Cognitive Biases, Developmental Stages & Clinical Psychology

Posted on Feb 5, 2026 in Psychology

Cognitive Heuristics and Biases

  • Availability Heuristic — Judging based on how easy it is to think of examples or occurrences.
  • Representativeness Heuristic — Judging based on how it resembles another event.
  • Numerosity Heuristic — Judging quantity/probability based on the number of pieces something has been divided into.
  • Anchor-and-Adjust Bias — Making a guess by anchoring and pivoting around a previous estimate; there is a bias toward under-correction.
  • Above-Average Effect — The finding that most people often think they are in the top half of all people for traits or skills they value.
  • Planning Fallacy — The tendency to believe you will finish a project or activity sooner than you actually do (underestimation of time).

Cognitive Development (Piaget)

  • Stage Theorists — Those who argue we undergo large psychological transformations at different ages in a set order (e.g., Piaget, Erikson).
  • Sensorimotor Stage — First stage of development (ages 0–2) when children learn to perceive the world and control their bodies.
    • Altricial — A term for species that begin life helpless and mature slowly.
    • Precocial — The opposite of altricial: species that mature quickly and begin life capable.
    • BOPP — Basic object permanence paradigm: involves hiding an object in an obvious way and seeing if an infant searches for it; tests object permanence.
    • Perseveration — Evidence that older infants may not completely understand object permanence and continue previously learned responses.
    • A-not-B Error — A child will look in the wrong spot due to being conditioned to look there even when the object is obviously placed in a different spot; an example of perseveration.
  • Preoperational Stage — Second stage of development (ages 2–6) when children can perform very basic forms of abstract thinking.
    • Egocentrism — The inability to see the world from the vantage point of others; a form of self-centeredness.
  • Concrete Operational Stage — Third stage of development (ages 6–11) when children can perform more complex mental operations but generally only manipulate concrete elements in front of them.
    • Conservation — The awareness that objects can change shape or appearance without changing mass or amount (e.g., splitting clay does not change the amount present).
    • Seriation — The ability to rank a set of objects by physical or psychological dimensions.
  • Formal Operational Stage — The fourth stage of development; begins in puberty and there is no longer a biological limit to the complexity of abstract thought.
    • Transitive Inferences — Drawing conclusions about rankings of things based on purely abstract information.
    • ACID — An acronym for four essential features of a formal operational thinker:
      • Abstraction — The ability to use symbols to represent and manipulate things (e.g., read a map, do math, read music).
      • Creativity — The ability to think in novel ways, combine ideas, or deconstruct concepts in new ways.
      • Induction — Reasoning from specific cases to a broad rule.
      • Deduction — Reasoning from a broad rule to a specific prediction.
    • Pragmatism — Recognizing that logic alone cannot solve some of life’s trickiest problems; critics say this may not fully develop until after adolescence.
  • Scaffolding — Adults help children by making difficult tasks more achievable; this can include offering hints or simplifying aspects of the task.

Lifespan Development (Erikson)

  • Psychosocial Theory — The eight-stage theory of how we develop emotionally and interpersonally.
  • Connectedness — The desire to be loved and accepted; one of two core motivational lenses.
  • Mastery — The desire to develop control over your life; the second core motivational lens.
  • Trust vs. Mistrust — The first stage of psychosocial development: helpless newborns and infants focus heavily on connectedness and whether they can trust caregivers.
    • Secure Attachment Style — Infants feel they can trust their caregivers and are easily soothed.
    • Insecure Attachment Style — Develops when infants feel they cannot rely on caregivers in times of distress.
      • Anxious-Ambivalent — Characterized by chronic worry about abandonment; children are difficult to soothe.
      • Anxious-Avoidant — Involves showing little distress when a caregiver disappears and a lack of interest when care is offered.
  • Hurdle Race Metaphor — An analogy: clearing early hurdles in life makes it easier to clear later ones.
  • Autonomy vs. Shame & Doubt — Ages 1–3: children figure out what they can and cannot do.
  • Initiative vs. Guilt — Ages 3–6: children pursue mastery and plan ahead, and may blame themselves if they think they have failed.
  • Industry vs. Inferiority — Ages 6–12: children seek mastery by developing complex skills (math, sports, music) and compare themselves to peers.
    • Social Comparison Theory — The idea that we determine our standing by checking performances against those of peers.
  • Identity vs. Role Confusion — Ages 12–18: teens begin to ponder who they are and what that means for their future.
  • Intimacy vs. Isolation — Ages 18–39: connectedness becomes crucial as young adults look for trusted partners and relationships.
  • Generativity vs. Self-Absorption — Ages 40–59: adults ask whether they are helping others and making a lasting contribution.
  • Ego Integrity vs. Despair — Ages 60+: older adults reflect on whether life has been worthwhile and place strong value on connectedness.

Clinical Disorders and Diagnoses

  • Psychiatrists — Medical doctors who specialize in diagnosing and treating clinical disorders; more focused on biology and medication.
  • DSM — Diagnostic and Statistical Manual of Mental Disorders: the official psychiatric resource for diagnosing hundreds of clinical disorders.
  • Three Key Features of Disorder — Psychological disorders typically require three elements to be considered a clinical disorder:
    • Disturbance — The person experiences extreme and unpleasant symptoms.
    • Impairment — Symptoms cause troubles that interfere with daily life.
    • Internal Dysfunction — Symptoms are stable and have a biological or dispositional basis, such as personality traits or deeply held attitudes.
  • Biopsychosocial Model — Disorders originate in biological, psychological, and social forces.
  • Clinical Depression — A disorder in which the person has a flat mood and/or lack of interest in normal activities along with at least four other symptoms for at least 14 consecutive days.
  • Bipolar I Disorder — A disorder involving lengthy and extreme mood swings, alternating between manic and depressive states for weeks or months.
  • Generalized Anxiety Disorder — A disorder characterized by chronic, debilitating, and unrealistic worries about many aspects of life.
  • Phobia — An irrational fear or worry of a specific object or situation (e.g., heights, spiders, enclosed spaces).
  • Anorexia Nervosa — An eating disorder involving severely restricted food intake, intense fear of weight gain despite low weight, and body dysphoria.
  • Bulimia Nervosa — An eating disorder in which people have extreme concerns about weight and engage in binge-eating and purging cycles.
  • Schizophrenia Spectrum — A set of disorders involving highly unusual, disorganized, or inappropriate thoughts and behaviors, including delusions, hallucinations, disorganized speech, or social withdrawal.
  • Dissociative Identity Disorder — A clinical disorder in which a person has two or more distinct identities, each with little or no awareness of the others.
  • Comorbidity — The co-occurrence of two or more clinical disorders in the same person.

Treatments for Clinical Disorders

  • Chemical Intervention — Drugs (psychotropic medications) that can reduce or eliminate symptoms of psychological disorders.
  • Psychotherapy — Professional therapeutic interactions between a patient and a trained clinician to reduce or eliminate clinical symptoms.
  • The Medical Model — The view that clinical disorders are medical illnesses that can be treated with drugs.
  • Concept Creep — A process where definitions of harmful behaviors expand, loosening criteria for labeling social problems or diagnosing psychological disorders over time.
  • Anxiolytic — An anxiety-reducing drug (e.g., Xanax or Valium).
  • New-generation Antidepressant — Drugs (often SSRIs) that can reduce depressive symptoms and tend to have fewer side effects than older antidepressants.
  • Second-generation Antipsychotics — Modern chemical interventions for schizophrenia that generally have fewer and less severe side effects than older antipsychotics.
  • Tardive Dyskinesia — Involuntary motor movements that can be a common side effect of antipsychotic medications.
  • Psychoanalysis — Freud’s idea that therapists help patients access and resolve unconscious conflicts, often rooted in childhood.
  • Transference — The psychoanalytic concept that patients displace feelings about significant others onto their therapists.
  • Resistance — Pushing back against a therapist’s suggested explanations for a patient’s difficulties.
  • Free Associations — A technique where patients report anything that comes to mind to uncover hidden urges and conflicts.
  • Repression — The process by which the ego or superego pushes an uncomfortable or inappropriate thought into the unconscious.
  • Psychodynamic Therapy — Therapy based on Freudian assumptions (the unconscious is powerful and childhood shapes adult functioning).
  • Interpersonal Psychotherapy — A modern form of psychotherapy in which the therapist helps patients identify and repair problems in adult relationships.
  • Behavioral Therapy — Therapy that uses principles of classical and operant conditioning to reduce symptoms.
  • Cognitive Behavioral Therapy (CBT) — Therapists help patients: (a) identify maladaptive beliefs, (b) replace them with adaptive beliefs, and (c) use conditioning principles to support healthier responses.