Hello and welcome to Module 5, schizophrenia spectrum disorders. This is Lecture 1, introduction to schizophrenia. Schizophrenia is a psychological disorder that was formally identified and described in 1899 by a German psychiatrist named Emil Kraepelin, who referred to it as dementia praecox. In 1908, Kraeplin's colleague Eugen Bleuler first used the term schizophrenia, blending the Greek words for split and mind. Bleuler believed the essence of this disorder is the inability to associate one thought to another thought in a way we would consider logical and understandable. Bleuler believed all people with schizophrenia experience this breakdown and logical thinking, and that this breakdown could lead to many disparate symptoms, both across people within this disorder as well as within a single person. It's been well over a hundred years since Kraepelin and Bleuler formally identified schizophrenia and attempted to describe its presentation and origins. Today, as in the early 1900s, this illness remains a challenging one to describe and understand. As the early scientists observed, schizophrenia can look very different from person to person. But it always involves significant impairment in the ability to think, feel, and function in daily life. Now let's take a closer look at the symptoms of schizophrenia. Researchers and practitioners distinguish three major domains of symptoms: positive symptoms, negative symptoms, and disorganized symptoms. Let's look at each domain and the groups of symptoms included in them. First, we will discuss the positive symptoms. It's important to note the term positive does not mean the symptoms are enjoyable or good for the person, instead, the term indicates the presence of experiences and symptoms that are absent under normal circumstances, meaning people with schizophrenia have experiences that people who do not have this disorder do not have. Delusions are one such symptom. A delusion is a strong idea or belief that is no basis, in fact, a reality. A person with schizophrenia may have only one delusion or they may have many delusions. There are several subtypes of delusions. A person with a delusion of grandeur believes they are somehow famous or powerful. People with delusions of control believe their thoughts and feelings are being controlled by other people. People with delusions of reference believe that minor everyday objects or events hold special meaning and importance specifically for them. For example, a person with a delusion of reference may believe that every time they hear a particular song, they're receiving a direct message from God to contact a past romantic partner. Persecutory delusions are the most common type of delusion seen in schizophrenia. People with persecutory delusions believe they're being spied on, followed, threatened, harmed, or otherwise victimized by others. Hallucinations are perceptual problems in which people have sensory experiences that are not based in any actual environmental stimuli. The most common are auditory hallucinations. Approximately 70 percent of people with schizophrenia report experiencing auditory hallucinations. Most of the time, auditory hallucinations take the form of voices that narrate or comment on the person's activities, criticize the person's character or behavior, or tell the person to do things. When the voices give the person directions, they're referred to as command hallucinations. Biological research into this phenomenon suggests that while a person is hallucinating, an area of the brain called Broca's area is particularly active. This is an interesting finding because Broca's area is responsible for speech production, not speech comprehension. This research indicates a person with auditory hallucinations is actually listening to their own thoughts, but is unable to recognize them as their own. Hallucinations can involve other senses as well. While less common, people with schizophrenia experience visual hallucinations, such as colors, clouds, or even distinct objects or people. They may experience tactile hallucinations such as tingling, burning, or electric shock sensations in their skin. Somatic hallucinations involve the feeling there's something wrong or bizarre happening inside the body, such as feeling an army of ants marching through the blood vessels. Gustatory hallucinations involve the experience that food and drink tastes strange or different. Finally, olfactory hallucinations involves smelling things that no one else can smell, like smoke or rotten eggs. Most of the time, hallucinations and delusions occur together in a person with schizophrenia. They often relate to each other as the person tries to make sense of what's happening to them. For instance, a person who hears voices whispering in the walls, an auditory hallucination, may believe her neighbors are spying on her, a persecutory delusion. The next domain is referred to as negative symptoms. While positive symptoms are the presence of an experience that's normally absent, negative symptoms refer to the absence of experiences that are normally present. Let's take a closer look. All of the negative symptoms begin with the prefix A, which means without. Avolition is an inability to initiate and complete tasks, activities, or other behavior. A person with avolition may appear uninterested or unable to perform even the most fundamental daily activities, such as attending to their personal hygiene. Alogia refers to a lack of speech. People with this symptom demonstrate significantly decreased speech production. They rarely initiate speech, and they respond to questions with very brief, unembellished answers. They may also demonstrate a significantly delayed response time as if they're struggling to find the words and put them together. Alogia is also called poverty of speech. Anhedonia is a lack of pleasure, joy, enjoyment, and other positive emotions. People with this symptom appear to experience very few, if any emotions, and are often described as having restricted, blunted, or flat affect. In this context, affect refers to the emotions a person shows in their facial expression, tonal voice, and overall demeanor. While people with anhedonia demonstrate little to no emotional experience, research indicates that they in fact, feel a full range of emotions internally, but they're unable to express the emotions outwardly. Asociality refers to a lack of interest in interpersonal connections, relationships, and activities. Someone with this symptom withdraws from the social world of family, friends, and other relationships and may appear preoccupied with what is happening in their minds, for example, their hallucinations and delusions. Withdrawal firm relationships tends to worsen other symptoms, because without other people to provide feedback about what is real and what is not real, and what behavior is considered normal and what is not, the person can retreat further into their world of hallucinations and delusions. Asociality is also related to a loss of social skills, including the ability to understand how other people are feeling and what they need or want. The third domain of schizophrenia is disorganized symptoms. This grouping includes a variety of symptoms affecting speech, emotions, and behavior. Disorganized speech indicates a serious difficulty with thinking clearly and forming logical thoughts. People with disorganized speech may jump from topic to topic with no apparent logical thread connecting them. This is referred to as loose associations or thought derailment. Tangential speech occurs when instead of answering the question that's asked, the person speaks at length about an unrelated topic. Disorganized emotions take the form of inappropriate affect. That is, someone with this symptom may suddenly laugh or cry uncontrollably in socially inappropriate situations and without any apparent trigger. It's possible that episodes of disorganized emotion indicate the person is having a strong emotional response to something that's happening internally, for example, they're responding to an auditory hallucination. Disorganized behavior can take many forms. Behavior may appear unusual or even bizarre, such as making repetitive, awkward movements, unusual facial expressions, or odd gestures. Catatonia is a term that refers to particular forms of unusual movements. A person in a catatonic stupor remains totally motionless and silent for long periods of time. A person experiencing catatonic rigidity maintains a rigid upright posture for similarly long periods of time and may resist the efforts of others to help them move. A person with catatonic posturing assumes unusual or bizarre body positions and holds those positions in place without moving. Finally, a person experiencing catatonic excitement moves around in a state of excitement or agitation, often waving their arms or legs. By now, it should be clear that schizophrenia contains a large number of disparate symptoms. Two people diagnosed with schizophrenia may manifest the disorder very differently. For example, while one person may struggle primarily with hallucinations and delusions, for another person, negative symptoms and catatonia may be most apparent. Schizophrenia is a complex disorder. Even though it has been formally recognized and described by clinicians and researchers for well over 100 years, it remains a challenging disorder to understand and effectively treat. In our next lecture, we will talk about the prevalence and impact of schizophrenia, as well as look briefly at other disorders that share similar features to schizophrenia and are considered parts of the schizophrenia spectrum.
