Unit+1+Biological+Bases+of+Behavior

Learning Targets Checklist

• Heredity and Environment: Explain their relationship in shaping behavior and mental processes.

• Nervous System Subsystems: Differentiate among types and their functions.

• Neurons in CNS: Explain how their structure and function affect behavior.

• Neural Transmission: Relate the basic process to behavior and mental processes.

• Psychoactive Drugs: Explain their effects on behavior and mental processes.

• Brain Structures and Functions: Explain their application to behavior and mental processes.

• Sleep/Wake Cycle: Explain its effects on behavior throughout the day and night.

• Sensation Process: Explain its relation to behavior and mental processes.

• Visual Sensory System: Explain structure and function relating to behavior.

• Auditory Sensory System: Explain structure and function relating to behavior.

• Chemical Sensory Systems: Explain structure and function relating to behavior.

• Touch Sensory System: Explain structure and function relating to behavior.

• Pain Sensory System: Explain structure and function relating to behavior.

• Vestibular and Kinesthetic Senses: Explain their relation to behavior.

Introduction to Psychology

• Definition: Psychology is the science of behavior and mental processes.

• Evolution of Approaches: Various new approaches emerged to study mind and behavior as psychology grew in popularity.

Nature vs. Nurture Debate

• Overview: A major discussion on whether psychological traits and behaviors are primarily influenced by genetics or environment.

• Example: Interest in discussions about serial killers—whether they are born or made.

Survival of the Fittest

• Behavior Geneticists: Explore genetic and environmental influences on human differences.

• Evolutionary Psychologists: Examine common traits among humans through evolutionary principles.

  • Natural Selection: Inherited traits that enhance survival and reproduction are more likely to be passed on.

  • Adaptation: Process of species fitting into their environments.

  • Mutation: Random genetic changes affecting traits.

• Biological Basis: Highlight that all psychological phenomena are biologically rooted.

Behavior Genetics

• Context: Investigate the influence of genetics and environment on behavior.

  • Heredity: Genetic transfer from parents to offspring.

  • Environment: All non-genetic influences.

  • Eugenics: The science aimed at improving human populations through controlled breeding.

Genes and Chromosomes

• Chromosomes: Thread-like structures of DNA containing genes.

• DNA: Molecule with genetic information for chromosomes.

• Genes: Hereditary units capable of synthesizing proteins.

• Genome: Complete genetic instruction set for organisms.

• Molecular Genetics: Subfield studying gene function.

• Heritability: Variation attribution among individuals due to genetics.

Twin and Adoption Studies

• Importance: Researchers study twins to examine nature versus nurture influences on behavior.

  • Identical Twins: Originating from one fertilized egg; share identical genes.

  • Fraternal Twins: Develop from separate eggs; genetically similar as siblings.

• Research Field: Epigenetics studies environmental effects on gene expression.

The Nervous System Overview

• Definition: The body’s communication network; quick electrochemical messaging system from nerve cells.

• Divisions:

  • Central Nervous System (CNS): Includes brain and spinal cord.

  • Peripheral Nervous System (PNS): Sensory and motor neurons connecting to CNS.

    • Autonomic Nervous System: Controls involuntary functions.

      • Sympathetic: Arouses body for fight or flight.

      • Parasympathetic: Calms body post-stress.

    • Somatic Nervous System: Controls voluntary movements.

      • Afferent Nerves: Relay sensory information to CNS.

      • Efferent Nerves: Signal voluntary muscle movement.

Reflexes and Interneurons

• Reflexes: Automatic responses to stimuli; sensory information travels via spinal cord; some react only within the spinal cord, bypassing brain processing.

• Interneurons: Neurons that facilitate communication within the brain and spinal cord.

Chemical and Electrical Communication

• Neurons: Billions of nerve cells in the nervous system; basic components include soma, dendrites, axon, and axon terminals.

• Neural Firing: Neurons communicate through electrical signals (action potentials) and chemical neurotransmitters.

• Resting Potential: Neuron's charge at rest, while firing an impulse is called action potential—switching ions alters charge:

  • All-or-Nothing Law: Neurons either fire fully or not at all once the threshold is reached.

  • Refractory Period: Time when a neuron cannot fire again.

Neurotransmitters Overview

• Function: Chemical messengers relaying signals across synapses.

• Common Neurotransmitters:

  • Acetylcholine: Muscle action, learning, memory; linked to Alzheimer’s.

  • Dopamine: Motor movement, learning, attention; linked to Parkinson’s and schizophrenia.

  • Serotonin: Mood, hunger; associated with depression.

  • GABA: Inhibitory neurotransmitter; lack leads to seizures; oversupply can reduce anxiety.

  • Glutamate: Involved in memory; associated with seizures in excess.

• Drug Interactions: Psychoactive drugs that affect neurotransmitters also influence mood and behavior.

Sleep and Consciousness

• Sleep Functions: Essential for restoration and cognitive processes.

• Stages of Sleep:

  • NREM (non-rapid eye movement) stages and REM sleep, characterized by different brain waves and functions.

• Sleep Disorders: Insomnia, narcolepsy, sleep apnea, night terrors, etc.

Sensation and Perception

• Definitions: Sensation vs. perception; distinction between receiving and interpreting sensory information.

• Processes:

  • Bottom-up vs. top-down processing.

  • Transduction: Conversion of sensory stimuli into neural impulses.

Vision and Hearing

• Visual System: Mechanisms of sight, including structures like the cornea, lens, and retina.

• Auditory System: The ear structure, sound wave processing, and the pathway to the auditory nerve.

Taste and Touch

• Taste: Chemical receptors on papillae identify various taste sensations.

• Touch Sensations: Pain, pressure, warmth; processed in the parietal lobe.

Conclusion

• Understanding these elements provides insights into human behavior, mental processes, and their biological foundations.