Origins and Functions of Brain and Behavior

Forebrain

Responsible for conscious behavior in mammals/birds.

Brainstem

Controls unconscious behavior like heart rate.

Cerebellum

Involved in learning and coordinating movements.

Conscious Behavior

Awareness of actions like writing.

Unconscious Behavior

Unawareness of actions like digestion.

Learnt Behavior

Influenced by culture, values, and education.

Inherited Behavior

Instinctive actions like sucking in infants.

Mentalism

Mind (psyche) drives behavior, per Aristotle.

Dualism

Mind and body both influence behavior, per Descartes.

Materialism

Behavior explained by nervous system functions, per Darwin.

Intelligence Measurement

Gardner's theory includes multiple intelligences.

IQ Test Increase

Scores rose by 25 points across generations.

Brain Size

Increases across species groupings.

Relative Brain Size

Humans have largest brain relative to body.

Brain Size Factors

Enlarged by climate change, nutrition, and cooking.

Cerebral Cortex

Main brain region with four lobules.

Occipital Lobe

Processes visual information.

Parietal Lobe

Involved in sensory perception and integration.

Temporal Lobe

Handles auditory information and memory.

Frontal Cortex

Responsible for decision-making and impulse control.

Limbic System

Emotional regulation and memory processing.

Amygdala

Key role in processing emotions, especially fear.

Broca's Area

Critical for speech production.

Frontal lobe

Responsible for executive function and short-term memory.

Prefrontal cortex

Plans movements, located near the frontal lobe.

Corpus callosum

Connects brain hemispheres with 200 million nerve fibers.

Brain stem

Controls life-sustaining behaviors; includes hindbrain and midbrain.

Basal ganglia

Coordinates voluntary movements; linked to motor disorders.

Somatosensory cortex

Produces sensations mapped to body parts in parietal lobe.

Premotor cortex

Organizes movement sequences, located behind the prefrontal cortex.

Motor cortex

Generates specific movements, located behind premotor cortex.

Broca's area

Speech production area in the left frontal lobe.

Dorsal

Refers to the top or within structure.

Ventral

Refers to the bottom structure.

Anterior

Indicates the front of a structure.

Posterior

Indicates the back of a structure.

Medial

Indicates proximity to the midline.

Lateral

Indicates proximity to the sides.

Afferent

Nerve signals that enter the central nervous system.

Efferent

Nerve signals that exit the central nervous system.

Central nervous system (CNS)

Comprises the brain and spinal cord.

Peripheral Nervous System (PNS)

Transmits messages between CNS and body.

Somatic nervous system (SNS)

Carries sensory info to CNS and motor instructions.

Automatic nervous system (ANS)

Regulates involuntary bodily functions; includes sympathetic and parasympathetic.

Sympathetic nervous system

Triggers fight or flight response.

Parasympathetic nervous system

Promotes rest-and-digest activities.

Enteric nervous system

Controls gut function through embedded neurons.

Neuron

Cell that transmits information in the brain.

Sensory neuron

Conveys information from body to brain.

Motor neuron

Commands muscles to move.

Interneuron

Links sensory and motor neurons in CNS.

Glial cells

Support neurons and maintain homeostasis.

Ependymal cells

Secretes cerebrospinal fluid, small ovoid shape.

Astrocyte

Provides nutrition, supports repair, forms blood-brain barrier.

Microglial cell

Removes dead tissue, derived from blood.

Oligodendroglia cell

Forms myelin around CNS axons.

Schwann cell

Wraps around peripheral nerves to form myelin.

Dendrites

Collect information from other neurons.

Cell body (soma)

Processes information received by neuron.

Nucleus

Contains chromosomes and processes information.

Axon

Transmits information to other cells.

Axon collateral

Branch of an axon transmitting information.

Teleodendria

Smaller branches from axon collateral.

Terminal button

End of neuron where synapse occurs.

Blood-brain barrier

Protective barrier between blood vessels and brain.

Resting potential

Electrical charge across membrane without stimulation.

Action potential

Brief reversal of axon membrane polarity.

Graded potentials

Small voltage fluctuations across cell membrane.

Sodium-potassium pump

Pumps 3 sodium out for every 2 potassium in.

Acetylcholine

Neurotransmitter released at motor neuron axon terminal.

Sensitisation

Increased response to repeated drug doses.

Withdrawal

High motivation to seek drug after cessation.

Tolerance

Reduced response requiring higher doses for effect.

Metabolic tolerance

Increased liver enzymes break down substances.

Cellular tolerance

Brain cell adjustments minimize drug effects.

Learned tolerance

Coping mechanisms developed for intoxication.

Mesolimbic pathways

Dopamine pathways linked to addiction behaviors.

Incentive-Sensitization Theory

Cues trigger drug craving independent of pleasure.

Wanting

Craving for a drug without immediate pleasure.

Liking

Pleasure derived from drug consumption.

Hormones

Glandular secretions regulating body functions.

Hypothalamus

Brain region controlling pituitary gland functions.

Pituitary gland

Master gland regulating hormone release.

Electroencephalograph (EEG)

Measures electrical activity from neuron potentials.

Magnetoencephalography (MEG)

Detects magnetic fields from neuronal activity.

Transcranial magnetic stimulation (TMS)

Stimulates brain regions using magnetic fields.

Single-cell recording

Measures action potentials from individual neurons.

Event-related potentials (ERPs)

Waveforms linked to specific sensory events.

Feedback loops

Hormonal interactions regulating physiological activities.

Addictive drugs

Substances causing compulsive behavior and cravings.

Behavioural addictions

Compulsive behaviors mimicking substance addiction.

Dopamine (DA) activity

Neurotransmitter linked to reward and motivation.

Primary motor cortex

Specifies execution of focal skill movements.

Spinal cord

Transmits information between PNS and brain.

Monosynaptic reflex

One synapse between sensory input and movement.

Multisynaptic reflex

Connections among sensory, inter, and motor neurons.

Lateral corticospinal tract

Crosses to control limbs on opposite body side.

Anterior corticospinal tract

Does not cross; controls midline body movements.

Locked-in syndrome

Awareness with paralysis, except for eye movement.

Parkinson's disease

Hypokinetic symptoms include tremor and impaired balance.