piatok, 8. marca 2013

Errors of Attribution

What is attribution errors?

It's a psychological term for describing a process of inferring the cause of events or behavior without being aware of the underlying processes and biases that lead to those inferences.

What is Self-Serveing Bias?

 Its cognitive bias that tends to enhance the ego and self confidence of an individual, through a variety of processes. . Being aware of the processes behind it can help a person to evaluate his or her performance and progress more critically, and it will allow the person to use things like failures as learning experiences. For example if a person passes her driving test on the first try, she might say that this was due to the fact that she studied hard and is a good driver. If she fails the test, however, she might blame the examiner, the car, or the weather, rather than admitting that she did not demonstrate safe and effective driving skills.

Study based on evidence of the Self-serveing Bias -  Elizabeth Posey and Randolph A.Smith


Aim:  To investigate self-serving bias in children

Participants:  Twenty male and 16 female second graders 

Procedure: Children were paired with a partner of same gender and were asked to complete 3 minutes math worksheet as a group. But, one half of the participants was paired up with a friend while the other one was not. At the end all of them received feedback that indicated their success or failure.

Result: The people in non-friend groups were blaming the failure to their partners. When they were asked who did better job they tended to give a credit for themselves. On the contrary children who were paired up with a friend were less likely to blame others or external/situational factors for their failure.

Conclusion:  Participants who were blaming others for the failure clearly demonstrated self-serving bias. By putting the blame on their partners children wanted to protect their ego or self-esteem.
Aim:


Study based on evidence of cultural differences in relation to the Self-serveing Bias


Researches suggest  there are cultural differences in the fundamental attribution error, people form individualistic cultures are more prone to the error while people from collectivism cultures commit less of it.

Study of Kashima and Triandis

Who conduced it? Kashima and Triandis in 1986.

Participants: 34 Japanese graduate students and 202 American undergraduate students 

Procedure: Participants were shown and then asked to remember 15 slides pertaining to life in Israel, Greece and Iran. Then they were given 5-minute recognition test that was based on those slides. After the test the participants were shown 5 slides pertaining to life in India. Then they were given 3-minute test based on those 5 slides about India. Participants were randomly assigned to either success or failure group. People in the success group were told they scored 12/15 while the people in the failure group were told they scored only 5/15. Then all of the participants were given an attribution questionnaire.

Result: American students tended to attribute their success to their talent or abilities. Japanese students tended to attribute their failure to lack of their abilities. Both Americans and Japanese students responded similarly when they were given situational information










štvrtok, 7. marca 2013

Biology and Techhnology

There are 3 brain imaging technologies:

Computer Tomography (CT)

 What it is?

Computer Tomography is an imaging method that uses x-rays to create pictures of cross-sections of the body. The CT computer displays these pictures as detailed images of organs, bones, and other tissues. Tomography is the process of generating a two-dimensional image of a slice or section through a 3-dimensional object

Method   - First you will lie on a table that is attached to the CT scanner, which is a large doughnut-shaped machine. 
              - Second The CT scanner sends X-rays through the body area being studied. Each rotation of the scanner provides a picture of a thin slice of the organ on area
              - Third a dye called contrast material is used. It may be put in a vein in your arm, or into rectum or a joint to see those areas better. For some types of CT scans you drink the dye. The dye makes structures and organs easier to see on the CT pictures.

What is able to be learned through the use of each?

CT can be use to: - study all parts of human body  such as the chest, belly, pelvis, arm or leg.
                           - It can take pictures of body organs, such as the liver,pancreasintestines, heart....                                                                         -It also can study blood vessels, bones, and the spinal cord.

 What does the image shows?

The image shows your bones, organs, and soft tissues more clearly than standard x-rays and all at the same time. Because the picture is made by a computer, it can be enlarged to make it easier to see and interpret. It is also used by doctors to find a cancer. CT scan can be also used to guide needles into tumors for some types of cancer treatments, such as radiofrequency ablation


  Positron emission tomography

What is it?

It is is an imaging technique that uses radioactive substances injected into patients to provide images of the body using specialized scanners. These PET images provide information about the function and metabolism of the body's organs, in contrast to computed tomography (CT) or magnetic resonance imaging (MRI), which show the body's anatomy and structure. PET is used mainly to study patients with cancer, heart disease, and neuropsychiatric diseases.

Method: The patient is given tracer, usually given through  IV, asked not to eat 4-6 before the test. After the traces is absorbed, the patient is laid on a table and put into a special tube. The tracer goes through various organs through the blood system and is visible on monitors in 3-D which help diagnose the patient.

How can be PET used to explain human behavior?

It helps to diagnose brain damage, dementia or tell the difference between Parkinson's or other movement disease. For example, PET may show the spiral way of how the brain cells die, which is symptom of Alzheimer's disease 


Functioning Magnetic Resonence Imaging (FMRI)

What is it?

It measure brain activity by monitoring changes in blood.

Method: It works by detecting the changes in blood oxygenation and flow that occur in response to neural activity – when a brain area is more active it consumes more oxygen and to meet this increased demand blood flow increases to the active area.

What is able to learned through the use of FMRI?

FMRI can be used to produce activation maps showing which parts of the brain are involved in a particular mental process.

How can FMRI help to explain human behavior?

Scientists are able to go as far as "read mind" of a person by showing him/her a picture while in the machine, scanning which part of the brain is activated when the person thinks of this object/how to use it/ how to hold it/ his or her experience with it, and record this data. So far, people had very similar results for the same objects.






Henri Tajfel- Social Identity Theory


What is social identity theory?

Social identity theory is the way in which you can explain group behavior. It explain how people develop a sense of membership and belonging in particular groups, and how the mechanics of intergroup discrimination work.

          Henri Tajfel

Henri Tajfel  was a British social psychologist, best known for his pioneering work on the cognitive aspects of prejudice and social identity theory.  He believed that the cognitive processes of categorization contributed strongly to the psychological dimensions of prejudice. He had seen how large numbers of Germans– not just those with particular personalities – had given their support to Nazism and had held extreme views about Jews. Nazism would not have been successful without the support of ‘ordinary’ Germans. Tajfel sought to discover whether the roots of prejudice might be found in 'ordinary' processes of thinking, rather than in 'extraordinary' personality types.

Experiments in Intergroup Discrimination  ( 1970)

Tajfel  believes that the personality approach is inadequate in explaining prejudice and he also uses a social psychological approach.  Tajfel  argue that ‘competition’ is not a sufficient condition for inter-group conflict and hostility. 

Aim: His main aim was to investigate the minimal conditions in which prejudice and discrimination can occur In addition, he demonstrate that merely putting people into groups (categorisation) is sufficient for people to discriminate in favour of their own group and against members of the other group.

Participants: There were 64 boys between 14 and 15 years old from a comprehensive school in a suburb of Bristol.

Method: They came to the laboratory in separate groups of 8. All of the boys in each of the groups were from the same house so that they knew each other well before the experiment.
At first the boys were brought together in a lecture room and were told that experimenters are interesting in the study of visual judgements.  Forty clusters of varying numbers of dots were flashed on a screen and the boys were asked to record each estimate in succession on prepared score sheets.



Procedure: After the boys had completed their estimates they were told that in judgments of this kind some people consistently overestimate the number of dots and some consistently underestimate the number. 
  After the judgments had been made they were “scored” by one of the experimenters.
vParticipants were told that researchers were interested in other decision making processes & were going to take advantage of their presence to investigate these. Participants were told they were be grouped on the basis of the visual judgements they had just made.
The experimenters were given the instructions and introduction about this experiment. The task consists of giving  others participants points which would then be converted into real money at the end of the experiment.
Participants did not knew the identity of the individuals to whom they would be assigning
Each boy went to another room on their own, and was given a booklet containing 18 pages
 On each page there were 14 boxes containing two numbers each
The numbers in the top row of the matrix were the rewards and penalties to be awarded to one person and those in the bottom row were those to be awarded to another. They were not giving money to themselves.
At the end of the task each boy were brought back into the first room and would receive the amount of money the other boys had awarded him
The value of each point they were awarding was a tenth of a penny
Each row of the matrix was labeled # of over estimators and # of under estimators
The boys were required to make three types of choice.
There were in-group choices, where both top and bottom row referred to members of the same group as the boy. (other than himself)
There were out-group choices, with both top and bottom row referred to members of the different group from the boy.
There were intergroup choices, where one row referred to the boys’ own group and one row referred to the other group.

 Result: In the intergroup choices the large majority of participants gave more money to members of their own group. When the boys had an entirely in-group (or out-group) choice to make, they tended towards the point of maximum fairness (this would be 0 and –1 in our example). 

Conclusion: Discrimination occurred as a result of simply designating in-group and out-group membership. Choices were not made to maximize everyone’s winnings but instead to maximize group profits.

streda, 20. februára 2013

Importance of Situational Factors

   Milgram Studies of obedience to authority (1974)

Aim:  Milgram was interested in researching how far people would go in obeying an instruction if it involved harming another person.  Stanley Milgram was interested in how easily ordinary people could be influenced into committing atrocities for example, Germans in WWII.

Participants: Participants were 40 males, aged between 20 and 50, whose jobs ranged from unskilled to professional. Milgram selected participants for his experiment by advertising for male participants to take part in a study of learning at Yale University. He tries to focusing on the conflict between obedience to authority and personal conscience. 

Prodedure: Volunteers were recruited for a lab experiment investigating learnin.
At the beginning of the experiment they were introduced to another participant, who was actually a confederate of the experimenter (Milgram).  They drew straws to determine their roles – leaner or teacher – although this was fixed and the confederate always ended to the learner. There was also an “experimenter” dressed in a white lab coat, played by an actor.

The “learner” (Mr. Wallace) was strapped to a chair in another room with electrodes. After he has learned a list of word pairs given him to learn, the "teacher" tests him by naming a word and asking the learner to recall its partner/pair from a list of four possible choices.
The teacher is told to administer an electric shock every time the learner makes a mistake, increasing the level of shock each time. There were 30 switches on the shock generator marked from 15 volts (slight shock) to 450 (danger – severe shock).

The learner gave mainly wrong answers and for each of these the teacher gave him an electric shock. When the teacher refused to administer a shock and turned to the experimenter for guidance, he was given the standard instruction consisting of 4 prods:

Prod 1: Please continue.

Prod 2: The experiment requires you to continue.

Prod 3: It is absolutely essential that you continue.

Prod 4: You have no other choice but to continue.

Result: 65% of participants (i.e. teachers) continued to the highest level of 450 volts. All the participants continued to 300 volts.

Milgram did more than one experiment – he carried out 18 variations of his study.  All he did was alter the situation (IV) to see how this affected obedience (DV).

Conclusion: Ordinary people are likely to follow orders given by an authority figure, even to the extent of killing an innocent human being.  Obedience to authority is ingrained in us all from the way we are brought up. Such as parents, teachers, anyone in authority.

Strenghts: As the experiment was conducted in a laboratory setting, it allowed the experimenter to have a high level of control. This is useful as it makes the results more reliable as we can say that we can observe the effects of Milgram’s commands to the participants clearly.

Weakness: Participants of Milgram’s study were deceived as they were told the experiment was about “the effects of punishment on learning” and were made to believe that they were giving real electric shocks to participants. (Milgram thought this necessary for the study because if the participants knew about the true aim of the study, demand characteristics would be introduced, and the findings of the study would be useless.)




                                 

             Asch's Studies of comformity (1956)

 Aim: Solomon Asch (1951) conducted an experiment to investigate the extent to which social pressure from a majority group could affect a person to conform.

Participants: There were 123 male students from Swarthmore College in the USA participated in a ‘vision test’. They believed they were participating in a visual discrimination task.
 
Procedure: Asch used a lab experiment to study conformity, whereby 123 male students from Swarthmore College in the USA participated in a ‘vision test’.  Using the line judgment task, Asch put a naive participant in a room with four to six confederates.  The confederates had agreed in advance what their responses would be when presented with the line task.  The real participant did not know this and was led to believe that the other seven participants were also real participants like themselves.  Each person in the room had to state aloud which comparison line (A, B or C) was most like the target line. The answer was always obvious.  The real participant sat at the end of the row and gave his or her answer last.  In some trials, the seven confederates gave the wrong answer.  There were 18 trials in total and the confederates gave the wrong answer on 12 trails (called the critical trials).  Asch was interested to see if the real participant would conform to the majority view.

Results: Asch measured the number of times each participant conformed to the majority view.  On average, about 32% of the participants who were placed in this situation went along and conformed with the clearly incorrect majority on the critical trials.  Over the 12 critical trials about 75% of participants conformed at least once and 25% of participant never conformed.

Conclusion: Why did the participants conform so readily?  When they were interviewed after the experiment, most of them said that they did not really believe their conforming answers, but had gone along with the group for fear of being ridiculed or thought "peculiar".  A few of them said that they really did believe the group's answers were correct.
Apparently, people conform for two main reasons: because they want to fit in with the group (normative influence) and because they believe the group is better informed than they are (informational influence).
 

Strengths: The strength of this study is that the experiment was simple so it was easy to record the results. The experiment also well demonstrated Asch’s theory.

Weakness: The weakness of Asch’s study is that it was not completely controlled. Another weakness is that it deceivable.




        Zimbrado's Stanford Prison experiment (1971)
 Aim: To investigate how readily people would conform to the roles of guard and prisoner in a role-playing exercise that simulated prison life.

Zimbardo (1973) was interested in finding out whether the brutality reported among guards in American prisons was due to the sadistic personalities of the guards or had more to do with the prison environment.

Participants: From more than 75 people who responded to the ad, 24 students were chosen: 12 to role play prisoners (9 plus 3 alternates) and 12 to role play guards (also 9 plus 3 alternates). These students had no prior record of criminal arrests, medical conditions, or psychological disorders.
 They played the roles of prisoners and guards. 
Students were screened for psychological normality and paid $15 per day to take part in the experiment.
  
Procedure: Participants were randomly assigned to either the role of prisoner or guard in a simulated prison environment. Prisoners were arrested at their own homes, without warning, and taken to the local police station.

Guards were also issued a khaki uniform, together with whistles, handcuffs and dark glasses, to make eye contact with prisoners impossible. No physical violence was permitted. Zimbardo observed the behavior of the prisoners and guards.



Here they were treated like every other criminal.  They were fingerprinted, photographed and ‘booked’.  Then they were blindfolded and driven to the psychology department of Stanford University, where Zimbardo had had the basement set out as a prison, with barred doors and windows, bare walls and small cells.  Here the deindividuation process began.
When the prisoners arrived at the prison they were stripped naked, deloused, had all their personal possessions removed and locked away, and were given prison clothes and bedding. They were issued a uniform, and referred to by their number only. Their clothes comprised a smock with their number written on it, but no underclothes. They also had a tight nylon cap, and a chain around one ankle.
There were 3 guards to the 9 prisoners, taking shifts of eight hours each (the other guards remained on call)

Results:

Within a very short time both guards and prisoners were settling into their new roles, the guards adopting theirs quickly and easily.
Within hours of beginning the experiment some guards began to harass prisoners. They behaved in a brutal and sadistic manner, apparently enjoying it. Other guards joined in, and other prisoners were also tormented.
 The prisoners were taunted with insults and petty orders, they were given pointless and boring tasks to accomplish, and they were generally dehumanized.
The prisoners soon adopted prisoner-like behavior too.  They talked about prison issues a great deal of the time. They ‘told tales’ on each other to the guards. They started taking the prison rules very seriously, as though they were there for the prisoners’ benefit and infringement would spell disaster for all of them. Some even began siding with the guards against prisoners who did not conform to the rules.
Over the next few days the relationships between the guards and the prisoners changed, with a change in one leading to a change in the other.  Remember that the guards were firmly in control and the prisoners were totally dependent on them.
As the prisoners became more dependent, the guards became more derisive towards them. They held the prisoners in contempt and let the prisoners know it. As the guards’ contempt for them grew, the prisoners became more submissive.
As the prisoners became more submissive, the guards became more aggressive and assertive. They demanded ever greater obedience from the prisoners. The prisoners were dependent on the guards for everything so tried to find ways to please the guards, such as telling tales on fellow prisoners.

One prisoner had to be released after 36 hours because of uncontrollable bursts of screaming, crying and anger. His thinking became disorganized and he appeared to be entering the early stages of a deep depression. Within the next few days three others also had to leave after showing signs of emotional disorder that could have had lasting consequences. (These were people who had been pronounced stable and normal a short while before.)
Zimbardo (1973) had intended that the experiment should run for a fortnight, but on the sixth day he closed it down. There was real danger that someone might be physically or mentally damaged if it was allowed to run on. After some time for the researchers to gather their data the subjects were called back for a follow-up, debriefing session.

Conclusion: 
  1. Some situations can exert powerful influences over individuals, causing them to behave in ways they would not, could not, predict in advance.
  2. Situational power is most salient in novel settings in which the participants cannot call on previous guidelines for their new behavior and have no historical references to rely on.
  3. Situational power involves ambiguity of role boundaries, authoritative or institutionalized permission to behave in prescribed ways or to disinhibit traditionally disapproved ways of responding.
  4. Role playing -- even when acknowledged to be artificial and temporary -- can still come to exert a profoundly realistic impact on the actors.
  5. Good people can be induced, seduced, initiated into behaving in evil (irrational, stupid, self destructive, antisocial) ways by immersion in "total situations" that can transform human nature in ways that challenge our sense of the stability and consistency of individual personality, character, and morality. 

 Strengths: A further strength was in the way that Zimbardo collected data.  He used a number of qualitative approaches such as observation (sometimes overt and sometimes covert) interviews and questionnaires. 


Weakness: The only deception involved was to do with the arrest of the prisoners at the beginning of the experiment.  The prisoners were not told partly because final approval from the police wasn’t given until minutes before the participants decided to participate, and partly because the researchers wanted the arrests to come as a surprise.  However this was a breach of the ethics of Zimbardo’s own contract that all of the participants had signed.  

Sperry and Gazzaniga: The Split Brain Study

1. What does it mean for a person's brain to be "split
2. What was the reason why this procedure was performed on patients?
3. Explain one of the tests Sperry and Gazzaniga performed on these split brain patients.
4. What were the results of this test?
5. What is the reason that these results occurred?
6. What is the corpus callosum and what role does it serve in your brain?






1. Each hemisphere is still able to learn after the split brain operation but one hemisphere has no idea about what the other hemisphere has experienced or learned. Today, new methods and technology in split brain operation make it possible to cut off only a tiny portion and not the whole of the corpus callosum of patients.


 
2. The experiments were undertaken on people who had already had their corpus callosum severed as treatment for severe epilepsy in the 1960s. Epilepsy is a kind of storm in the brain, which is caused by the excessive signaling of nerve cells, and in these patients, the brain storm was prevented from spreading to the other hemisphere when the corpus callosum was cut off. This made it possible for the patients to live a normal life after the operation



3. The participants were 11 ‘split-brain’ patients. The participants had all undergone hemisphere deconnection because they had a history of advanced epilepsy which could not be controlled by medication.
The method used was a natural experiment called also quasi-experiment. These experiments involved comparing the performance of the 11 participants on various tasks with the performance of people with no inter-hemisphere deconnection. The independent variable was therefore the whether a person had hemisphere deconnection or not and the dependent variable was the participants performance on the tasks.
Sperry used a number of ingenious tasks in order to investigate lateralisation of brain function. The tasks were carried out in laboratory conditions, using specialised equipment and were highly standardised. The task all involved setting task separately to the two hemispheres.
The tasks used to send information to just one hemisphere involved asking patients to respond to tactile information. This involved presenting a stimulus to one of the hands of a split-brain patient so the participant could not see the stimulus and then asking the participant to name it. If the stimulus is presented to the participant’s left hand the participant should not be able to name it.
It is also possible to present Auditory (sound) and olfactory (smell) stimuli to one side of the brain using various methods of blocking the unused ear or nostril.



4.When participants were presented with an image in one half of their visual field and then presented with the same image in the other half of the visual field they responded as if they had never seen the image before. If the same image was presented in the original visual field the participants were able to recognise the image as one they had seen before.
Participants were not able to give a description of an image that was presented to the left hand side of the visual field. The image was either not noticed or just appeared as a flash. But they could respond non-verbally by pointing with their left hand to a matching picture or selecting an object presented among a collection of other pictures and objects. This works only with right-handed participants.
If two symbols were presented simultaneously, one on either side of the visual field for example a dollar sign on the left and a question mark on the right hand and the participant was required to draw with their left-hand what they had seen, they would draw the left visual field symbol a dollar sign. If they were required to say what they had just drawn, the participant would say by name, the right visual field symbol a question mark.
Objects put in the participants hand for identification by touch could be described or named in speech or writing if they were in the right hand but if placed in the left hand, the participant could either only make wild guesses or even appeared to be unaware that anything at all was present. However, if the object was taken from the left hand and placed in a ‘grab bag’, or was scrambled among other test items, the participant was able to search out and retrieve it with their left hand.
Sperry showed that split-brain patients were better at completing highly unusual tasks that this would have no advantage in the real world.
Through the case studies Sperry found that the hemisphere deconnection did not appear to affect the patients’ intelligence (as measured by an IQ test) or their personality. The effects of the surgery did seem to have affected the patients in that they had short-term memory deficits, limited concentration spans and orientation problems.


5. Research showed that split brain patients present superiority on the right hemisphere when it comes to spatial tasks, such as arranging blocks. Researchers also showed drawings to the left and right hemispheres and the patient was asked to draw what he saw from both hemispheres. The conclusions were that the left-handed drawings were better drawn.






6. Corpus callosum is a type of epilepsy which is caused by the excessive signaling of nerve cells. By cutting the corpus callosum which connects the two cerebral hemispheres the brain storm was prevented from spreading to the other hemisphere.














utorok, 22. januára 2013

Stroke: An Assault on the Brain

What happend to the brain when a stroke occurs?

Brain cells suddenly die because of a lack of oxygen. This can be caused by an obstruction in the blood flow, or the rupture of an artery that feeds the brain. The patient may suddenly lose the ability to speak, there may be memory problems, or one side of the body can become paralyzed.







 Three types of stroke:


First is Ischemic stroke that accounts for about three-quarters of all strokes. Occurs when a blood clot, or thrombus, forms that blocks blood flow to part of the brain. If a blood clot forms somewhere in the body and breaks off to become free-floating, it is called an embolus. This wandering clot may be carried through the bloodstream to the brain where it can cause ischemic stroke.

Second is a Hemorrhagic stroke that occurs when a blood vessel on the brain's surface ruptures and fills the space between the brain and skull with blood called subarachnoid hemorrhage or when a defective artery in the brain bursts and fills the surrounding tissue with blood called cerebral hemorrhage.

Third is Transient Ischemic Strokes (TIA) that occurs when a blood clot blocks an artery for a short time. TIAs may occur days, weeks or months before the onset of a stroke. The symptoms of a TIA are like the warning signs of a stroke, but they usually last only a few minutes. TIAs are strong predictors of stroke risk. Don’t ignore them. Call 9-1-1 or seek emergency medical attention immediately.







 What disabilities can result from a stroke?


It depends on where the stroke occurs and how much of the brain is affected. Smaller strokes such as TIA may result in minor problems, such as weakness in an arm or leg. Larger strokes such as Ischemic or hemorrhagic strokes may lead to paralysis or death. Many stroke patients are left with weakness on one side of the body, difficulty speaking, incontinence, and bladder problems. 


 Who is most likely to have stroke?


  • People over age 55
  • Male
  • African American, Hispanic or Asian/Pacific Islander
  • A family history of stroke
  • High blood pressure
  • High cholesterol
  • Smoking cigarettes
  • Diabetes
  • Obesity and overweight
  • Cardiovascular disease
  • A previous stroke or transient ischemic attack (TIA)
  • High levels of homocysteine (an amino acid in blood)
  • Birth control use or other hormone therapy
  • Cocaine use
  • Heavy use of alcohol - heavy regular drinkers have a considerably higher risk of stroke early in life compared to others.
  • Men from divorced families have a higher chance of suffering a stroke than those from families which are still intact

What is brain plasticity and what does it mean in terms of recovering from a stroke? 

All of these ailments are treated through speech and language therapy. Brain plasticity makes improvements in communication skill. This distinctive trait makes the brain a very valuable organ, as it can constantly adapt itself to deal with new input and information. There are two different types of brain plasticity:
The First type is Functional Plasticity that occurs when infants are born and start developing into children. Studies have shown that the immature brain grows and creates neural networks at an unprecedented rate, as the brain is flooded with new sensory input from the outside world.
The second type is Structural Plasticity that occurs over the course of a lifetime, as the brain changes with age to reflect new experiences and events as a result of learning.


How does Brain Plasticity Work?


Plasticity refers to the brain's ability to repair and reorganize cells. This means having healthy cells of the brain taking over jobs that were previously carried out by brain cells which were destroyed.
This is done by sprouting of new synaptic connections and creating new pathways to unaffected parts of the brain.
Brain plasticity The brain's plasticity appears to be greatest when we are young. You can probably recall how much easier it was to learn, such as a foreign language or a musical instrument, when you were younger.
Of course our ability to learn new skills continues as we become adults. This indicates that the brain retains a certain level of plasticity throughout our lives.
When neurons, the primary cells of the nervous system, are damaged by a stroke or brain injury, other neurons take over for them. This adaptive behavior allows us to reorganize the brain in an effort to recover lost skills.