Biological Perspective

Biological Perspective: CHAPTER 2 Neurons: generates impulses Dendrites: connection of neuron network Cell Body (soma): impulse starts here Axon: impulse travels down Myelin Sheath: protects axon Axon Terminals: impulse sent here to be distributed Neural Impulse: 1. Neuron interior charged at –70 mV 2. Incoming impulse opens gate (sodium-potassium pump) 3. Movement of ions makes internal charge +50 mV (cascade effect) 4. Sequential opening down the axon Synaptic Gap & Axon Terminal ● Neurons aren’t connected but the synaptic gap allows this transfer of energy ● Neurotransmitters are emitted from the synapse to receptors on the dendrites ● Agonist (ex. Heroin): mimics/enhances ● Substance that triggers receptor site but isn’t the neurotransmitter Antagonist (ex. Curare): blocks/reduces functioning ● Fits into receptor but doesn’t turn on neurons in excitatory or inhibitory Serotonin: associated with sleep, impulsivity, aggression, ● Too little: depression (serotonin drugs can't directly impact depression) ● Too much: mild euphoria, MDMA, neurotoxic, kills serotonin-producing cells Dopamine: associated with learning, attention, movement ● learning because you get rewarded ● Too little: Parkinson's ● Too much: Schizophrenia Increasing Neurotransmitters Levels ● Create artificial ● Inhibit reuptake (after postsynaptic neurons, they get sucked back up to be reused to be efficient) Decreasing Neurotransmitters Levels ● Reduce Production ● Block Reception (Agonist block receptor sites) ○ Can create an agonist to block a receptor site on purpose ○ Medicine can block these but when stop taking them, it unblocks symptoms The Brain Stem Medulla: Autonomic Functions (respirations, heartbeat Pons: communications with cerebellum, motor movements are done in certain ways, shuts off part of brain during REM sleep for voluntary movement Reticular Formation: arousal, attention (instantly aware of loud noises, looking in direction of sound/startled) (physiological arousal when sleeping and waking up during season changes and sun changes, light triggers to wake) Cerebellum: coordinating involuntary fine motor movement Limbic System Thalamus: sensory switchboard Hypothalamus: TONS of stuff, significant functions - whatever the medulla doesn’t regular, manages hormones released/working with pituary gland, temperature Hippocampus: encoding memory, patterns can become more learned, engaging Amygdala: negative emotional response; dangerous fear = do something abt it for survival Central Cortex Hemispherical Lateralization: function is not only in a hemisphere, but predominantly so ● More in 1 side, but the other side still plays a role: working together for full process Left Hemisphere: logical, language, componential processes, time perception ● Occurs in bits and assemble (math) Right Hemisphere: holistic focus: images, patterns, creativity, emotional recognition Corpus Callosum: made up of myelin & connects neurons on both hemispheres fast The Lobes Frontal Lobe: executive function (decision making, planning) ● Motor Strip: motor control (back/posterior of frontal lobe) ○ Right side controls left body, vice versa ○ Complexity more important than size (ex. Mouth has more than bottom) Parietal Lobe: touch, temperature, pain to interact approatiately to it for survival ● Somatosensory Strip: carries information from sensory info and telling how to interact with it (anterior to parietal lobe next to motor strip) ○ Has divisions based on (ex. Elbow vs nose, or phantom limb cuz part of brain says it hurts even if doesn’t have sensations in the limb) Occipital Lobe: Primary Visual Cortex Temporal Lobe: Primary Auditory Cortex, hearing and processing info, sort out sounds and its importance