01 · Explore
Defining Abnormality: The Four Ds
Psychology distinguishes between normal and abnormal behaviour by examining how a person adapts to life's challenges. While no single definition is universally accepted, psychologists often use the 'Four Ds' as a framework for identification.
Abnormality is often defined through four criteria: Deviance, Distress, Dysfunction, and Danger. Deviance refers to behaviours, thoughts, or emotions that differ markedly from societal norms. Distress involves the unpleasant and upsetting feelings experienced by the individual or those around them. Dysfunction occurs when the behaviour interferes with daily constructive activities, such as work or maintaining relationships. Danger implies that the behaviour may pose a risk to the individual or others.
There are two primary approaches to defining abnormality. The first views it as a deviation from social norms—rules for proper conduct established by a culture's history and values. For instance, aggressive behaviour might be accepted in a competitive culture but viewed as abnormal in one that values cooperation. The second approach focuses on maladaptive behaviour, which hinders an individual's well-being, growth, and self-actualisation. Under this view, even conforming behaviour can be abnormal if it prevents a person from reaching their potential.
The study of these maladaptive behaviours, including their causes and treatments, is known as Abnormal Psychology. It is important to view psychological disorders as failures in adaptation to life challenges rather than something to be ashamed of. Stigma often prevents individuals from seeking help, but mental illness should be understood as any other medical condition.
| Criterion | Description |
|---|---|
| Deviance | Extreme or unusual behaviour that breaks societal norms. |
| Distress | Upsetting and unpleasant emotional states for the person. |
| Dysfunction | Interference with the ability to perform daily tasks. |
| Danger | Potential harm to self or others. |
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How does the maladaptive approach differ from the social norms approach in defining abnormality?
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02 · Explore
Historical Background of Psychological Disorders
Throughout history, the understanding of mental illness has shifted between supernatural, biological, and psychological explanations.
Ancient theories often attributed abnormal behaviour to supernatural forces like evil spirits or demons. Treatments included exorcism, prayers, or seeking help from a shaman (medicine man). In contrast, the biological or organic approach, rooted in ancient Greece with physicians like Hippocrates and Plato, suggested that disorders arise from physical imbalances. Hippocrates and later Galen proposed the theory of four humours (blood, black bile, yellow bile, and phlegm), where imbalances caused different temperaments—a concept similar to the Indian Vata, Pitta, and Kapha doshas.
During the Middle Ages, superstition returned, leading to demonology and witch-hunts. However, the Renaissance saw a rise in humanism, with Johann Weyer arguing that 'witches' were actually mentally disturbed individuals needing medical care. The 17th and 18th centuries, known as the Age of Enlightenment, replaced dogma with scientific methods. This led to the Reform Movement, which improved asylum conditions and introduced deinstitutionalisation, focusing on community care for recovered individuals.
Today, modern psychology uses a bio-psycho-social approach. This interactional perspective acknowledges that biological, psychological, and social factors all play critical roles in the development and outcome of psychological disorders.
Evolution of Perspectives on Abnormality
- 1
Supernatural
Belief in evil spirits and demons; treated with exorcism.
- 2
Biological
Focus on body fluids (humours) and brain processes.
- 3
Psychological
Focus on inadequacies in thinking, feeling, and perceiving.
- 4
Bio-Psycho-Social
Modern convergence of biological, psychological, and social factors.
The historical progression of how societies have viewed and explained the causes of abnormal behaviour.
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What was the significance of the Reform Movement in the 18th century?
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03 · Explore
Factors and Models Underlying Abnormal Behaviour
Psychologists use various models to explain why disorders develop, ranging from genetic predispositions to learned behaviours and social labels.
The biological model posits that disorders have biochemical or physiological bases. Research links specific neurotransmitters to disorders: low GABA activity is associated with anxiety, excess dopamine with schizophrenia, and low serotonin with depression. Genetic factors also play a role, though usually, multiple genes combine to create a vulnerability rather than a single 'culprit' gene.
Psychological models include the psychodynamic model (unconscious conflicts between id, ego, and superego), the behavioural model (maladaptive learning through conditioning), and the cognitive model (irrational assumptions and illogical thinking). The humanistic-existential model emphasizes the natural drive toward self-actualisation and the responsibility to give meaning to one's life.
The socio-cultural model examines how social forces, such as family structure, social networks, and societal labels, influence behaviour. Finally, the Diathesis-Stress Model is a widely accepted synthesis. it suggests that a disorder develops when a biological predisposition (diathesis) is triggered by environmental stressors. A person 'at risk' may only develop a disorder if exposed to specific pathogenic stressors.
| Model | Core Explanation of Abnormality |
|---|---|
| Biological | Biochemical imbalances or genetic predispositions. |
| Psychodynamic | Unconscious conflicts originating in early childhood. |
| Behavioural | Learning maladaptive responses through conditioning. |
| Cognitive | Irrational beliefs and illogical thought patterns. |
| Socio-cultural | Impact of social roles, labels, and family systems. |
| Diathesis-Stress | Biological vulnerability triggered by environmental stress. |
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According to the biological model, which neurotransmitter is linked to schizophrenia?
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04 · Explore
Anxiety and Related Disorders
Anxiety disorders are the most common category of psychological disorders, characterized by intense, distressing, and dysfunctional fear or apprehension.
Generalised Anxiety Disorder (GAD) involves prolonged, vague, and intense fears not attached to a specific object, often accompanied by motor tension and hypervigilance. Panic Disorder is marked by recurrent, unpredictable panic attacks—abrupt surges of intense terror with physical symptoms like breathlessness, palpitations, and a fear of dying. Separation Anxiety Disorder (SAD) involves extreme distress regarding separation from attachment figures, often seen in children who cling to parents and fear being alone.
Phobias are irrational fears of specific objects or situations. These include Specific Phobias (e.g., fear of animals or enclosed spaces), Social Anxiety Disorder (intense fear of being judged by others), and Agoraphobia (fear of entering unfamiliar situations or leaving home).
Obsessive-Compulsive Disorder (OCD) involves obsessions (unpleasant, persistent thoughts) and compulsions (the need to perform repetitive acts like washing or checking). Related disorders include hoarding and hair-pulling. Post-Traumatic Stress Disorder (PTSD) occurs after natural disasters or violence, manifesting as flashbacks, nightmares, and emotional numbing. Other disorders in this category include Selective Mutism, Substance/Medication-Induced Anxiety Disorder, and Anxiety Disorder Due to Another Medical Condition.
| Disorder | Key Symptoms |
|---|---|
| GAD | Vague, unexplained intense fear; inability to relax. |
| Panic Disorder | Sudden intense terror; palpitations; dizziness. |
| Specific Phobia | Irrational fear of a particular object or animal. |
| OCD | Inability to stop certain thoughts or repetitive acts. |
| PTSD | Flashbacks and emotional numbing after trauma. |
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What is the difference between an obsession and a compulsion in OCD?
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05 · Explore
Somatic Symptom and Dissociative Disorders
These disorders involve physical complaints without biological causes or a severance of the connection between ideas and emotions.
Somatic Symptom Disorder involves persistent body-related symptoms that cause significant distress, even if no serious medical condition exists. In Illness Anxiety Disorder, the primary concern is the anxiety about developing a serious disease, despite having no or mild symptoms. Conversion Disorder is characterized by the sudden loss of a body function, such as paralysis or blindness, typically following a stressful experience.
Dissociative Disorders involve a sudden alteration of consciousness or identity. Dissociative Amnesia is selective memory loss with no organic cause, sometimes including 'fugue' (unexpected travel and assumption of a new identity). Dissociative Identity Disorder (DID), formerly multiple personality, involves a person assuming two or more distinct personalities. Depersonalisation/Derealisation Disorder involves a dreamlike state where the person feels separated from themselves or reality.
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How does Somatic Symptom Disorder differ from Illness Anxiety Disorder?
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06 · Explore
Depressive and Bipolar Disorders
Mood disorders involve severe disturbances in emotional state, ranging from the lows of depression to the highs of mania.
Major Depressive Disorder is characterized by a prolonged period of depressed mood, loss of interest in activities, sleep problems, tiredness, and thoughts of death. Risk factors include genetics, age (young adulthood for women, early middle age for men), and lack of social support. Bipolar I Disorder involves alternating periods of mania (extreme highs) and depression. Other examples of bipolar and related disorders include Bipolar II Disorder and Cyclothymic Disorder.
Suicide is a serious outcome of complex biological, psychological, and social factors. It is often linked to difficulties in problem-solving and emotional expression. Suicides are preventable through multi-sectoral approaches. Measures suggested by the WHO include limiting access to the means of suicide, responsible media reporting, bringing in alcohol-related policies, early identification and treatment of people at risk, training health workers in assessment, and providing community support. Strengthening self-esteem by accentuating positive life experiences and establishing trustful communication is vital for prevention.
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What are some behavioral signs that a student might be in distress and at risk?
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07 · Explore
Schizophrenia Spectrum Disorders
Schizophrenia is a debilitating psychotic disorder where personal and social functioning deteriorate due to disturbed thought and perception.
Symptoms are grouped into three categories. Positive symptoms are 'pathological excesses,' such as delusions and hallucinations. Delusions are false beliefs held on inadequate grounds; common types include delusions of persecution (being plotted against), delusions of reference (attaching personal meaning to others' actions), delusions of grandeur (believing one is specially empowered), and delusions of control (believing thoughts/actions are controlled by others). Hallucinations are perceptions without external stimuli; while auditory are most common, they can also be tactile (tingling/burning), somatic (internal sensations), visual, gustatory (taste), or olfactory (smell).
Formal thought disorders make communication difficult and include derailment (loosening of associations), neologisms (inventing new words), and perseveration (inappropriate repetition of thoughts). Negative symptoms are 'pathological deficits,' including alogia (poverty of speech), blunted or flat affect (lack of emotional expression), and avolition (inability to start or complete tasks). Psychomotor symptoms involve physical abnormalities, such as catatonia, where a person may remain in a catatonic stupor (motionless), catatonic rigidity (upright posture), or catatonic posturing (awkward positions).
| Symptom Type | Examples |
|---|---|
| Positive | Delusions, Hallucinations, Inappropriate Affect. |
| Negative | Alogia, Flat Affect, Social Withdrawal, Avolition. |
| Psychomotor | Catatonic Stupor, Rigidity, or Posturing. |
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What is a 'delusion of persecution'?
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08 · Explore
Neurodevelopmental and Childhood Disorders
These disorders manifest early in development, often before a child enters school, and hamper social and academic functioning.
Attention-Deficit/Hyperactivity Disorder (ADHD) features inattention (difficulty concentrating) and hyperactivity-impulsivity (constant motion and inability to wait). Autism Spectrum Disorder involves profound difficulties in social interaction and communication, along with restricted, repetitive patterns of behaviour. These patterns may include self-stimulatory motor movements like hand flapping or self-injurious behaviours such as head banging. Intellectual Disability is defined by an IQ below 70 and deficits in adaptive behaviour manifested before age 18.
Specific Learning Disorder involves difficulty processing information accurately, leading to performance below average in reading, writing, or math. Disruptive disorders include Oppositional Defiant Disorder (ODD), characterized by stubbornness and hostility, and Conduct Disorder, which involves violating societal norms and the rights of others through aggression or theft.
| Disorder | Primary Characteristics |
|---|---|
| ADHD | Inattention, impulsivity, and constant motion. |
| Autism | Impaired social interaction; repetitive behaviours. |
| Intellectual Disability | IQ below 70; deficits in self-care and social skills. |
| ODD | Hostility and defiance toward authority figures. |
| Conduct Disorder | Aggression; violation of property and rules. |
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What are the two main features of ADHD?
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09 · Explore
Feeding, Eating, and Substance-Related Disorders
These disorders involve maladaptive behaviours related to consumption, whether of food or addictive substances.
Eating disorders include Anorexia Nervosa (distorted body image leading to self-starvation), Bulimia Nervosa (binge eating followed by purging), and Binge Eating Disorder (out-of-control eating without purging). These are often driven by societal standards of attractiveness.
Substance-Related and Addictive Disorders involve the maladaptive use of substances like alcohol, cocaine, tobacco, and opioids (including morphine, heroin, and cough syrup). Alcohol acts as a depressant on the central nervous system, impairing judgment and motor coordination. Long-term abuse leads to tolerance (needing more for the same effect) and withdrawal symptoms. Heroin abuse poses a high risk of fatal overdose by paralyzing the brain's respiratory centers, while cocaine abuse can lead to patterns of intoxication that dominate a person's social and professional life.
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How does Anorexia Nervosa differ from Bulimia Nervosa?
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