he nervous system is the body’s speedy, electrochemical communication system. It consists of all the nerve cells of the peripheral and central nervous systems.
The central nervous system consists of the brain and spinal cord. The peripheral nervous system is the sensory and motor neurons that connect the central nervous system to the rest of the body. Nerves are the neural cables of the nervous system containing many axons. They are part of the peripheral nervous system. They are connected to the central nervous system by muscles, glands, and sense organs.
Sensory neurons carry incoming information from the sense receptors to the central nervous system. Interneurons are part of the central nervous system. They internally communicate and intervene between the sensory inputs and motor inputs. They are the most common type of neuron. Motor neurons carry outgoing information from the central nervous system to the muscles and glands.
– The Peripheral Nervous System –
The peripheral nervous system is made up of the somatic nervous system and the autonomic nervous system. The somatic nervous system controls the body’s skeletal muscles. The autonomic nervous controls the glands and muscles of the internal organs. It is broken down into the sympathetic and the parasympathetic nervous system. The sympathetic nervous system arouse the body, mobilising its energy in stressful situations (fight or flight response). The parasympathetic nervous system calms the body, conserving its energy.
– The Central Nervous System –
The spinal cord is the information highway connecting the peripheral nervous system to the brain. Ascending neural tracts send up sensory information. Descending neural tracts send down motor control information. Reflexes are the body’s autonomic response to stimuli controlled by the spinal cord. They are composed of 1 sensory neuron and 1 motor neuron that communicate through one interneuron. Because they only run through your spinal cord, they react automatically without your brain being involved in the process. The spine sends information back to the brain. Bodily pain or pleasure is controlled by the brain.
The brain receives information, interprets it and then decides on a response. It functions like a computer, receiving slightly differing images of an object from the eyes, it computes the differences and infers how far the object must be to project such a difference.
Neural networks are interconnected neural cells which, with experience, can learn, as feedback strengthens or inhibits connections that produce certain results. Stephen Kosslyn and Oliver Koening proposed to think of neural networks as networks of people. Neuron network with nearby neurons with which the can have short, fast connections. Each layer of a neural connects with various cells in the next layer. Learning occurs as feedback strengthens connections that produce certain results. New computer models simulate this process plus the excitatory and inhibitory conniptions to mimic the brain’s capacity for learning.
Philip G. Zimbardo is world renowned for his controversial study, the Stanford Prison experiment. In more recent years he has become known for his theory known as the “Lucifer Effect,” in which he investigates the question “What makes good people do bad things?” A Professor Emeritus of Psychology at Stanford University and currently still teaching, Zimbardo also holds the title of two-time past president of the Western Psychological Association and past president of the American Psychological Association. As a social psychologist, Zimbardo constantly questions how we interact and influence others in our society; however, most notably, he seeks to discover how our environment is and will remain our strongest influence.
Philip Zimbardo was born in 1933 to a Sicilian-American family in New York City, New York. His academic career landed him classmates with another future social psychologist, Stanley Milgram, in James Monroe High School. Next he merited a BA from Brooklyn College and a PhD from Yale University. After several years of teaching a universities all across the United States, he finally started his professorship at Stanford in 1968. Since 2000, Zimbardo has been on a mission to bring psychology to the forefront of research and also the public eye by presenting a TV series on “discovering psychology” and lecturing at TED, to name a few.
Inspired by Stanley Milgram’s obedience studies in 1963 that demonstrated the moral aberration people are willing to commit to obey authority, Zimbardo aimed to discover what makes people concede their moral compass when put in a place of power. Zimbardo wanted to uncover under what circumstances people would “willing use (or abuse) power granted to them.” In light of this curiosity, he carried out the Stanford Prison experiment in 1971. His subjects were twenty-four, mentally healthy, American, university students. The similarity of subjects attempted to control for all dependent variables. Randomly, the students were assigned the role of “guard or prisoner.” Then one morning the “prisoners” were arrested by real police officers whom booked to them be transferred to the mock prison built in the basement of the Stanford Psychology Department.
Once transferred into the “prison,” the “prisoners” were “stripped, searched, deloused, and given uniforms and bedding.” The prisoners were then stripped of their identify and dehumanised by the “guards” who were told to refer to them by assigned numbers. To heighten their lack of freedom, the “prisoners” also had a chain bolted around one ankle. The “guards” wore military inspired uniforms, sunglasses (to prevent eye-contact) in addition to carrying keys, whistles, handcuffs and clubs. The “guards” patrolled 24 hours a day and where given full control of the “prisoners” to maintain order. It did not take long for the environment to quickly turn “threatening” forcing the experiment to end prematurely after only six days.
Every single “guard” became “abusive and authoritarian; prisoners were denied food or bedding, hooded, chained, and made to clean toilet bowls with their hands.” The “prisoners” were used as playthings to take part in the “guards” degrading games. One prisoner had to be released after only thirty-six hours after suffering a nervous break.
Zimbardo’s findings, the basis for the Lucifer Effect showed the world that good people can be induced to evil by “immersion” in “total situations.” Total situations have an “apparently legitimizing ideology and approved rules and roles.” Zimbardo served as an expert witness in the defense of a guard during the Abu Ghraib trails, which as Zimbardo discusses in his TED video, showed many parallels with the Stanford Prison Experiment. The Abu Ghraib prison abuse against Iraqi prisoners by American soliders gathered wide controversy. Please view the TED video for further information. The scary thing Zimbardo explains is that “any deed that any human being has even done, however horrible, is possible for any of us to do – under the right or wrong situational pressures.” However, as Zimbardo discusses in his final chapter of The Lucifier Effect, his book, these situational pressures not only shows human capacity for evil but also for heroism.
Collin, Catherine. The Psychology Book. New York: DK Pub., 2012. Print.
“Philip G. Zimbardo.” Philip G. Zimbardo. N.p., n.d. Web. 09 Aug. 2012. <http://www.zimbardo.com/>.
Zimbardo, Philip G. The Lucifer Effect: Understanding How Good People Turn Evil. New York: Random House, 2007. Print.
Born in Bramen, Germany in 1850, Ebbinghaus was the first psychologist to study learning and memory by conducting experiments on himself. At age seventeen, he commenced his study of philosophy at Bonn University on the eve of the Franco-Prussian War. After completing his studies, he travelled to France and England, conducting research on the “power of memory.” In 1885, he published Memory “detailing the nonsense syllable” research. The nonsense syllable, logatome or pseudoword is a string of syllables that resembles a real word is in fact “nonsense.” In the psychology of learning nonsense syllables are used as a way to examine speech recognition. After becoming professor at Berlin University, he established two psychological laboratories there. Finally, he moved to Berslau University, founded another laboratory, teaching there until his death in 1909.
Inspired by philosophers by the likes of John Locke and David Hume, Ebbinghaus argued that “remembering involves association,” linking things or ideas by similarities such as “time, place, cause or effect.” The goal of his research was to test how association can improve memory. To verify the accuracy of his findings, he recorded the results mathematically to see if “memory follows verifiable patterns.” This would become known as the Forgetting Curve.
To start his memory experiments, Ebbinghaus began by memorising lists of words to test his recall abilities. He then created 2,3000 nonsense syllables, three letters each with the same pattern consonant-vowel-consonant, to prevent association. He then grouped these nonsense syllables into lists, looked over the list for a few seconds, waited fifteen seconds to then try a second time. He then repeated his process until he could correctly recite the series. Alternating the list lengths and learning intervals, Ebbinghaus also tested how these variables effected the speed of learning and forgetting.
Ebbinghaus discovered that material he found meaningful, such as a poem, was up to ten times more easily remembered than the nonsense syllables. He also found that more time he spent memorising the list, the easier it was and the less time it took to reproduce the list from memory. In addition, he found that the information remembered after the first repetitions, were the most effectively remembered after time had passed. Finally, Ebbinghaus also found that typically, a very rapid loss of recall occurs in the first hour, followed by lowered rate of recall loss. To clarify, after nine hours sixty percent is forgotten and after twenty four hours, two-thirds of recall is lost. Plotted on a mathematical graph, Ebbinghaus’s findings shows a clear “forgetting curve” starting with a “sharp drop, followed by a shallow slope.”
Ebbinghaus’ findings still remain the basis of the psychology of learning and memory.
Collin, Catherine. The Psychology Book. New York: DK Pub., 2012. Print.
The brain enables the mind: seeing, hearing, remembering, thinking, feeling, speaking and dreaming.
Science now enables us to know about the living brain through lesions. Lesions are destroyed tissue. A brain lesion is naturally or experimentally caused destruction of brain tissue, which selectively removes tiny clusters of normal or defective brain cells without harming the surroundings. We can also probe the brain with tiny electrical pulses. Scientists can look upon on the messages of individual neurons and on mass action of billions of neurons. We can see colour representations of the brain’s energy – their consuming activity. These tools facilitated the neuroscience revolution.
The oldest method of studying the brain-mind connection is to observe the effects of brain disease and injuries. This has been going on for more than five thousand years. In the past two centuries, physicians have been recording the results of damage to specific brain areas. Some noticed that damage to one side of the brain often caused numbness or paralysis on the opposite side of body. This suggested that that somehow the right side of the body is wires to the left side and vice versa.
Other scientists noticed that damage of the back of brain disrupted vision and that damage to the left front part of the brain caused speech difficulties. These discoveries have helped scientists map the brain. Today scientists are able to electrically, chemically or magnetically stimulate various parts of the brain to record the effects. Modern electrodes are so small that they can detect the electro pulse in a single neuron.
An electroencephalogram or EEG is an amplified recording of the waves of electrical activity that travels across the brain’s surface. These waves are measured by electrodes placed on the scalp when presented with a stimulus.
A positron emission tomography or PET scan is a visual display of brain activity. It detects where a radioactive form of glucose travels to whists the brain performs a given task.
A magnetic resonance imaging system or an MRI is a technique that uses magnetic fields and radio waves to produce computer generated images that distinguish among different types of soft tissue. It also allows us to see structures within in the brain. MRIs align the spinning atoms in our brain through the use of a magnetic field as well as causing a pulse of radio waves that disorients them momentarily. When the atoms return to normal spin the release detectable signals. MRIs can also detect oxygen-laden blood flow.
Myers, David G. Psychology . 6. Worth Publishers, 2001., David G. Psychology . 6. Worth Publishers,2001. Print.
Some of you may have seen the crime-procedural drama “Lie to Me.” It ran on FOX between 2009-2011 until it got cancelled. The show stared Tim Roth as Cal Lightman, who along with his colleagues of the Lightman Group were consultants for the police and FBI. The Lightman Group specialised in applied psychology, specifically interpreting mirco-expressions and body language. What many people may not know; however, is that the techniques utilised by the Lightman Group in “Lie to Me” are based on the work of psychologist Paul Ekman.
Ekman was born in Newark, New Jersey in 1934 but after the outbreak of World War II, moved across the country. At a mere fifteen, Ekman joined the University of Chicago where he became interested in “Freud and psychotherapy.” This inspired him to apply to Adelphi University where he earned his doctorate in clinical psychology. After a stunt working for the US Army, he went on to join the University of San Francisco where he began research into “nonverbal behaviour and facial expressions.” This work lead to further studies on the “concealment of emotions in facial expressions.” Being appointed to professor of psychology at UCSF in 1972, Ekman stayed there until his retirement in 2004.
Emotions play a huge role in emotional disorders and psychotherapy; however, when Ekman began his studies in the 70s, the subfield was practically unexplored. In the early days of psychotherapy emotions were seen as symptoms rather than “something to examined in their own right.” Ekman was one the first psychologists to realise that emotions are as much a vital part in psychotherapy as processes, drives and behaviour. He came to realise the importance of emotions through his work with nonverbal behaviour and facial expressions.
Before Ekman’s experiments it was believed that physical expression of emotions were learnt according to a set of social conventions, implying that how we express ourselves differes from culture to culture. However, through his travels across the globe, photographing people – ranging from developed countries to untouched tribes in the Amazon – he found that even the tribespeople, untouched by media and the outside world, could interpret emotions through facial expressions as well as people in developed countries. This suggests that physical expression of emotions are universal and a product of evolution not social conventions. A post in the Immersion Blog makes a great point regarding Ekman’s credibility, which has been disputed by critics claiming that facial expressions are for communications purposes only and not subconsciously reflecting our internal life. Robbie Cooper, the blogger, refutes this claim arguing that
“We only think about expression when we want to use our body for communication on a conscious level. And a lot of the time we aren’t very good at faking internal states. If someone is playing a role in a social situation, it’s often expected of them, but much of the time we aren’t fooled by the performance. Which I think is one of the reasons why great actors are fascinating.”
Ekman put forth six basic emotions – surprise, anger, happiness, fear, sadness and disgust – and decided because of their ubiquitous nature, these six basic emotions must be quintessential to our psychological make-up. He noted that specific facial expressions relate to each one of these six basic emotions and must in turn be involuntary emotional responses. Furthermore, these responses occur before the mind has time to register the cause and can thus be read to reveal our internal state. Ekman’s research became the basis of his F.A.C.E. training programme aimed to familiarise people, specifically officers of the law and security professionals dealing with deception on a daily basis, with “microexpressions.” Microexpression is term coined by Ekman as the involuntary emotional response, reflected in our facial expression before our brain has time to process the cause.
In Ekman’s 2003 book, Emotions Revealed, he states that emotions can be far more powerful than any of the drives listed by Freud such as sex, hunger and the will for life. These revelations are revolutionary as they completely altered the way in which emotions were seen to play a role in psychological disorders. For example, unhappiness can override the will to live and fear and shame, a biproduct of trauma, can override sexual drive.
Cooper, Robbie. “Ekman Emotion Recognition Test.” Web log post. Immersion Blog. N.p., 29 June 2009. Web. 21 Aug. 2012. <http://blog.robbiecooper.org/2009/06/29/ekman-emotion-recognition-test/>.
Myers, David G. Psychology . 6. Worth Publishers, 2001., David G. Psychology . 6. Worth Publishers,2001. Print.
Born in a small village in Switzerland in 1875, Carl Gustav Jung grew up in a rather eccentric family. He became an excellent linguist at an early age and in 1903 married Emma Rausenbach, an intelligent young woman from a wealthy Swiss-German family. Emma later became a prominent psychoanalyst herself known as Emma Jung. Although originally educated as a psychiatrist, Jung’s meeting with Sigmund Freud in 1907, pushed him towards psychoanalysis setting him on the path towards becoming Freud’s protege. However, the pair became estranged as their theories diverged causing a permanent rift. Following World War I, Jung travelled across the globe studying native people, taking part in “anthropological and archaeological expeditions.” In 1935, Jung became professor at the University of Zurich before deciding to concentrate strictly on research.
Freud first introduced the idea that humans are guided by forces within ourselves, specifically our unconscious. He claimed that our experience of the world is directly affected by “primal drives contained in the unconscious.” Jung expanded on this basic philosophy inquiring into the basic elements that “make up the unconscious and its workings.” He was most intrigued by striking similarities between societies around the world despite completely differing cultures. In particular, the similarities found in myths and symbols ranging across cultures. Jung believed this could be explained by “something larger than the individual experience of man.”
To Jung it appeared that the existing commonality between these myths and symbols proved the existence of a “collective memory” passed down by generations as part of our heredity. He believed that this collective memory was housed in a part of the psyche and contained ideas “held in a timeless structure.” Finally, he proposed a notion that a distinct part of the unconscious is completely void of individual experiences, coining the term “collective unconscious.” Together with the ego, our conscious mind; the personal unconscious, our individual suppressed memories, the collective unconscious forms the three components of the psyche. We then inherit these collective memories found in the collective unconscious, allowing them to emerge within our own psyche creating symbols known as archetypes. Differing cultures, allow for layers and variations of these archetypes to exist simultaneously and just like with the evolution of all species on this planet, the layers of these archetypes reveal traces of the entire human experience.
Finally, our inherited archetypes, etched deep within our unconscious, serve as templates used by our psyche to “organise and understand our own experience.” Basically, archetypes serve as a guidebook programmed within our minds to help us make sense of the world as well as to survive it. Archetypes serve as the foundational structure on which our experience builds. They can be seen as emotions or behavioural patterns; regardless, they help us determine “a particular set of…expressions as a unified pattern that has meaning” seemingly instinctually.
Furthermore, Jung also is renowned in the world of psychology for his exploration of word association and his concepts of introversion and extroversion. His concepts inspired many well-known personality tests used today such as Myer-Briggs Type Indicator.
If you are interested in Jung you should consider checking out the movie A Dangerous Method. Also click here to see photos of my recent trip to the Jung Institute in Zurich.
Collin, Catherine. The Psychology Book. New York: DK Pub., 2012. Print.
Huntington Disease is a rare genetic condition that most people have never even heard of unless a) they study it b) they personally know someone with the disease or c) they are a fan of House. Luckily for me only a) and c) apply in this situation. However, I believe Huntington’s like a variety of other diseases is something the public needs to be educated about because awareness really is the greatest way to inspire research into any field.
As autosomal dominant disorder this makes Huntington’s especially dangerous because as a dominant trait a person only needs one affected allele to develop the disorder. Were the trait recessive such as the trait for hemophaelia, for example, then the likelihood of having Huntington’s is significantly lowered. When a trait is autosomal this means that it is no carried by any of the sex chromosomes (X or Y), rather is carried by any of the other 22 chromosomes the human body has. In Huntington’s the gene affected is located on chromosome 4, specially on the p (upper, shorter) arm.
The symptoms of Huntington’s has already been discussed on a previous post on basal ganglia disorders; however, in summation it results in damage to the striatum and cerebral cortex causing changes in personality including mood swings, involuntary movements known as hypokinesia and eventually dementia. As is common with most genetic disorders, the symptoms do not appear until adulthood. In Huntington’s the symptoms usually arise around mid-age, but unfortunately it can arise earlier than our 30s or 40s if unlucky. Once symptoms start appearing the person usually has about another 5 to 15 years until death. The age at which symptoms appear directly correlates with the genetics behind the abnormal gene.
Huntington’s is part of numerous diseases including varies ataxias and fragile X syndrome that result due to trinucleotide repeat. Specifically, Huntington’s is due to a repeat of the CAG trinucleotide. Normal alleles carry about 10 to 35 copies, but those suffering from Huntington’s and various other neurodegenerative diseases have more than 40 repeats. People with around 60 repeats with develop Huntington’s around the age of 20. These repeats in CAG result in the production of a “mutant protein” that eventually fill the striatum and cerebral cortex causing degeneration and ultimately death of these brain cells. In healthy individuals the gene involved in Huntington’s encodes for a large protein known as huntingtin (Htt), which when normal enhances the production of a protein (BDNF) necessary for the survival of the cells in the striatum and cerebral cortex.
Stay tuned for a post later this week on current experimental treatment on Huntington’s! Thank you for reading
Cummings, Michael. “Genetics of Behavior.” Human Heredity: Principles and Issues. 9th ed. Belmont: Brooks/Cole, 2011. 405-06. Print.
I am currently taking at genetics course at Duke University, hence the inspiration for my last post. One of my assignments also looked at a correlation between genetics and autism I thought I would share it on here! I hope you enjoy reading
A new study published in the American Journal of Human Genetics has found evidence suggesting a recessive genetic component to low-functioning autism. Professor Eric Morrow and his colleges of Brown University analysed the DNA of over 2,100 children born with autism into “simplex” families, families where only one child suffers from autism and no other immediate family (Brown University, 2013). Morrow et al. investigated the genomes of the autistic children and their siblings for “runs of homozygosity”; runs of homozygosity refer to long strands of DNA that are contributed to a child’s DNA by both parents (ibid). Morrow and his colleges discovered that the children with low-functioning autism had longer runs of homozygosity compared to the DNA of their siblings. Normally, as humans we do share large blocks of DNA sequences; nearly all the participants had at least 1 million letters in common. In fact, about 1/3 of all the participants had about 2.5 million shared letters, which translates to a “shared common ancestor approximately 40 generations or 1,000 years ago” (ibid). However, in 500 of the participants, where the autistic children had an IQ below 70, the runs of homozygosity surpassed even the 2.5 million mark and the runs of their siblings. The original article, titled “Intellectual Disability Is Associated with Increased Runs of Homozygosity in Simplex Autism” stresses that increased runs of homozygosity do not predict low-functioning autism; yet, a greater number does increase the likelihood of carrying the shared “recessive variants” necessary for developing low-functioning autism (Morrow et al., 2013). Basically, Morrow et al. concluded that the longer runs of identical DNA lettering meant that a child was far more likely than other children, even their own siblings to inherit rare genetic traits.
These findings are relevant to the course as they illustrate that a pedigree for low-functioning autism exists even if the carried recessive trait is extremely illusive in simplex families. Unfortunately, the whole picture of the genetics behind autism is still a bit of a blur; however, the established correlation between low-functioning autism and runs of homozygosity does suggest that inheritance does play a role and that individual errors are far less likely to be the only possible perpetrators of autism.
The role of inheritance in low-functioning autism is a breakthrough considering the elusiveness of the disorder. Currently, most genetic explanations for low-functioning autism focus on “spontaneous mutations and having too many or too few copies of a gene”; however, in some families these hypotheses fail to explain their particular case of autism (Brown University, 2013). Runs of homozygosity at least allows for parents to look somewhere new for answers. In fact, if a test is run on the child at an early age, high runs of homozygosity might help health professionals guide the development of the child by focusing treatment on the particular associated issues such as problems with speech and social interaction. With all genetic testing it seems people are weary; however, given that autism is very difficult to diagnose without symptoms, I feel that testing for runs of homozygosity in the early stages of a diagnosis can only be beneficial for parents trying to understand their child’s diagnosis. Furthermore, continued genetic testing on children from simplex families can only increase the likelihood of fine-tuning the genetic component of low-functioning autism.
Brown University (2013, July 3). DNA markers in low-IQ autism suggest heredity. ScienceDaily. Retrieved July 4, 2013, from http://www.sciencedaily.com/releases/2013/07/130703140236.htm
Assignment: Part of Biology 156 at Duke University
A new study lead by Professor Simon Baron-Cohen of Cambridge University suggests that girls with anorexia have a higher than average “number of autistic traits” (University of Cambridge, 2013). These traits include an “above average interest in systems” and a below average empathy score (ibid). Considering the rigid personality, attitudes and behaviours of anorexics and their obsessive thought patterns in relation to body weight, body image and eating patterns it is not difficult to see how they can be interpreted as typical of autism.
n the study, first published the Journal of Molecular Autism, Baron-Cohen et al. assessed 66 girls between the ages of 12 and 18 with anorexia but no history of autism for autistic traits. A control group of over 1,600 neurotypical teens in the same age group were also given the same assessments including the the Autism Spectrum Quotient (AQ), Systemising Quotient (SQ) and the Empathy Quotient (EQ). Results showed that compared with the control group, the anorexic girls were five times more likely to score in the autistic spectrum. More than 50% of the anorexic girls fell into the “broader autism phenotype” compared with only 15% of the control (ibid). Furthermore, the anorexic girls also scored a higher SQ and lower EQ which also points towards an autistic personality.
As interesting as these results are there is indeed a practical application. Cases of autism are far more prevalent in males; however, Baron-Cohen’s findings show that perhaps autism in young girls is being overshadowed by a diagnosis of anorexia. Dr Tony Jaffa, co-leader of the study confirms that the new correlation between autistic traits and anorexia will give health professionals and researchers a new means to help those suffering from the eating disorder. He remarks:
“For example, shifting their interest away from body weight and dieting on to a different but equally systematic topic may be helpful. Recognising that some patients with anorexia may also need help with social skills and communication, and with adapting to change, also gives us a new treatment angle”