Schizophrenia

Schizophrenia

Chronic psychotic disorder characterized by disturbances in thought, perception, emotion, and behavior.

Mental Disorder

Syndrome involving significant disturbances in cognition, emotion regulation, or behavior causing distress or impairment.

Psychosis

Loss of contact with reality characterized by hallucinations and/or delusions.

Neurodevelopmental Disorder

Disorder resulting from abnormal brain development affecting neural connectivity.

Synaptic Connectivity

Pattern of communication between neurons; altered in schizophrenia.

Positive Symptoms

Excesses or distortions of normal function such as hallucinations and delusions.

Negative Symptoms

Loss or reduction of normal functions such as flat affect, reduced motivation, and social withdrawal.

Cognitive Symptoms

Impairments in attention, working memory, executive function, and decision-making.

Hallucination

Perception occurring without an external stimulus; auditory hallucinations are most common.

Delusion

False fixed belief maintained despite contradictory evidence.

Persecutory Delusion

Belief that others are trying to harm, spy on, or persecute the individual.

Grandiose Delusion

Belief of having exceptional power, talent, or importance.

Delusion of Reference

Belief that unrelated events or messages are personally directed toward oneself.

Delusion of Control

Belief that one's thoughts or actions are controlled by external forces.

Identity Delusion

Belief that one is another person or famous figure.

Guilt Delusion

False belief of having committed a terrible wrongdoing.

Disorganized Thinking

Impaired logical organization of thoughts.

Loose Associations

Thoughts shift illogically from one idea to another.

Disorganized Speech

Speech that is difficult to follow because of disorganized thinking.

Catatonia

Marked disturbance in movement or behavior ranging from immobility to excessive activity.

Flat Affect

Reduced emotional expression.

Avolition

Lack of motivation to initiate or complete goal-directed activities.

Social Withdrawal

Reduced interest in social relationships.

Anhedonia

Inability to experience pleasure.

Executive Function

Higher cognitive abilities including planning, inhibition, and problem-solving.

Working Memory

Ability to temporarily store and manipulate information.

Dopamine Hypothesis

Theory that abnormal dopamine signaling contributes to schizophrenia.

Mesolimbic Pathway

Dopamine pathway associated with positive symptoms when overactive.

Mesocortical Pathway

Dopamine pathway associated with negative and cognitive symptoms when underactive.

Nigrostriatal Pathway

Dopamine pathway involved in movement control.

Tuberoinfundibular Pathway

Dopamine pathway regulating prolactin release.

Ventral Tegmental Area (VTA

Origin of mesolimbic and mesocortical dopamine pathways.

Nucleus Accumbens

Reward-related brain region receiving mesolimbic dopamine projections.

Prefrontal Cortex

Brain region involved in executive functions and cognitive control.

Dorsolateral Prefrontal Cortex (DLPFC)

Brain region important for working memory and executive function; often hypoactive in schizophrenia.

Ventromedial Prefrontal Cortex (VMPFC)

Brain region involved in emotion regulation and decision-making.

Striatum

Brain region involved in movement and reward processing.

Thalamus

Relay center for sensory and motor information.

Substantia Nigra

Midbrain structure containing dopamine neurons involved in movement.

Glutamate Hypothesis

Theory suggesting NMDA receptor dysfunction contributes to schizophrenia.

Serotonin

Involved in mood regulation; altered serotonergic signaling contributes to symptoms.

Brain Chemical Imbalance

Imbalance involving dopamine, glutamate, and serotonin neurotransmission.

Genetic Risk

Family history significantly increases the likelihood of developing schizophrenia.

Environmental Factors

Stress, trauma, infections, malnutrition, and adverse childhood experiences increase risk.

Gene-Environment Interaction

Development of schizophrenia results from interactions between genetic susceptibility and environmental factors.

Twin Studies

Monozygotic twins show higher concordance than dizygotic twins, supporting genetic influence.

Prevalence

Schizophrenia affects approximately 1% of the general population.

Typical Age of Onset

Late adolescence to early adulthood.

Diagnosis

Requires at least two core symptoms for six months with significant impairment.

DSM Diagnostic Criteria

Hallucinations, delusions, disorganized speech, disorganized behavior/catatonia, or negative symptoms.

Antipsychotic Drugs

Primary pharmacological treatment for schizophrenia.

Typical Antipsychotics

First-generation D2 receptor antagonists that primarily reduce positive symptoms.

Atypical Antipsychotics

Second-generation drugs acting on dopamine and serotonin receptors with broader symptom control.

Haloperidol

Typical antipsychotic with strong D2 receptor blockade.

Chlorpromazine

First-generation antipsychotic of the phenothiazine class.

Clozapine

Atypical antipsychotic effective for treatment-resistant schizophrenia.

Risperidone

Atypical antipsychotic acting on dopamine and serotonin receptors.

Olanzapine

Atypical antipsychotic used to treat positive and negative symptoms.

Quetiapine

Atypical antipsychotic with dopamine and serotonin receptor activity.

Aripiprazole

Partial dopamine agonist classified as an atypical antipsychotic.

Psychotherapy

Supportive treatment used alongside medication.

Community Care

Approach emphasizing outpatient treatment and social support.

Institutional Care

Inpatient treatment for severe cases requiring intensive management.