THE BIOLOGY OF MIND Cognition

DO NOW: Is the “brain” important in Psychology? How might brain functions shape our personality? Terms to Know: Neurons Neurotransmitters Central Nervous System Peripheral Nervous System Parts & Functions of the Brain Limbic System Phineas Gage

BIOLOGY, BEHAVIOR, & MIND Aristotle = Heart To think, feel, and act without a body is like… Where is the MIND? Plato = Head Biological Perspective:: The interplay of biology, behavior and the mind

NEURONS Dendrite fibers [ Listen ] Receive info & give it to cell body = nerve cells Axon fibers [ Speak ] Send info to other neurons Action potential Myelin Sheath Protective covering over axons Fatty tissue that insulates and speeds impulse Grows up to about age25 – impacts judgment, self-control, and neural efficiency multiple sclerosis – loss of muscle control

NEURAL COMMUNICATION Synapse [ Lock & Key ] Neurotransmitters impact: Hunger, Thirst, Emotions Don’t operate in isolation Acetylcholine (ACh) Opiate receptors Endorphins – natural pain killers Release Neurotransmitter Binds to receptor site Reuptake extra neurons by sending neuron Agonist : Amplifies normal sensations of pleasure Antagonist: Blocks a neurotransmitters functioning – similar enough to fill receptor site but not enough to stimulate it

Nerves = Electrical Cables NERVOUS SYSTEM Nerves = Electrical Cables Link CNS to sensory receptors The electro-chemical communication network made up of all the nerve cells of the PNS & CNS CNS (Central Nervous System) Brain & Spinal Cord PNS (Peripheral Nervous System) Gathers info & Transmits decision from the CNS Sensory & Motor System Sensory neuron carries message to spinal cord Motor neuron: carries instructions to the muscle Interneuron: Brain’s internal network More on CNS in a bit… Somatic N.S. - voluntary Automatic N.S. – i.e. heartbeat Sympathetic N.S. – alarms Parasympathetic – conserves Keep body regulated

CENTRAL NERVOUS SYSTEM (CNS) 1. BRAIN Allows us to learn Strengthens connections between neurons 2. SPINAL CORD 2 way highway between PNS & Brain Motor info Sensory Info How can this be demonstrated? 3. ENDOCRINE system Hormones Very slow moving; lasts longer at times ANS orders adrenal glands to release epinephrine & norepinephrine = increase in heart rate, bp, blood sugar Pituitary gland Controlled by hypothalamus Stimulates physical development Oxytocin (bonding), Cortisol (stress)

THE BRAIN Cerebellum Nonverbal learning & memory Judges time, monitors emotions, discriminates texture and sound Reticular Formation Sorts through stimuli Relays info to other areas of the brain Brainstem Medulla Heartbeat & Breathing Cross-over point Body x Brain Thalamus Sensory switchboard Receives all senses (but smell) Directs info to medulla & cerebellum Cerebral Cortex thin layer of interconnected neural cells Motor Cortex – Controls voluntary movement Sensory Cortex – Processes body touch and movement sensations Association areas – neurons involved in higher functioning ( speaking, remembering, thinking, learning, etc.) Parietal Lobe – Touch & body position Frontal Lobe – Speaking, muscle movement, making plans & judgments Occipital Lobe – Receiving info from visual field (eyes) Temporal Lobe – Auditory info (ears)

LIMBIC SYSTEM Amygdala “Fight or Flight” Hypothalus Hunger, Thirst, Temp Sends hormones Hippocampus Memory

CASE STUDY: PHINEAS GAGE

Divided Brain BRAIN’S PLASTICITY Ability to modify itself after damage once neuron is destroyed that’s it! BUT neural tissue can reorganize itself What does that mean? Corpus Collosum – band connecting 2 hemispheres Split Brain Left: Literal Rights: Infers, Speech, Sense of self Divided Brain