PSY 209 Exam 4 Study Guide

Module 9: Emotions and Their Display

Types of Emotions

  • We experience a range of emotions: joy, sadness, affection, disgust, anger, fear, expectation, surprise.

  • Each emotion typically has a distinctive facial expression, recognized across diverse cultures.

  • This universal recognition suggests emotions are evolved traits aiding social interactions.

Nervous System and Emotions

  • Autonomic Nervous System (ANS):

    • Comprises sympathetic (fight or flight) and parasympathetic (rest and recuperation) systems.

    • Controls automatic bodily functions necessary for survival (e.g., heart rate, blood pressure, digestion).

Facial Expressions

  • Mediated by:

    • Superficial Facial Muscles:

      • Change facial shape (e.g., frontalis muscle wrinkles the forehead).

    • Deep Facial Muscles:

      • Attach to bones (e.g., temporalis muscle for chewing).

    • Nerves:

      • Facial nerve (VII) controls superficial muscles.

      • Trigeminal nerve (V) innervates deep muscles.

    • Impairment in these muscles affects social interactions (e.g., Parkinson’s disease, certain viral infections).

Evolution and Function of Emotions

  • Emotions evolved to provide survival and social benefits:

    • Fear triggers physiological responses (heightened awareness, increased heart rate) preparing fight or flight.

    • Anxiety promotes caution in uncertain scenarios, avoiding potential risks.

  • Emotional expressions vary across species influenced by communication needs and social complexity.

Brain Circuits in Emotional Processing

  • Interconnected brain circuits primarily located in the limbic system:

    • Key regions include:

      • Amygdala

      • Prefrontal cortex

      • Hippocampus

      • Hypothalamus

      • Insular cortex

      • Cingulate cortex

      • Basal ganglia

      • Thalamus

James Papez’s Theory

  • Proposed a subcortical circuit of emotions (the Papez Circuit):

    • Includes mammillary bodies, anterior thalamus, cingulate cortex, hippocampus, fornix.

  • Related to emotion-linked brain damage.

Klüver–Bucy Syndrome

  • Characterized by emotional changes; reduced fear and anxiety.

  • Noted following bilateral amygdala damage.

Roles of the Amygdala in Fear Conditioning

  • The amygdala has two subdivisions relevant to fear:

    • Basolateral Amygdala (BLA):

      • Encodes emotional responses, notably fear.

      • Outputs key connections to prefrontal cortex and hippocampus.

    • Central Nucleus Amygdala (CeA):

      • Evokes appropriate responses during fearful situations.

      • Outputs include hypothalamus and brainstem.

Neural Circuitry in Fear Conditioning

  • Fear conditioning links neutral stimuli with aversive ones (e.g., sound with shock):

    • Sensory Input Pathways:

      • Auditory and somatosensory thalamus pathways to the amygdala.

    • Integration:

      • Processing convergence of tone and shock signals in BLA.

    • Output Pathways:

      • From BLA to CeA to initiate fear responses via hypothalamus and brainstem.

Fear Extinction and Brain Interaction

  • Fear extinction reduces conditioned fear responses through interaction:

    • Involves prefrontal cortex, amygdala, hippocampus in regulating the extinction memory.

Taste Hedonics

  • Sweet-tasting foods eliciting acceptance responses and increased liking ratings:

    • Measured through universal cross-species reactions, particularly involving opioid pathways.

Neuropsychiatric Disorders: Module 10

Overview of Disorders

  • Neuropsychiatric illnesses address mental disorders linked to central nervous system diseases.

    • Epidemiology studies the spread and control of these health conditions, costing an estimated $273 billion/year.

Endophenotypes in Mental Health

  • Anhedonia:

    • Reduces pleasure in daily activities.

  • Avolition:

    • Difficulty initiating and maintaining activities.

Schizophrenia

  • Characterized by:

    • Positive symptoms (gain of function) such as hallucinations and delusions.

    • Negative symptoms (loss of function) that disrupt normal emotional expression.

    • Cognitive symptoms affecting attention and memory.

Neurochemical Changes in Schizophrenia

  • Involves dysregulation in neurotransmitters:

    • Dopamine, glutamate, GABA, and serotonin imbalances.

Genetic and Environmental Influences

  • Heritability observed through family and twin studies.

    • DISC1 gene linked to schizophrenia risk.

Hypofrontality Hypothesis

  • Suggests reduced prefrontal cortex activity correlating with symptoms of schizophrenia, impacting decision-making and social behavior.

Treatment Approaches

  • Neuroleptics (Antipsychotic Drugs):

    • Divided into typical (dopamine blockers, primarily for positive symptoms) and atypical (treat both positive and negative symptoms).

  • Depression

    • Major depressive disorder involves prolonged low mood.

  • Understanding brain changes such as increased blood flow in critical regions.

  • Treatment options include electroconvulsive therapy, transcranial magnetic stimulation, and selective serotonin reuptake inhibitors.

Memory and Learning: Module 11

Basics of Learning and Memory

  • Learning is the acquisition of information; memory enables recall or recognition of experiences.

  • The process involves strengthening synapses upon repeated activation (Hebbian learning).

Long-Term Potentiation (LTP)

  • Key mechanism for memory formation is LTP, which involves NMDA and AMPA receptors.

  • Observed in various brain regions including hippocampus and amygdala.

Brain Plasticity

  • Reflects the brain's ability to adapt to experiences, showing structural changes like synaptic strengthening and receptor density changes important for memory.

Types of Memory

  • Declarative Memory (Explicit):

    • Conscious recall of facts and experiences.

  • Skill Memories (Implicit):

    • Performing tasks without conscious awareness.

Memory Processes

  • Memory consolidation strengthens memory through protein synthesis, vulnerable during a labile state.

  • Distinction made between anterograde (new memories) and retrograde (past memories) amnesia based on condition onset.

Influential Case Studies

  • Case of Henry Molaison (H.M.) highlights essential memory mechanisms and centers of learning.