Chapter 3: Biology and Behavior

Chapter 3: Biology and Behavior

Neuropsychology

•The study of the relationship between the brain/body and behavior

•Human Nervous System

–Peripheral

–Central

Peripheral Nervous System

•Nerves lying outside the brain and spinal cord

•Autonomic Nervous System

–heart, lungs, stomach, etc.

• Sympathetic Nervous System

• Parasympathetic Nervous System

• Somatic Nervous System

Central Nervous System

•Control center

•Brain and spinal cord

•Sends/receives information to/from the peripheral nervous system

Types of Neurons

•Sensory Neurons (afferent neurons)

–from ears, eyes, tongue, and skin

•Motor Neurons (efferent neurons)

–from CNS to muscles

–Reflex: within spinal cord

•Interneurons

–sensory neurons to motor neurons

Nature of the Message

•Electrochemical impulse

Types of Neurons

•Action Potential

–240 mph

•All or Nothing LawNeuron fires or notRefractory Period

Neural Communication

•Neurons separated by a synapse

•Communication = neurotransmitters

Lock & Key Hypothesis

Agonist: Mimics

Agtagonist: Blocks

Two Classes of Neurotransmitters

•Excitatory Neurotransmitters

–Increases action potential

•Inhibitory Neurotransmitters

–Decreases action potential

Prominent Neurotransmitters

•Acetycholine (Ach)Voluntary musclesConvulsions = Abundance of AchLearning and MemoryDecrease = Alzheimer’s Disease

•Norephinephrine (or Noradrenaline)General arousal and mood Highly pleasurable reactionsamphetaminesSmoking

•DopamineInfluences learning and memory and emotional reactionsFactor in schizophrenia and Tourette’s syndrome

Blocking it used to treat psychosis

–L-Dopa (Laevodihydroxyphenylaline)Loss = slowness & inability to moveParkinson’s disease

•SerotoninAssoc. with sleep & food metabolism foods high in carbohydrates enhance production (e.g., Turkey)Related to drepression

•GABA (Gamma Amino Butyric Acid)Inhibitory NeurotransmitterBalances other neurotransmittersDeficit = Epilepsy

Endocrine System

•Ductless glands: right to bloodstream

•Secrete hormonesAdrenaline EpinephrineNoradrenaline Norepinephrine

•Global Communication

•Much slower than nervous system

•Effects are longer lasting

–Fight or flight

Endocrine Glands

•Pituitary Gland (pea)located in the brainmaster glandthermostatclosely connected to nervous system

•Thyroid Glandlocated next to trachea & larynxcontrols metabolismeffects energy level and mood

•Adrenal Glandlocated above the kidneyssecretes adrenaline

•Pancreaslocated near the stomachcontrols blood-sugar level

•GonadsProduces testosterone in malesProduces estrogen in femalesControls sex drive and secondary sex characteristics

Subdivisions of the Brain

•Hindbrain: Vital functionsMedullaCerebellum

•Midbrain: Processes informationReticular formationmaintains consciousnessfinger-shaped network of neurons

•Forebrain: Perceiving, remembering, and thinking

•Thalamus

•Hypothalamus

•Cortex

Split-Brain Research

•Structural Symmetry

•Cross Wiring

–Right hemisphere controls left side

–Left hemisphere controls right side

•Visual Fields

•Each eye receives sensory information from the right and left visual fields

•Transmitted quickly to the other hemisphere

•Corpus Callosum

•Thick band of neurons connecting the two hemispheres

•Left HemisphereUse of Words NumbersReasoningDominant in language and writing skills

•Right HemisphereObject assemblyFacial recognitionSpatial tasksDominant in language and writing skills