Transcript for:
Psychopathology and Research Methodology

loved ones recipe here and welcome to my virtual classroom now we are going to be going over some crucial material the first lecture is going to be an introduction to the material that we will cover this semester and the methodology of research within the study of psychopathology so who's ready for an adventure no not really it's pretty boring stuff as you asked me but hey got to know it not only for the exam but to be successful in a psychology field so roll that intro [Applause] [Music] [Applause] so the first topic is defining abnormal behavior now I'm still not too sure what normal behavior is so defining abnormal behavior is a bit I don't know abnormal anywho there are various criteria used to define abnormal behavior psychologists generally consider behavior abnormal when it meets some combination of the following criteria one unusual or infrequent to socially unacceptable or in violation of social norms three fraught with misperceptions or misinterpretations of reality four associated with stasis severe personal distress five maladaptive or self-defeating and fix dangerous well doesn't that mean normal behaviors is the opposite of that debatable I guess so a psychological disorder consists of abnormal behaviors it can be a state of severe distress such as depression or anxiety or with impaired behavior or the inability to function properly such as difficulty holding a job or distinguishing reality from fantasy the branch of psychology that studies psychological disorders describes them determines causes and how to treat them is that normal psychology I'd never thought I'd see just or someone like that you know I'm a police photographer and I've shot some pretty grisly stuff corpses and all crime scenes are not like what you see on TV they're more grisly I guess you sort of get used to it it never bothered me just maybe at first before I did this job I worked on a TV news chopper we would take shots of fires and rescues you know now I get uptight sitting in the backseat of a car or riding an elevator I'll avoid taking an elevator unless I really have no other choice forget flying and more it's not just helicopters I just won't go in a plane any kind of plane I guess I was younger than and more daring when I was younger sometimes I would hang out at the helicopter to shoot pictures with no fear at all now just thinking about flying makes my heart race it's not that I'm afraid the plane will crash that's the funny thing not haha funny but peculiar you know I just start trembling when I think of them closing that door trapping us inside I can't tell you why disorder is a pattern of abnormal behavior that is associated with states of significant emotional distress such as anxiety or depression or with impaired behavior or ability to function such as difficulty holding a job or even distinguishing reality from fantasy abnormal psychology is the branch of psychology that studies abnormal behavior and ways of helping people who are affected by psychological disorders as stated before this list is commonly used by psychologists to determine abnormal behaviors however the list is a bit vague let's take a look at each unusualness is any behavior that is unusual or just doesn't seem quite right searing and heat seeing and hearing things that are not actually there are almost always considered abnormal and our culture and many others but such experiences are sometimes considered normal and certain types of spiritual or religious experiences when people state that God or Jesus spoke to them they are not necessarily hearing someone speak words into their ear they mean it more as God or Jesus given them a sign and this sign is an indicative of them seeing things either they don't necessarily mean that God or Jesus appeared to them in a humanoid form directly in front of them they could mean it as a natural sign in their environment that God or Jesus put in front of them however if they did mean it like that and some religious beliefs or even cultures that isn't considered abnormal the majority of people do not experience anxiety or excessive worry fulness however for those who do experience anxiety upon entering a crowded building such as those as a mall or maybe an amusement park on a holiday weekend may be considered abnormal because for most they don't experience these symptoms but what about people who excel at particular tacks are they abnormal because the majority of people cannot perform the task as well as them in the US only 32 percent of the population aged 25 and over have obtained a bachelor's degree only twelve percent of the population aged 25 and over have obtained a master's degree or higher and only two percent age 25 and over have obtained a doctorate degree when you graduate from college does that make you abnormal am i abnormal well the point is just because you belong to a population that isn't the majority does not make you have normal rarity or statistical divvy ins is not sufficient is not a sufficient basis for labeling behavior nevertheless it is just often just used to measure or judge abnormality social deviance all societies have norms or standards on which behaviors are accepted in certain situations environments or contexts behavior that is deemed normal in one culture may be viewed as abnormal by another pic hand-holding when we hold hands in the u.s. it is saying that the two are in a relationship when we see two men or two or two women holding hands we also assume they are in a relationship but if we were to take a trip to India we will also see the same thing people holding hands however it is more common to see two men holding hands who are not in a relationship or even homosexual for that matter in India holding hands is considered a way of showing affection and bonding and camaraderie in the u.s. we automatically assume two men or two women holding hands to be homosexuals we look at it differently thus clinicians need to weigh cultural differences and determining abnormality time also affects what is considered abnormal behaviors again let's discuss homosexuality homosexuality was once considered a psychiatric disorder but by the mid 1970s began to change today homosexuality is not labeled in the DSM and not considered a mental disorder and many people argue that homosexuality should be included as a normal variation of behavior however there are still plenty of people who do not and just because some behaviors we do not approve of does not mean that the person is sick or has some type of mental illness people still label them as so though perhaps it's a Freudian defense mechanism which we will discuss those later ulti perceptions like hallucinations such as same things are people that are not there or hearing voices from others that are not present are not considered normal delusions such as the delusion of persecution such as believing the police are after youth when they are not is also not considered normal or experienced by the majority we discussed this partly already earlier when discussing religion face of personal distress caused by anxiety fear or depression may be abnormal however there are times where it is seen as normal behavior such as becoming sad or depressed when a loved one passes our loved one passes away in in cases like this it may be it may seem abnormal not to have these feelings these feelings anxiety fear depression are considered abnormal if they persist long after the source of the feelings and the cause of the feelings occurred or if there are so intense that it disrupts a daily functioning maladaptive or self-defeating behaviors is behavior performed by someone that or someone that leads to unhappiness rather than stuff fulfillment this is considered abnormal behavior that limits a person's ability to perform and they're expected roles such as jobs or parenting or adapt to their environments may also be considered abnormal think about this we all know that alcohol impairs our cognition or our ability to think clearly yet there are plenty of people who drink too much on a daily basis they know they need to slow down or quit altogether but just quit right they wake up late have hangovers go to work hungover and can perform as their job and a various amount of other negative things are impacted by alcohol use yet they continue to drink this is a self-defeating behavior and it's considered abnormal and this person will be labeled as an alcoholic damn it I guess I got to put this down now and dangerousness these are behaviors that people partake and that are dangerous to oneself or to others as like before social context is crucial as one who targets at a car on fire to rescue the people inside the burning car is considered a hero even though that was a very dangerous behavior there are others that threaten suicide or killing others in a violent act this is considered abnormal so we can see that admirable behavior may be more difficult to define and initially thought we must take into account the situation environment time culture and a whole range of other aspects before we can define a behavior as abnormal mental disorders vary greatly in how they affect the individuals who have them and how they might appear to an outsider they may be so mild as to be almost unnoticeable or so severe that they affect an individual's ability to function normally because of this variability and because mental disorders are difficult to see they remain shrouded in mystery for many people so let's start with what we know and what we aren't sure about how would you define mental disorders what causes them are they influenced most by how we are raised or by our genes how treatable or curable are mental disorders a mental disorder is typically defined as being a behavioral or psychological symptom or pattern that's associated with significant amounts of distress or disability and particularly we think about this in terms of impaired functioning and their normal social lives or professional lives and it's important to note that any context that we want to discuss a mental disorder in it is going to be relative right so there are different norms by each culture for each Society depending on where you live certain things are normal other things are not normal so the context is always important when evaluating anything we want to say is normal or abnormal but in general we know that psychological distress and impaired functioning is a key feature of most mental disorders in general we can't say that anything in particular causes mental disorders so what we think about now is more risk factors and what might leave people more predisposed and there's three categories of factors that may contribute to these risk factors there biological psychological and socio-cultural it's tough to say whether something could really be preventable and that we don't really fully understand the true root cause of a mental disorder we know that certain individuals may be less predisposed than others people develop things like resilience or certain other types of coping mechanisms that allow them to perhaps cope better with certain adverse events in life and thus be less likely to exhibit signs and mental disorders but certainly there are a rich array of treatment options available for just about every disorder and so individuals should also know that if one particular type of treatment option doesn't work for them it doesn't mean that they can't be treated it means there are other options and maybe something else would be a better fit for them a different style of therapy a different therapist perhaps a different type of drug treatment so we do have a lot of different options in our arsenal for treating mental disorders as far as saying whether or not something is curable again it really depends it depends on how well the individual adapts and takes those skills that they may learn in therapy and is able to use them later in life and draw on them to cope with other adverse events that they may experience so again there's no one right or wrong or saying something's curable or not it really depends on the individual and on the disorder we know that genes do play a role in certain mental disorders but it's tough at this point to understand fully what the role of genes are versus our environment versus the other experiences that we have so for certain conditions like depression or schizophrenia we know that there are genetic links we know that the odds are slightly higher for individuals who have parents with any of those disorders we don't know exactly what might lead one individual with that genetic history to exhibit signs of depression versus another what we do know that there's a predisposition or a risk factor there as we start to understand better the role of genetics in risk factors for these mental disorders the better equipped will be to help individuals with potential risk factors develop appropriate coping mechanisms an individual's up brain can certainly play a role in how likely they are to exhibit mental disorders at later stages we know for instance that children who are raised in homes where there's a lot of marital discord wind up showing more signs of aggression towards their peers they can wind up being bullies so certainly we see our parents and we model that behavior we learn from our environment that's not to say again though that we're no inevitably destined to act just like our parents did as adults we can be aware of those patterns or those predispositions or habits and we can take steps to change them and address them proactively well it's hard to say something as normal or not normal because normal is really a relative term right what's normal in New York City certainly wouldn't be considered normal in many cases if you look at Omaha Nebraska but from a psychological perspective when we talk about what's normal behavior we're really referring to healthy adaptive functioning both at a professional and personal level so does the person have a healthy degree of relationships with their peers with others in their environment and family friends are they able to you know go to classes or go to their job and perform at a reliable consistent level day in and day out and as far as normal also the most important thing is what's mental to you so you know yourself certainly better than anyone else does and if you start to notice that for instance every day you're feeling a little bit down or you don't have interest in doing things that you used to like to do you don't really want to see your friends anymore or everything starts to feel like hopeless or bad then for you that that's not normal and you know that and that might be an appropriate time to consider talking to a professional it's clear that many of us have questions and concerns about mental disorders do you think someone you know has a disorder do you worry that you might and if so what are the options fortunately thanks to a great deal of research there are many good answers to the questions you might have and many good therapy options available we'll be exploring the diagnosis and treatment of disorders and explaining how to find help if you need it now let's take a look into the history of the study and the treatment of psychological disorders and abnormal behaviors many ancient societies attributed abnormal behavior to divine or supernatural forces they believed that this behavior was caused by the inhabitation of evil spirits and it was treated by manually drilling holes into people's skulls to release the spirit or demon that possessed them this was called trepanation many skulls that were found show fresh bone growth suggesting that many survived this process and remember there was no anesthetics back then either yikes now there still isn't proof that trepanation was performed because of demonic possession because no written record exists for the purpose of treffen ii it could have been used for another purpose there is no way to be absolutely certain however this notion of supernatural causes of abnormal behavior persisted throughout Western society until the Age of Enlightenment pretty scary huh in ancient Greece the philosopher Hippocrates ever great what's up Hippocrates believed that abnormal behaviors reflected natural causes he believed that the body had an imbalance of one or more of four humors or bodily fluids of the body these consisted of phlegm black bile blood and yellow bile too much phlegm the person was lethargic or sluggish too much black bile was thought to cause depression excess amounts of blood created a sanguine disposition meaning the person was cheerful confident and optimistic and an above average mouth of yellow bile will start to cause a person to be quick-tempered now of course this has been debunked however it served a greater purpose this was the first time that psychological disorders were thought to stem from biological processes in medieval times in Western societies it was still believed that abnormal behaviors were due to possession by evil spirits the Catholic Church taught and reinforced these ideologies and offered exorcisms as treatments now we've all seen the Exorcist movie the power of Christ compels you the power of Christ compels you but the devil behind you my son but the devil behind you know demonic possession and exorcism were not like that at all but profess to me is based on a true story exactly it's based on a true story it's not a true story I bet 90% of that movie didn't even occur to cease however exorcism did use prayer incantations or use or the use of spells waving across at the victim some did get violent and including including beating and even starving the victim from the late 15th to late 17th century there were many persecutions of women believed to be witches and supposedly perform satanic rituals to summon the devil and his demons however modern scholars believe these so-called witches were actually people with psychological disorders who were persecuted and even executed because of their abnormal behaviors by the late 15th and early 16th century mental asylums started to appear throughout Europe conditions and these asylums were dreadful and in some such as the Bethlehem Hospital in England a circus atmosphere prevailed with the rise of moral therapy in the in the 19th century largely spearheaded by the Frenchman jean-baptiste busine and Philippine Pannell condition in these mental hospitals improved so with busine and pinnell spearheading the reform movement and arguing for more moral therapeutic techniques to be used again conditions improved and many supported prasena and pinnell proponents of moral therapy believed that mental patients could be restored to functioning if they were treated with dignity and understanding Dorothea Dix a proponent of moral therapy in the u.s. and 1800 traveled all over the country speaking about the horrific conditions in jails and our Elms houses and as a result of her speaking out thirty-two mental hospitals were established in the United States however a decline in moral therapy in the latter part of the nineteenth century led to a period of apathy and to the belief that the end of the insane could not be successfully treated conditions and mental hospitals deteriorated and the hospitals offered little more than custody' or a little more than custodial care in the middle of 20th century public outrage and concern about the plight of mental patients mobilized legislative efforts toward the development of community mental health centers and alternatives to long term hospitalization this movement toward D ensues the institutionalization was spurred by the introduction of psychoactive draw call phenothiazines which curbed the more flagrant features of schizophrenia so in 1963 Congress established a nationwide system of community mental health centers they were to support mental institutions and a former hospital residence by creating community-based care and structured residential treatments residential treatment settings such as halfway houses while this seems like a great alternative to mental healthcare it has not lived up to the expectations with many discharged patients left and in adequate housing and lacking other forms of support they needed to function many mental health patients roam the streets homeless there has been some success but there are still many patients who mental health problems fail to receive the services they need CMHC's community mental health centers are severely underfunded and unable to reach many of the people that need its services if the institutionalization is going to work patients need continuing care and opportunities for decent housing gainful employment and training and social and vocational skills with today's state hospital is generally more focused on medication and psychiatry it's an improvement but still outpatient mental health care has a long way to go switching topics to contemporary perspective of abnormal behavior there are four main contemporary views on abnormal behavior to are listed here the biological and the psychological perspectives the biological model explains abnormal behavior in terms of biological defects or abnormalities and disorders can be classified according to distinctive causes and symptoms as stated earlier Hippocrates stated a biological influence on behavior while his theory on the imbalances of four humors were false it was the first time that behavior was thought to have a biological basis and he was right about that part even though it wasn't really studied scientifically until eighteen and 1900s there is a load of different chemicals called neurotransmitters in the brain and when there is an imbalance of these transmitters abnormal behaviors such as depression and mania can occur damage to certain areas of the brain from traumatic brain injuries and strokes can also lead to abnormal behaviors several diseases can also lead to abnormal behaviors if gone untreated such as syphilis which can cause general paresis general paresis is associated with physical symptoms and psychological impairments including personality and mood changes and with progressive deterioration of memory memory functioning and judgment the discovery of the cure for syphilis led to an optimism that biological causes for other types of disturbed behavior would be discovered our dimers disease also a brain disease which is a major cause of dementia let's further support to the biological perspectives of psychology the psychological perspective focuses on psychological roots of abnormal behavior and includes psychoanalytic behavioral humanistic and cognitive models Sigmund Freud was the first major influential person in developing the psychodynamic model the first major psychological model of abnormal behavior he believed that the unconscious mind had more influence of our daily behaviors than we realized and the causes of psychological problems lied outside of conscious awareness he would use hypnosis to discover with his patients built up emotions and allowed them to discharge them the last two our socio-cultural and biopsychosocial perspectives the socio-cultural perspective examined the broader social context in which abnormal behavior occurs socio-cultural theorists believe that abnormal behavior is caused by social ills and failures of society rather than the person themselves this can be due to unemployment poverty breakdown injustice ignorant and lack of opportunity think about it any of those things could cause depression or anxiety with unemployment and poverty someone may not know if they will be able to eat that day or feed their children this can be very debilitating for many injustice can cause various amounts of mental health issues such as depression as well think about all the recent news stories of people getting away with murder granted the prosecution attorneys failed to present enough evidence such as Trayvon Martin and more recently Josue Flores and John Hernandez Martin's killer was set free all charges against Florida's killer were dropped a few weeks ago while her Nana's case is still up in the air at least at the time of me recording this lecture in mid-july knowing that there is no justice can also be debilitating and could cause anxiety depression and even suicidal thoughts or attempts now I don't want to come across as being antagonistic towards the court system as I do believe in the court system to prove those who are guilty as guilty and assume that people are innocent until proven guilty but I just want to point out the fact that the Martin family had no closure to Trayvon debt which can be hard for the entire family friends and in this case the entire black community same for the floors and Hernandez cases and lastly the biopsychosocial model this perspective is an interactionist model and abnormal behavior is viewed as the result of the interplay of biological psychological and socio-cultural factors this take this takes the previous three perspectives and lumps them together as interacting with one another to describe as the normal behavior it's really just one factor that influences abnormal behavior it's usually a combination of the three there are many different types of disorders and a number of ways in which psychologists go about understanding and treating them four of the most common types of mental disorders are anxiety disorders mood disorders autism spectrum disorders and schizophrenia psychologists look at biological psychological and social factors when studying and treating these conditions major depression is a disorder that could be described as a person who experiences persistent low mood it affects that person's ability to function normally biological component of depression has to do with disruption of sleep so this could be not having enough sleep which is insomnia or sleeping too much or disruption of one's appetite affecting that person in terms of gaining too much weight or having weight loss psychological component a person may feel sadness hopelessness or thinking negatively or pessimistically the social component lack of interest in the things that one normally enjoys and also withdrawing from friends and other social activities you're absolutely alone you know you feel you are alone you feel absolute worthlessness you feel that there's no hope in the future there's as you believe everything is dissolving you feel you've met your marriage maybe dissolving relationships with children maybe dissolving all this kind of thing anxiety disorders group of disorders that's characterized by three general categories of symptoms the first being having physical symptoms of anxiety or fear the second unrealistic anxiety or cognitive distress third escape or avoidance behaviors anxiety disorders can described in the following three components biological some of the symptoms can be having racing heart rate increased blood pressure or muscle tension what we normally think of as stress or nausea for example psychological component worrying that's out of proportion to the situation generalized anxiety that gets in the way of one's normal functioning social component fear or being afraid to be around other people and other impairments in various social situations I I imagine that people are watching me they're watching me stumble in my efforts to articulate and typically I am very articulate but in that setting I can be almost rendered mute schizophrenia so severe psychological disorder that can be described by a person who has disorganized thinking perceive things differently and behave differently in terms of the biological component a person may have lowered or diminished facial expression or sometimes their facial expressions might seem frozen they may speak in a very monotone vocal tone or a monotone voice and some of their physical movements or gestures might be repetitive and unusual psychological component a person makes great delusions which are at which means at normal thinking or beliefs about something hallucinations which means seeing or hearing things that they normally shouldn't be seeing or hearing paranoid thinking thinking about things that actually aren't real disorganized thoughts and speech patterns where it's hard to connect the dots from topic to topic B to topic C social component imperative ility to identify emotional states of other people that if they have a difficult time reading other people's emotions and all the times for themselves they may show inappropriate emotional responses sometimes the lack of emotional exposes which is often called flat affect hmm paranoid schizophrenia okay and can you tell me what are some of the symptoms of paranoid schizophrenia that you are suffering from I chose when I hear voices in my head okay Oh what kind of voices are they can you tell me about the boys Nora I have all kinds of companion some fictional and some non-fiction I had lost our contact with reality why not take my medication I kind of lose contact with reality in what way I mean I said I I started I started having delusional thinking autism spectrum disorder this is a group of disorders consisting of autism Asperger syndrome and other developmental disorders combinations and severity of symptoms vary amongst individuals the biological component person may experience abnormal neurological development or sensitivity unusual reactions of sounds smells tastes or sights psychological component repetitive or obsessive behaviors inflexible adherence to routines or rituals social component impairment using spoken and nonverbal communication meaning that they do not speak and use hand gestures the way most people might impaired ability to understand other people's feelings so in this case they would have a difficult time reading what other people are expressing emotionally you don't know what what what they what they're really capable of mm-hm and they just they continuously surprise you mm-hm right you weren't sure he'd ever talk it now we've been talking yeah I don't know if you'll be able to learn more yeah p.m. you know does he can work the DVD player better than I you know I can in his head he didn't win he knows how to he bring about all that stuff out to them so he's able to entertain as well but you distant you know you never know expect him to float and it's just very difficult in you something that people have to go through a crossing when they hear the diagnosis pillows and watch people understand it mm-hm they just assume yeah well you know what you know what it is they'll deal with it miss month it's not that easy moving on to research methods I notice what you've been waiting for this entire lecture huh the scientific approach focuses on four general objectives description explanation prediction and control there is a great little exercise to help with the identification of these four major objectives on page 21 of your textbooks I suggest you take a look at it carefully there are four steps of the scientific method formulating a research question framing the research question in the form of a hypothesis testing the hypothesis and drawing conclusions about the correctness of the hypothesis in many textbooks they'll also describe a fifth step reporting the results the significant results of your studies to form their research question scientists look at previous research observations and current theories of behavior that may support their question next they form the question into a hypothesis a hypothesis is often referred to as an educated guess with guests being the dominant word heard a hypothesis it's not just a guess a hypothesis is a guess that you have based on previous scientific research because of the previous research you expect your own research to turn out in a certain way this being your hypothesis next is a test the hypothesis scientifically this means using different variables independent variables dependent variables criterion variables predictor variables and eliminating other causes or variables for the behavior studied lastly Sciences then draw conclusions about the hypothesis after analyzing the data obtained from testing the hypothesis psychologists follow the ethical principles that govern research with human and non-human subjects two of the key ethical provisions guiding research with human participants are informed consent and confidentiality informed consent requires that people be free to choose whether to participate in research studies they are also informed that they are allowed to withdraw whatever they want they are given sufficient information in advance about the study methods what they will be asked to do and any risks that may be involved this way they are given enough information to choose if they want to participate or not research participants also have a right to their own privacy they expect their identities not to be revealed and researchers are required to protect their confidentiality by keeping records of their participation participation secure and not disclosing their identities to others research samples need to be representative of the target population the naturalistic observation method allows scientists to measure behavior under naturally occurring conditions it is incredibly important to be unobtrusive or not interfere with the participants or subject however if a person or subject notices a researcher is observing them it is highly likely that they will begin to act different think about it don't you add different when you know people are watching well are you do in most situations this type of research reveals how people or animals behave but it does not reveal as to why they behave the way they do they determine why you must use controlled experiments correlational research explores relationship between variables which may help predict future behavior and suggest possible underlying causes of behavior but correlational research does not directly test cause-and-effect relationships longitudinal research is a type of correlational design that involves the study of selected subjects at periodic intervals over long periods sometimes spanning decades and the experimental method the investigator directly controls or manipulates the independent variable under controlled conditions in order to demonstrate cause-and-effect relationships they incorporate independent variables or IVs and dependent variables or DBS they use these variables to test their hypotheses IVs are factors that under the control and manipulated by the experimenter DBS are factors that are observed in order to determine the effects of manipulating the independent variables they are measured not manipulated and experiments participants are exposed to the IV then they are observed to see if the IV makes a difference in their behavior more precisely to see if the IV affects the DV the book uses a great example of alcoholic and non-alcoholic drinks the IV would be the type of beverage and the investigators observe if the and act more aggressively when drinking alcohol aggressiveness would be the divi the next slide shows a further breakdown on the differences of IVs and DBS in the experimental method the investigator directly controls or manipulates the independent variable under controlled conditions in order to demonstrate cause-and-effect relationships experiments uses random assignments as the basis for determining which subjects the experimental subjects receive an experimental treatment and which others called control subjects do not if random selection isn't you there is a high chance of selection factor this meaning that the cause of change in the behavior is not due to the IV but the type of participants instead as researchers we must avoid this to happen researchers use various methods including single blind placebo control studies double-blind placebo control studies and attention placebo control studies to attempt to control four subjects and researchers expectations experiments are evaluated in terms of their experimental validity internal validity refers to the ability of an experimental study to justify a cause-and-effect relationship between the independent and dependent variables internally balanced studies controlled for possible compounds or rival hypotheses expert ability refers to degree to which experimental results can be generalized to other subjects settings and even times construct military reverses agreed to which treatment effects can be accounted for by the theoretical mechanisms or constructs that are represented by the independent variables the epidemiological method examines the rate of occurrence of abnormal behavior in various halation population groups or settings evidence of houses orders cluster and certain groups or geographic areas may reveal underlying causes epidemiological researchers may use surveys and questionnaires as their preferred method of study they investigate the incidence of the behavior the prevalence of the behavior all while using random samples of participants to complete the surveys kinship studies attempt to disentangle the contribution of environment and heredity this would be twin studies and adoptive studies if a monozygotic or identical twins are born and one develops schizophrenia will the other if they are separated at Birth by adoption and one develops schizophrenia does the other even though they grow up with no contact from one another there is a 50% chance that the other identical twin does which is shown using kinship studies case study methods can provide a richness of clinical material but they are limited by difficulties of obtaining accurate and unbiased client histories by possible therapist biases and by the lack of control groups single case experimental designs are intended to help researchers overcome some of the limitations of the case study method and this wraps up the first lecture for abnormal psychology I hope you enjoyed it and I will see y'all in class [Music] [Music] you [Music]