Biological Psychology

Evolutionary Psychology

  • Studies how behaviors and mental processes are shaped by natural selection, promoting survival and reproduction.

Natural Selection

  • The process where organisms better adapted to their environment tend to survive and produce more offspring.

Nature

  • Refers to all genetic and inherited factors that influence an individual's development, including physical characteristics and predispositions.

Nurture

  • Encompasses all environmental influences that affect an individual's development, such as family, education, culture, and experiences.

Twin Studies

  • Research method comparing identical (monozygotic) and fraternal (dizygotic) twins to understand the relative contributions of genetics and environment to traits and disorders.

Adoption Studies

  • Research method comparing adopted children to their biological and adoptive parents to assess the influence of heredity versus environment.

Family Studies

  • Studies examining patterns of traits or disorders within families to determine genetic vulnerabilities and environmental influences.

Heredity

  • The transmission of genetic characteristics from parents to their offspring.

Genetic Predisposition

  • An increased likelihood of developing a particular disease or trait based on an individual's genetic makeup.

Eugenics

  • A discredited social movement aimed at improving the human race through selective breeding, often involving coercive and unethical practices.

    • Historical context: Emerged in the late 19th century aiming to improve human genetics but became linked to racism, forced sterilization, and genocide.

    • Key Figures: Found by Francis Galton and promoted by Charles Davenport

    • Ethical Considerations: Raises moral concerns about reproductive rights, consent, and defining “desirable” traits; historically led to major human rights abuses.

    • Significant Events:

      • Early 1900s: Eugenic policies adopted in the U.S. and Germany.

      • Post-WWII: Decline after Nazi crimes exposed its dangers

    • Modern Relevance: New genetic tools like CRISPR reignite ethical debates about genetic enhancement and the risk of modern eugenics.

    • Criticism and Controversy: Condemned for racism, pseudoscience, and unethical practices; modern science rejects its principles.

Cerebral Cortex

  • The outermost layer of the cerebrum, responsible for higher-level cognitive functions like perception, language, memory, and consciousness.

Lobes of the Brain

  • The four major divisions of the cerebral cortex: Frontal, Parietal, Temporal, and Occipital Lobes, each with specialized functions.

Association Areas

  • Regions of the cerebral cortex that are not involved in primary motor or sensory functions but integrate information from various parts of the brain.

Frontal Lobe

  • Location: front of the brain, behind the forehead.

  • Functions: planning, decision-making, voluntary movement, personality, and executive functions.

Motor Cortex

  • Location: posterior part of the frontal lobe.

  • Function: controls voluntary movements of the body.

Prefrontal Cortex

  • Location: most anterior part of the frontal lobe.

  • Functions: complex cognitive behaviors, personality expression, decision-making, and moderating social behavior.

Executive functioning

  • A set of cognitive processes located in the prefrontal cortex that allow for goal-directed behavior, including planning, working memory, inhibitory control, and cognitive flexibility.

Parietal Lobes

  • Location: top and rear of the brain.

  • Functions: processing sensory information (touch, temperature, pain), spatial awareness, and navigation.

Somatosensory Cortex

  • Location: anterior part of the parietal lobe.

  • Function: receives and processes sensory input from the body, such as touch, pressure, temperature, and pain.

Occipital Lobes

  • Location: back of the brain.

  • Function: primarily responsible for processing visual information.

Temporal Lobes

  • Location: sides of the brain, below the parietal and frontal lobes.

  • Functions: auditory processing, memory, and language comprehension.

Corpus Callosum

  • A thick band of nerve fibers connecting the two hemispheres of the brain, allowing them to communicate.

Brainstem

  • Location: base of the brain, connecting the cerebrum and cerebellum to the spinal cord.

  • Functions: regulates basic life functions like breathing, heart rate, sleep, and consciousness.

Medulla

  • Location: lowermost part of the brainstem.

  • Functions: controls vital involuntary functions such as heart rate, breathing, and blood pressure.

Reticular Activating System

  • A network of neurons extending through the brainstem.

  • Functions: regulates arousal, consciousness, sleep-wake transitions, and attention.

Cerebellum

  • Location: beneath the occipital and temporal lobes, at the back of the brain.

  • Functions: coordinates voluntary movements, balance, posture, and motor learning.

Limbic System

  • A group of structures located below the cerebral cortex.

  • Functions: involved in emotion, motivation, memory, and learning.

  • Includes the amygdala, hippocampus, thalamus, and hypothalamus.

Reward Center

  • Neural pathways and structures (primarily involving the ventral tegmental area and nucleus accumbens) that produce feelings of pleasure and motivation in response to certain stimuli.

Thalamus

  • A relay station for sensory information (except smell) to the cerebral cortex and motor signals from the cerebellum and basal ganglia to the cortex.

Hypothalamus

  • Location: below the thalamus.

  • Functions: regulates basic biological needs like hunger, thirst, body temperature, and also involved in emotional responses.

Pituitary Gland

  • A small gland at the base of the brain, often called the "master gland" because it controls other endocrine glands and regulates growth and various bodily functions.

Hippocampus

  • Location: temporal lobe, part of the limbic system.

  • Function: critical for the formation of new memories and spatial navigation.

Amygdala

  • Location: almond-shaped structure in the temporal lobe, part of the limbic system.

  • Function: primarily involved in processing emotions, especially fear and aggression.

The Nervous System

  • The body's communication network, composed of nerves and specialized cells that transmit information throughout the body.

Lobes of the Brain

  • Frontal Lobe: Executive Control Center

  • Parietal Lobe: Sensory Processing Hub

  • Occipital Lobe: Visual Processing Center

  • Temporal Lobe: Auditory Center

Central Nervous System

  • Components: brain and spinal cord.

  • Function: integrates and processes all incoming sensory information and outgoing motor commands.

Peripheral Nervous System

  • Components: all nerves outside the brain and spinal cord.

  • Function: connects the CNS to the rest of the body, including organs, muscles, and glands.

Autonomic System

  • A division of the PNS that regulates involuntary bodily functions like heart rate, digestion, respiration, and arousal.

Sympathetic Nervous System

  • A division of the autonomic nervous system.

  • Function: responsible for the "fight or flight" response, preparing the body for stressful situations (e.g., increasing heart rate, dilating pupils).

Parasympathetic Nervous System

  • A division of the autonomic nervous system.

  • Function: responsible for "rest and digest" functions, conserving energy and calming the body (e.g., slowing heart rate, stimulating digestion).

Somatic Nervous System

  • A division of the PNS that controls voluntary movements of skeletal muscles and transmits sensory information from the body to the CNS.

Neurons (Motor Neurons, Sensory Neurons, Interneurons)

  • Neurons: fundamental units of the nervous system that transmit electrical and chemical signals.

    • Motor Neurons: transmit signals from the CNS to muscles and glands, initiating movement.

    • Sensory Neurons: transmit sensory information from the body's receptors (e.g., skin, eyes) to the CNS.

    • Interneurons: found within the CNS, they communicate between sensory and motor neurons.

Glial Cells (Reflex Arc)

  • Glial Cells: support cells in the nervous system that provide nourishment, insulation, and waste removal for neurons, maintaining neural environment.

  • Reflex Arc: A neural pathway that mediates a reflex action (involuntary response) without direct involvement of the brain.

Neural Transmission

  • The process by which neurons communicate, involving the transmission of electrical signals (action potentials) and chemical signals (neurotransmitters) across synapses.

Threshold

  • The minimum level of stimulation required to trigger a neural impulse (action potential) in a neuron.

Action Potential

  • A brief, rapid electrical impulse that travels down the axon of a neuron, caused by a change in electrical charge across the neuron's membrane.

All-or-Nothing Principle

  • States that an action potential either fires at full strength or not at all; there is no partial firing.

Depolarization

  • The initial phase of an action potential where the inside of the neuron's membrane becomes more positive due to the influx of positive ions (e.g., Na^+).

Refractory Period

  • A brief period following an action potential during which a neuron cannot fire another action potential, ensuring signal directionality and limiting firing rate.

Resting Potential

  • The electrical potential difference across the membrane of a neuron when it is not actively transmitting a signal, typically around -70 mV (millivolts), with the inside being negative relative to the outside.

Reuptake

  • The process by which neurotransmitters are reabsorbed by the presynaptic neuron after signaling, to terminate their effect and conserve neurotransmitter molecules.

Multiple Sclerosis “MS”

  • A chronic, often progressive autoimmune disease that damages the myelin sheath protecting nerve fibers in the CNS, leading to impaired communication between the brain and body.

Myasthenia Gravis

  • A chronic autoimmune neuromuscular disease characterized by fluctuating weakness of voluntary muscles, caused by a breakdown in communication between nerves and muscle cells.

Synapse for Neural Transmission (Presynaptic Terminal, Synaptic Cleft, Postsynaptic Membrane, Neurotransmitters, Receptors, Ion Channels)

  • Synapse: The junction between two neurons where signals are transmitted.

    • Presynaptic Terminal: The end of the axon of the transmitting neuron, containing neurotransmitters.

    • Synaptic Cleft: The microscopic gap between the presynaptic terminal and postsynaptic membrane.

    • Postsynaptic Membrane: The membrane of the receiving neuron, containing receptors.

    • Neurotransmitters: Chemical messengers released into the synaptic cleft to transmit signals.

    • Receptors: Proteins on the postsynaptic membrane that bind to specific neurotransmitters.

    • Ion Channels: Pores in the postsynaptic membrane that open when activated by neurotransmitters, allowing ions to flow in or out and changing the neuron's electrical potential.

Neurotransmitters (Excitatory Neurotransmitters, Inhibitory Neurotransmitters)

  • Neurotransmitters: Chemical messengers that transmit signals across a synapse from one neuron to another.

    • Excitatory Neurotransmitters: Increase the likelihood that the postsynaptic neuron will fire an action potential.

    • Inhibitory Neurotransmitters: Decrease the likelihood that the postsynaptic neuron will fire an action potential.

Glutamate

  • Major excitatory neurotransmitter in the CNS, involved in learning and memory.

    • Surplus Effects: Excessive excitation, potential seizures

    • Deficit Effects: Impaired Learning and memory, cognitive deficits

    • Possible Disorders: Epilepsy, Alzheimer’s disease, schizophrenia

GABA

  • Major inhibitory neurotransmitter in the CNS, reducing neuronal excitability.

    • Surplus Effects: Excessive inhibition, sedation, reduced anxiety

    • Deficit Effects: Anxiety, insomnia, seizures

    • Possible Disorders: Anxiety disorders, insomnia, epilepsy

Dopamine

  • Involved in reward, pleasure, motivation, motor control, and attention; imbalances are linked to Parkinson's disease and schizophrenia.

    • Surplus Effects: Increased pleasure, motivation, risk-taking behavior

    • Deficit Effects: Reduced motivation, depression, motor impairment

    • Possible Disorders: Parkinson’s disease, depression, addiction

Serotonin

  • Influences mood, sleep, appetite, and well-being; imbalances are linked to depression and anxiety.

    • Surplus Effects: Improved mood, decreased appetite, better sleep

    • Deficit Effects: Mood disorders, anxiety, appetite disturbances

    • Possible Disorders: Depression, anxiety disorders, eating disorders

Endorphins

  • Natural pain relievers produced by the body, also involved in feelings of pleasure and euphoria.

    • Surplus Effects: Pain relief, euphoria

    • Deficit Effects: Increased pain sensitivity, dysphoria

    • Possible Disorders: Chronic pain conditions, depression

Substance p

  • A neurotransmitter involved in the transmission of pain signals from the periphery to the CNS.

Acetylcholine

  • Involved in muscle contraction (at neuromuscular junctions), learning, memory, and attention; deficits are linked to Alzheimer's disease.

    • Surplus Effects: Enhanced memory and attention

    • Deficit Effects: Memory deficits, cognitive decline

    • Possible Disorders: Alzheimer’s disease, myasthenia gravis

Hormones

  • Chemical messengers produced by endocrine glands and released into the bloodstream, regulating various bodily functions and influencing behavior.

Ghrelin

  • A hormone produced in the stomach that stimulates appetite, often called the "hunger hormone."

Leptin

  • A hormone produced by fat cells that signals satiety (fullness) to the brain, regulating long-term energy balance.

Melatonin

  • A hormone produced by the pineal gland that regulates sleep-wake cycles (circadian rhythms).

Oxytocin

  • A hormone and neurotransmitter involved in social bonding, trust, empathy, and maternal behaviors, often called the "love hormone."

Adrenaline

  • Also known as Epinephrine, a hormone and neurotransmitter involved in the "fight or flight" response, increasing heart rate and energy.

Norepinephrine

  • A hormone and neurotransmitter involved in alertness, arousal, attention, and the "fight or flight" response; also known as Noradrenaline.

Plasticity

  • The brain's ability to reorganize itself by forming new neural connections throughout life, allowing it to adapt to new experiences, learning, and injury.

Split Brain research

  • Studies conducted on patients whose corpus callosum has been severed (to treat severe epilepsy), revealing insights into hemispheric specialization and communication.

Contralateral Hemispheric Organization

  • The principle that the right hemisphere of the brain controls the left side of the body, and the left hemisphere controls the right side of the body.

Hemispheric Specialization

  • The tendency for each of the brain's two hemispheres to excel at particular functions (e.g., left for language, right for spatial reasoning).

Linguistic Processing

  • The cognitive processes involved in understanding, producing, and interpreting language.

Broca’s Area

  • Location: left frontal lobe.

  • Function: primarily involved in speech production and language expression.

Broca’s Aphasia

  • A language disorder resulting from damage to Broca's Area, characterized by difficulty producing speech (non-fluent aphasia) but relatively intact language comprehension.

Wernicke’s Area

  • Location: left temporal lobe.

  • Function: primarily involved in language comprehension and understanding.

Wernicke’s Aphasia

  • A language disorder resulting from damage to Wernicke's Area, characterized by difficulty understanding language and producing fluent but often meaningless speech (fluent aphasia).

Electroencephalogram “EEG”

  • A neuroimaging technique that measures electrical activity in the brain through electrodes placed on the scalp, used to study brain waves and states.

Functional Magnetic Resonance Imaging “fMRI”

  • A neuroimaging technique that measures brain activity by detecting changes in blood flow (and thus oxygen use) in specific brain regions, providing both structural and functional information.

Lesioning

  • An experimental technique involving the destruction or removal of specific brain tissue to study the behavioral and cognitive effects of such damage.