing for the future more comfortably. Entertainment and businesses entities use computers to make profits, education institutions use computers to assist learners to learn better. Similarly, the medical department cannot look down upon the importance of computers. Without the assistance of computers, many things that are possible today would not have been possible. The world would have been a primitive and dull place to live in without this important device. Buy custom Impacts of Computers essay

Mans Fate Book Report essays

Man's Fate Book Report essays Andr Malraux was a French writer, explorer and statesman, who was born in Paris on 3 November 1901. He was self-taught through his love of books and paintings and his early acquaintance with avant-garde poets and artist. (Winegarten 268) He learned Oriental languages that came in handy during his time in Asia. Where he became extremely critical of the French colonial authorities in Indochina, helping to organize the Young Annam League and founded the newspaper Indochina in Chains. On his return to France he published his first novel, The Temptation of the West (1926). This was trailed by The Conquerors (1928), The Royal Way (1930) and Mans Fate (French: La Condition Humaine) (1934), an influential novel about the overcome of a collective government in Shangai and the options the losers have to face. He used his experiences in Asia as background for his first novels, counting Mans Fate (1933), which won the Prix Goncourt [of literature]. (Bertram 53) Malrauxs career begins in mystery with the expedition to Indochina, the obscure affair of the missing statues, a short term of imprisonment, and a plunge into Eastern politics. The details of these matters are still unknown to us, but it is their resonance that counts. With all their shadow and uncertainty they nevertheless suggest a purity of adventure. Malraux entered the European consciousness not as a writer but as an event, as a symbolic figure somehow combining the magical qualities of youth and heroism with a sense of unlimited promise. (William Righter in The Rhetorical Hero, 1964) kirjasto.sci.fi/malraux.htm Mans Fate was first published in the year 1933, as a fictional story of the early days of the Chinese Revolution. This novel remains an n influential term of psychological insight into the strength of political revolution. From the opening scene, in which Chinese terrorist Chen Ta...

SWOT Analysis for McDonalds Essay Example | Topics and Well Written Essays - 1500 words

SWOT Analysis for McDonalds - Essay Example The role of SWOT analysis is to take the information from the environmental analysis and separate it into internal issues (strengths and weaknesses) and external issues (opportunities and threats).† The purpose of this paper is to perform a SWOT analysis on McDonald’s. In the process of this analysis, the objectives it pursues; the methods by which it has grown in size and the reasons the company might have had for choosing those methods; and the political, economic, socio-cultural, and technological (PEST) factors which are shaping the external environment in which the company is operating will be thoroughly examined. McDonald’s names their vision statement as, â€Å"We envision a supply system that profitably yields high-quality, safe food products without supply interruption while creating a net benefit for employees, their communities, biodiversity, and the environment† (McDonald’s, 2008, pg. 1). The company holds a number of principles as well, claiming, â€Å"Our work toward a socially responsible supply system is motivated by our commitment to our customers, leadership on sustainability issues, and our desire to ‘do the right thing’† (McDonald’s, 2008, pg. 1). First of all, they pledge to find solutions to how their supply chain is affected by both the natural and social worlds through the utilization of a systems-based approach. Second, when they plan their objectives, they set their sights on long-term goals. Third, from a globally operational standpoint, they pledge to focus on the local needs of the area in which a particular restaurant or chain of restaurants is operating. Fourth, they strive to use the best science possible upon which to base their strategies. Fifth, they work to continuously improve through building positive relationships with their suppliers.  

The European Sovereign Debt Crisis Research Paper - 1

The European Sovereign Debt Crisis - Research Paper Example After a while, the deficit rate became enormous, thus leading to the rise of the sovereign debt crisis in the year 2009. Therefore, it is arguable to state that is the starting point of the European debt crisis. This paper will attempt to look at the causes and effects of the European debt crisis. How Greece became the origin and what other countries were affected by the situation. Finally, the current state of Europe after the debt crisis shall be analyzed. Greece had one of the fast growing economies and as a result had a massive deficit. As the global financial crisis came to pass, Greece was greatly affected. This was evident especially on the country’s largest industries (tourism and shipping industry). This led to lump sum spending to keep the economy going, but instead the sovereign debt increased with each passing day. With increased borrowing from the International Monetary Fund and the European Union, the Greek government was problem bound. Greece registered a debt of five hundred and forty billion dollars (Stein, 1). This is one hundred and twenty five percent of its Gross Domestic Product. Despite Greece making one or two mistakes, there were other factors that led to the crisis in Greece. External debts of Europeans states are at the center of the recent crises. In general, the debt crisis is associated with the budget deficits being in excess of the values provided by the Maastricht Treaty, and the Stability and Gro wth Pact (Ludwig Von Mises Institute, 1). These groups only focused on debt and deficit ratio ignoring external debts. Consequently, the laws governing the European Central Bank do not allow single investors and creditors to borrow government bonds in case of a crisis. Eventually, the debt crisis became alarming as the country decreased public benefits (Greece froze civil service salaries and in turn raised taxes and retirement