PSYC 450 FINAL EXAM QUESTIONS WITH VERIFIED SOLUTIONS LATEST UPDATE 2026

PSYC 450 FINAL EXAM QUESTIONS WITH VERIFIED SOLUTIONS LATEST UPDATE 2026 cutaneous senses - Answers Responsible for perceptions stimulated by the skin (e.g., touch and pain); Grasping, protecting against damage, motivating sexual activity Proprioception - Answers Position of body and limbs (Vestibular influences) kinesthesis - Answers Movement of body and limbs (Vestibular influences) skin - Answers 1. Heaviest organ 2. Largest sensory system 3. Prevents body fluids from escaping 4. Protects the body from bacteria, chemical agents, dirt, etc. 5. Provides us with information about various stimuli Epidermis - Answers outer layers of the skin (dead skin cells) Dermis - Answers middle layer of skin below epidermis Mechanoreceptors - Answers receptors that respond to mechanical stimulation, like pressure, stretching and vibration Merkel receptors - Answers found in the valleys of finger prints; smallest receptive fields; high spatial resolution; form and texture coding; can become malignant; 25% of mechanoreceptors in hand Meissner's corpuscles - Answers sensitive touch receptors in the dermis Ruffini cylinder - Answers fires continuously to stimulation; associated with perceiving stretching of skin Pacinian corpuscles - Answers respond to deep pressure and vibration (fires when pressure is first administered and when it is removed); recording from fibers; assisted with PC shows they respond poorly to slow or constant pushing and respond well to high rates of vibration medial lemniscal pathway - Answers consists of large fibers that carry proprioceptive and touch information (one of two major pathways up spinal cord) spinothalamic pathway - Answers one route from the spinal cord to the brain that carries most of the information about skin temperature and pain (smaller fibers - slower) 1. the somatosensory cortex 2. the homunculus 3. cortical magnification 4. plasticity of S1 - Answers What are the maps of the body on the cortex? two-point threshold - Answers the minimum separation between two points on the skin that when stimulated is perceived as two points grating acuity - Answers narrowest spacing of grating for which orientation can be judged raised patterns - Answers smallest sized pattern or letter that can be identified 1. less spacing between Merkel receptors 2. Cortical mechanisms - Answers The better acuity is associated with what? receptive fields - Answers area on the skin that, when stimulated, influences the firing rate of a particular neuron cortical magnification - Answers Occurs when a disproportionately large area on the cortex is activated by stimulation of a small area on the receptor surface spatial cues - Answers relatively large surface elements; (e.g., bumps & grooves) felt when the skin moves across a surface AND when it is pressed onto elements temporal cues - Answers information about the form of vibration due to movement over the surface duplex theory of texture perception - Answers The idea that texture perception is determined by both spatial and temporal cues that are detected by two types of receptors. Originally proposed by David Katz and named the "__________ __________" by Hollins. Selective Adaptation Experiment (Hollins et al.) - Answers 1. 1st adaptation condition - skin was vibrated @ 10 vibrations / sec (Hz) for 6 minutes [Meissner corpuscle] 2. 2nd adaptation condition - skin was vibrated at 250 Hz [Pacinian corpuscle] 3. After adaptation, participants ran their hand over a "standard" texture and a "test" texture. Participants indicate which texture is finer. active touch - Answers Exploring an object, usually with fingers and hands haptic perception - Answers 3D objects explored with hands passive touch - Answers When touch stimuli are applied to the skin 1. sensory system 2. motor system 3. cognitive system - Answers What systems does haptic exploration use? sensory system - Answers involved in detecting cutaneous sensations such as touch, temperature, and texture and the movements and positions of your fingers and hands motor system - Answers involved in moving the fingers and hand cognitive system - Answers involved in thinking about the information provided by the sensory and motor systems physiology behind object perception - Answers involves mechanoreceptors' responses AND cortical responses - in thalamus, S1, and frontal & parietal lobes ventral posterior nucleus - Answers receptive fields are center-surround (In thalamus) cortical neurons - Answers neurons also affected by attention neuron 1 in cortex (S1) - Answers responds best to horizontally-oriented edge presented in monkey's hand neuron 2 in cortex (S1) - Answers responds best when stimulations moves across the fingertip Nociceptors - Answers sensory receptors that enable the perception of pain in response to potentially harmful stimuli Spinothalamic - Answers coarse touch, pressure, pain, & temperature (spinal cord to thalamus) Gate Control model (Melzack & Wall) - Answers 1. Pain signals enter spinal cord from body and are transmitted to the brain 2. Additional pathways can influence the signal - acting to open or close a gate, located in the spinal cord, which determine the strength of a signal leaving the spinal cord Expectation Cognition and Pain - Answers When surgical patients are told what to expect, they request less pain medication and leave the hospital earlier. Placebos can also be effective in reducing pain. Shifting Attention Cognition and Pain - Answers virtual reality technology has been used to keep patients' attention on other stimuli than the pain-inducing stimulation Emotional Distraction Cognition and Pain - Answers subjects had to keep one of their hands immersed in cold water while they were presented with positive, neutral and negative pictures pain matrix - Answers A distributed network of brain regions, including the thalamus and anterior cingulate cortex, thought to respond to many types of pain. sensory component of pain - Answers Pain perception described with terms such as throbbing, prickly, hot, or dull. affective component of pain - Answers The emotional experience associated with pain-for example, pain described as torturing, annoying, frightful, or sickening. naloxone - Answers blocks the action of heroin by attaching itself to receptor sites usually occupied by heroin; blocks the action of endorphins in the same way as it does heroin AND blocks the effects of placebos opioids - Answers Naloxone Endorphins - Answers the brain's natural opiates empathic pain - Answers Activation of somatosensory cortex only when they receive shock themselves. Found activation in the ACC and the insula in both conditions physical-social pain overlap hypothesis - Answers proposal that pain resulting from negative social experiences is processed by some of the same neural circuitry that processes physical pain - Salty (sodium chloride) - Sour (hydrochloric acid) - Sweet (sucrose) - Bitter (quinine) - Umami (MSG) - Fats / fatty acids - Contribution of each of the four basic tastes to the tastes of KCI (potassium chloride) & NaNO3 (sodium nitrate) - Answers What are the basic qualities of taste? filiform papillae - Answers Shaped like cones & are found over the entire surface of the tongue, giving it its rough appearance fungiform papillae - Answers shaped like mushrooms and are found at the tip and sides of the tongue foliate papillae - Answers Series of folds along back of tongue on the sides circumvallate papillae - Answers shaped like flat mounds surrounded by a trench and are found at the back of the tongue filiform; 10,000 - Answers All of the papillae, except __________ papillae contain taste buds and the whole tongue contains about ____________ taste buds. in the center of the tongue - Answers Taste buds are not found ________. taste cells; taste pore - Answers Each taste bud contains 50-100 ________________ which have tips that protrude into the ________________. transduction - Answers occurs when chemicals contact receptor sites at the tips of these taste cells nucleus of the solitary tract - Answers nerve fibers from the tongue, mouth, and throat make connections in the medulla at the base of the brain (brain stem) nucleus of the solitary tract - in the medulla - thalamus - insula and frontal operculum cortex - orbitofrontal cortex - Answers What is the main pathway for taste? Distributed coding - Answers representation of an object or experience by the pattern of firing of a number of neurons specificity coding - Answers Early in taste system, receptors for sweet, bitter, & umami = protein strings that cross the taste receptor membrane seven times; Applying amiloride to the tongue blocks flow of sodium to taste receptors causes decrease in the responding of neurons in rat's brainstem that respond to salt, but not to those that respond to salty and bitter; 66 fibers in monkey's chorda tympani responding to a basic taste nontasters - Answers people who cannot detect PTC tasters - Answers people who can taste PTC Supertasters - Answers people especially sensitive to PROP and may be more sensitive to bitter substances detection threshold for odors - Answers the lowest concentration at which an odorant can be detected olfactometer - Answers an instrument for measuring the keenness of somebody's sense of smell recognition threshold of smell - Answers concentration increased by as much as a factor of 3 above detection threshold; Humans can detect as many as 1 trillion different odors, but recognizing them is more difficult; It appears that memory for odor name that is at fault. 1. Similar molecular structure = Different odor 2. Different molecular structure = Similar odor - Answers What is the puzzle for olfactory quality? [olfactory mucosa] and olfactory receptor neurons - olfactory bulb (and the glomeruli) - piriform cortex (and amygdala) - Answers What is the path for the olfactory system? olfactory mucosa - Answers Located in the upper region of the nasal cavity and is made up of the olfactory epithelium and the underlying lamina propria, connective tissue containing fibroblasts, blood vessels, Bowman's glands and bundles of fine axons from the olfactory neurons; Protects the olfactory epithelium and allows odors to dissolve so that they can be detected by Olfactory Receptor Neurons olfactory epithelium - Answers a thin layer of tissue, within the nasal cavity, that contains the receptors for smell olfactory receptor neurons - Answers - These are like rods and cones of the retina in a number of ways (350 different types) (a) contain molecules sensitive to odorants like rods and cones contain visual pigment molecules (b) made up of proteins that cross the membrane of the receptor neuron 7 times (c) sensitive to a range of specific stimuli odorant's recognition profile - Answers shows a pattern of activation of the ORN's; molecules with similar structures can smell different b/c they have different ones Cribiform plate - Answers superior surface of the ethmoid; perforated by a foramina which allows passage of the olfactory nerves, which provide sense of smell olfactory bulb - Answers the first brain structure to pick up smell information from the nose glomeruli - Answers Sites in the brain's olfactory bulb where signals from the smell receptors converge. primary olfactory cortex (piriform cortex & amygdala) - Answers located within temporal lobe; provides conscious awareness of smells Olfaction in the Environment - Answers - We rarely smell one chemical in isolation - For example coffee 100 different molecules - Plus, we can perceive the smell of coffee even when orange juice and bacon odors are also present orbitofrontal cortex - Answers assigns affective value to stimuli and experiences; E.g., Smell of mixture of isovaleric acid (smells like sweat) and cheddar cheese flavoring; If told "Cheddar cheese" it is rated as more pleasant; If told "Body odor" it is rated as less pleasant Flavor - Answers taste + olfaction