INDIVIDUAL DIFFERENCES AND DEVELOPMENTAL PSYCHOLOGY IN MENTAL HEALTH

INTRODUCTION

This section requires you to explore how personality factors and the nature vs. nurture debate interact in the context of mental disorders. Here's how to approach it:

1. Individual Differences: Personality and Mental Disorders

• What it means: People vary in their traits and behaviours, which influence their susceptibility to mental disorders. Theories like Eysenck’s Personality Theory and the Five-Factor Model (Big Five) are particularly relevant here.

Example:

• Eysenck’s Theory: High scores in neuroticism (emotional instability) have been linked to anxiety disorders, while high psychoticism is associated with risk-taking behaviours and potential links to schizophrenia.

• Five-Factor Model: High neuroticism may predict vulnerability to depression, while low extraversion (introversion) might contribute to social withdrawal seen in conditions like social anxiety.

How individual differences relate to mental disorders:

• Schizophrenia: Individual personality traits like high openness to experience may correlate with unusual or creative thinking, a characteristic sometimes seen in prodromal phases of schizophrenia.

• Depression: Neuroticism can make someone more sensitive to negative events, increasing their risk for depressive episodes.

2. Developmental Psychology: Nature vs. Nurture in Mental Disorders

• What it means: This requires exploring how genetic (biological) and environmental (social/experiential) factors influence the development of mental disorders.

Example:

• Schizophrenia:

  • Nature (genetic factors): Twin and adoption studies show heritability rates of about 80%. Specific genes like COMT and DISC1 are linked to increased risk.

  • Nurture (environmental factors): Stressful life events, prenatal exposure to viruses, or urban living conditions can act as triggers in individuals predisposed to schizophrenia.

How Developmental Psychology Fits In:

• Impact on life stages: Schizophrenia often develops in late adolescence or early adulthood. Developmental stages influence when vulnerabilities appear. For example, excessive synaptic pruning during adolescence might explain cognitive deficits in schizophrenia.

• Critical periods: Childhood abuse or neglect can disrupt brain development, increasing susceptibility to disorders like borderline personality disorder (BPD).

5.1.6 DEVELOPMENTAL PSYCHOLOGY: GENES AND MENTAL HEALTH

Genes and Biochemical Explanations

This focuses on how genetic and biochemical factors influence mental health and development.

1. Genetic Explanations for Mental Disorders

   • Mental disorders often have a genetic component that interacts with environmental triggers.

   • Example: Schizophrenia is associated with multiple genetic loci, but the environment (e.g., stress or drug use) may determine whether these genes are expressed (epigenetics).

2. Biochemical Explanations for Schizophrenia

   • Schizophrenia is linked to:

     • Dopamine Hypothesis: Overactivity in dopamine pathways (especially in the mesolimbic system) causes positive symptoms (e.g., hallucinations).

     • Glutamate Hypothesis: Low glutamate levels are associated with cognitive deficits and negative symptoms.

   • Developmental effects:

     • Biochemical imbalances in adolescence may disrupt neural pathways, leading to the onset of symptoms during critical developmental periods.

Key Developmental Implications

• Prenatal Development:

  • Genetic predispositions may lead to structural brain abnormalities, such as enlarged ventricles in individuals with schizophrenia.

  • Exposure to teratogens (e.g., maternal infections like rubella) during pregnancy increases risk.

• Adolescent Brain Development:

  • Adolescence is a period of significant brain development, with processes like synaptic pruning. Overactive pruning in those with genetic predispositions might trigger schizophrenia.

TIPS FOR APPLYING THESE CONCEPTS

• Use studies to back up your explanations:

  • Tienari et al. (2004): Found that adopted children with biological parents who had schizophrenia were more likely to develop the disorder, especially if raised in a dysfunctional family environment.

  • Caspi et al. (2003): Found that individuals with the short allele of the serotonin transporter gene (5-HTT) were more likely to develop depression when exposed to stressful life events.

• Integrate Nature and Nurture:

  • Explain how genetic predispositions (nature) can be influenced by environmental factors (nurture) in shaping mental health outcomes.

• Examples of Developmental Stages:

  • Explore how disorders manifest at different life stages and how genetic or environmental influences vary across these stages.

Would you like further clarification or examples? I can help tailor these points to fit specific lessons or student needs!