Chaper 2: An Integrative Approach to Psychopathology

• One-dimensional models


  Attempt to trace behavior to a single cause
• Multidimensional models


  Acknowledge multiple influences from biology, psychology, and social factors
• One-dimensional models explain behavior in terms of a single cause
• One-dimensional models could refer to a paradigm, school, or conceptual approach
• One-dimensional models tend to overlook information from other areas
• Multidimensional models


  • Interdisciplinary, eclectic, and integrative
  • Considers a 'system' of influences causing and maintaining suffering
  • Draws upon information from various sources
  • Acknowledges that abnormal behavior results from multiple influences
• Major influences on abnormal behavior

  • Biological
  • Behavioral
  • Emotional
  • Social and cultural
  • Developmental
  • Environmental
• Polygenetic


  Multiple genes
• Genes typically account for less than 50% of variations in psychopathology
• Diathesis stress model


  Disorders result from underlying risk factors combining with life stressors
• Gene-environment correlation model/reciprocal-gene environment model


  Outcomes result from interactions between genetic vulnerabilities and experience
• Genetics may influence individuals to seek out certain environments, affecting their experiences
• Gene expression and gene-environment interactions are vital in understanding psychopathology
• Epigenetic mechanisms


  Changes in gene expression without altering DNA sequences
• Environmental factors can influence gene expression and contribute to the development of psychological disorders
• Neuroscience


  Focuses on the role of the nervous system in disease and behavior
• Components of the nervous system

  • Neurotransmitters
  • CNS (brain and spinal cord)
  • PNS
• Endocrine system


  Regulates hormone release
• Hypothalamic-pituitary-adrenocortical axis (HPA axis)


  Integrates endocrine and nervous system function
• Dysregulated hormones implicated in some forms of psychopathology
• Main types of neurotransmitters

  • Serotonin
  • Glutamate
  • GABA
  • Noradrenaline
  • Dopamine
• Neurotransmitters


  Molecules responsible for signal transduction between neurons and between neurons and end-organ or target tissue
• Neurotransmitters mediate communication within the nervous system
• Neurotransmitters form paths from one part of the brain to another
• Neurons sensitive to specific neurotransmitters cluster together and form distinct paths
• Neurotransmitter systems are often anatomically localizable, with distinct nuclei and fiber tracts
• More than a hundred different neurotransmitters function in various parts of the nervous system and body
• New neurotransmitters are frequently discovered, and existing systems undergo revisions
• Examples of neurotransmitters


  • Serotonin
  • Dopamine
  • Acetylcholine
  • Glutamate
• Abnormalities in serotonin are associated with depression, while dopamine abnormalities are implicated in schizophrenia
• Changes in neurotransmitter activity can make individuals more or less likely to exhibit certain behaviors
• Broad-based disturbances often involve interactions between various neurotransmitter systems rather than alterations in a single system
• Mechanisms of studying neurotransmitter function

  • Introducing agonists, antagonists, or inverse agonists to influence neurotransmitter activity
  • Interfering with neurotransmitter production, release, reuptake, or metabolic breakdown
• Most antidepressants interfere with neurotransmitter availability in the synaptic cleft by inhibiting reuptake or metabolic breakdown
• Classic neurotransmitters relevant to psychopathology

  • Monoamines (serotonin, dopamine, noradrenaline, histamine)
  • Amino acids (GABA, glutamate)
  • Acetylcholine
• Autoreceptors


  Receptors on releasing cells involved in feedback systems and autoregulation
• Glutamate


  Excitatory neurotransmitter
• GABA


  Inhibitory neurotransmitter
• Serotonin


  Regulates mood, behavior, and thought processes
• Noradrenaline


  Plays a role in stress response, arousal, and anxiety