MCAT Prep Quicksheet (2023 A+)

MCAT Prep Quicksheet (2023 A+) Organization of the nervous system - ANS-There are three types of neurons in the nervous system: Motor (efferent), interneurons, and sensory (afferent) Parasympathetic Branch - ANS-The parasympathetic branch of the autonomic system is focused on "rest-and-digest" responses Sympathetic Branch - ANS-The sympathetic branch is focused on "fight-or-flight" Functions of the Parasympathetic Branch - ANS-Constricts Pupils Stimulates flow of saliva Constricts bronchi Slows heartbeat Stimulates peristalsis and secretion Stimulates bile release Contracts bladder Functions of the Sympathetic Branch - ANS-Dilates Pupils Inhibits salivation Relaxes bronchi Accelerates heartbeat Piloerection or sweating Inhibits peristalsis and secretion Stimulates glucose production and release Secretion of adrenaline and noradrenaline Inhibits bladder contraction Stimulates orgasm Organization of the brain: 3 parts - ANS-Hindbrain, Midbrain, Forebrain Hindbrain - ANS-Consists of the cerebellum, medulla, oblongata, and reticular formation Midbrain - ANS-Consists of the inferior and superior colliculi Forebrain - ANS-Consists the thalamus, hypothalamus, basal ganglia, limbic system, and cerebral cortex Parts of the Forebrain: Thalamus - ANS-relay station for sensory information Parts of the Forebrain: Hypothalamus - ANS-Maintains homeostasis and integrates with the endocrine system through the hypophyseal portal system that connects it to the anterior pituitary Parts of the Forebrain: Basal Ganglia - ANS-Smoothens movements and helps maintain postural stability Parts of the Forebrain: Limbic System - ANS-Controls emotion and memory which includes: *Septal Nuclei: pleasure seeking *Amygdala: Fear and aggression *Hippocampus: Memory *Fornix: Communication within the limbic system Parts of the Forebrain: Cerebral Cortex - ANS-Divided into four lobes: Frontal, Parietal, Occipital, Temporal Frontal Lobe - ANS-Executive function, impulse control, long-term planning (prefrontal cortex), motor function (primary motor cortex), and speech production(Broca's area) Parietal Lobe - ANS-Sensation of touch, pressure, temperature, and pain (somatosensory cortex); spatial processing, orientation, and manipulation Occipital Lobe - ANS-Visual Processing Temporal Lobe - ANS-Sound processing (auditory cortex), speech perception (Wernicke's area), memory, and emotion (Limbic System) Shortened version of the Lobes - ANS-*Frontal Lobe (Executive Function) Primary Motor Cortex *Parietal Lobe (Touch, temperature, and pain) Primary Somatosensory Cortex *Occipital Lobe (vision) *Temporal Lobe (hearing) Methods of mapping the brain - ANS-EEG rCBF CT PET MRI fMRI Influences on Behavior - ANS-aka Neurotransmitters and the resulting behavior Acetylcholine - ANS-Voluntary muscle control, parasympathetic nervous system, attention, alertness Epinephrine and Norepinephrine - ANS-Fight-or-flight responses, wakefulness, alertness Dopamine - ANS-Smooth movements, postural stability Serotonin - ANS-Mood, sleep, eating, dreaming GABA, Glycine - ANS-Brain "stabilization" Glutamate - ANS-Brain "excitation" Endorphins - ANS-Natural painkillers Nature vs. Nurture - ANS-A debate regarding the contributions of genetics (nature) and environment (nurture) to an individual's traits. Family, twin, and adoption studies are used to study nature vs. nurture. Sensation vs Perception - ANSSensation - ANS-Sensation is the conversion of physical stimuli into neurological signals Perception - ANS-Perception is the processing of sensory information to make sense of its significance Sensory receptors - ANS-Respond to stimuli and trigger electrical signals Sensory Neurons - ANS-Transmit information from sensory receptors to the CNS Sensory stimuli - ANS-Sensory stimuli are transmitted to projection areas in the brain, which further analyze the sensory input Threshold - ANS-The minimum stimulus that causes a change in signal transduction Just-noticeable difference - ANS-Minimum amount of change required in order for a difference to be perceived Weber's Law - ANS-States that the just-noticeable difference for a stimulus is proportional to the magnitude of the stimulus, and this proportional is constant over most of the range of possible stimuli. Signal detection theory - ANS-Studies the effects of nonsensory factors, such as experiences, motives, and expectations, on perception of stimuli Response Bias - ANS-Examined using signal detection experiments with four possible outcomes: hits, misses, false alarms, and correct negatives Vision - ANS-The eye is an organ specialized to detect light in the form of photons Vision pathway - ANS-Retina -- Optic Nerve -- Optic Chiasm -- Optic Tracts -- Lateral Geniculate Nucleus (LGN) of thalamus -- Visual Radiations -- Visual Cortex Hearing and Vestibular Sense - ANS-The ear transduces sound waves into electrical signals that can be interpreted by the brain Important Parts of the ear - ANS Continues...