Biological Bases of Behavior (Sensation Edition)

Sensation

process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment

Perception

process of organizing and interpreting sensory information to make sense of the world aroud us. Involved the brain’s interpretation of sensory inputs, which can be influenced by past experiences, expectations, and contexts

Transduction

conversion of sensory stimuli into neural impulses that brain can understand. Its the transformation of physical energy into electrochemical signals, enabling the brain to interpret and perceive sensory information

Absolute Threshold

minimum amount of stimulation required for a stimulus to be detected by a sensory system. represents the point at which a stimulus becomes noticeable to an individual at least 50% of the time

Just Noticeable Difference (JND)

the smallest change in a stimulus that can be detected by an individual. its the minimal difference needed for a person to perceive that a change has occurred

Weber’s Law

the perceived difference in a stimulus must be proportional to the original intensity of the stimulus. the bigger smth is the more u need to change it to notice a difference

sensory adaptation

process by which sensory receptors become less responsive to constant stimuli over time

synthesia

a condition in which stimulation of one sensory pathway leads to automatic, involuntary experiences in another sensory pathway

retina

light sensitive inner surface of eye containing photoreceptor cells that convert light into neural signals

rods

photoreceptor cells in the retina responsible for vision in low light conditins and detecting motion. provides black and white vision and are highly sensitive to light, allowing us to see in dim environments

cones

photoreceptor cells in the retina responsible for color vision and detail in bright light. enable us to perceive colors and fire visual detail, such as reading text or distinguishing between different hues

fovea

central area of the retina responsible for sharp central vision. contains a high concentration of cone cells (no rods), enabling detailed and color vision

blind spot

area on the retina where the optic nerve exits the eye, lacking photoreceptor cells. its a spot where vision is absent, as there are no light sensitive cells to detect visual stimuli

ganglion cells

neurons in the retina that receive visual information from bipolar cells and transmit it to the brain via the optic nerve. plays a crucial role in processing visual signals and relaying them to the brain for further interpretation

lens

transparent structure in the eye that focuses light onto the retina. adjusts its shape to help the eye properly refract light, enabling clear vision at different distances

accommodation

process by which the lens of the eye changes its shape to focus on objects at different distances. allows for clear vsiion of both nearby and distant objects by adjusting the curvature of the lens

nearsigntedness/myopia

common vision condition where close objects appear clea but distant objects appear blurry. occurs when the eyeball is too long or cornea is too curved, causing light to focus in front of the retina instead of on it

farsightedness/hyperopia

vision condition where distant objects are seen more clearly than the close ones. happens when eyeball is too short or cornea is too flat, causing light to focus behind the retina rather than directly on it

trichromatic theory

a theory proposing that color vision is based on three types of cone receptors, each sensitive to different wavelengths of light (red, green, and blue). brain combines signals from these cones to create the perception of a wide range of colors

opponent-process theory

theory proposing that color vision. isbased on opposing color processes (red-green, blue-yellow, and black-white). activation of one color in the pair inhibits the other, leading to the perception of color afterimages and explaining certain aspects of color vision

afterimages

visual senstaions that persist after a stimulus is removed. occurs due to temporary overstimulation of cone cells in retina, resulting in a brief perception of an inverted or complementary image

dichromatism

a type of color vision deficiency where an individual has only two types of functioning cone cells instead of the normal three. this condition typically results in difficulty distinguishing between certain colors, especially reds and greens

monochromatism

rare form of color blindness where an individual has only 1 type of functoining cone cell or none at all. results in the inability to perceive colors, seeing the world in shades of gray.

blindsight

phenomenon where individuals with damage to their visual cortex can respond to visual stimuli without consciously perceiving them. suggests that some visual processing can occur unconsciously, bypassing traditional pathways in the brain

prosopagnosia(face blindness)

a neurological condition characterized by the inability to recognize familiar faces, including one’s own face, despite intact vision and intellect

wavelength

distance between sound wave peaks. shorter ones means higher pitched sounds, while longer ones mean lower pitched sounds

amplitude

measure of the intensity or loudness of a sound wave, represented by the height of its peaks. greater one means larger sounds while lower ones mean softer sounds

pitch perception

brain’s interpretation of the frequency of sound waves, determining whether a sound is high or low in tone. higher frequencies means higher pitches while lower frequences mean lower pitches.

place theory

idea that different parts of the inner ear detect different sound frequences. high pitches are sensed near the entrance, while low pitches near the end

frequency theory

theory of pitch perceptino proposing that the frquency of a sound wave directly corresponds to the rate at which auditory nerve fibers fire. higher frequency sounds lead to faster firing rates resulting in higher perceived pitches

volley theory

theory of pitch perception proposing that groups of auditory neruons fire in rapid succession, or “volleys,” to encode the frequency of sounds above 1000 hz. allows brain to perceive pitches that exceed the firing rate of individual neurons

sound localization

the brain’s ability to determine the location of a sound source in space. relies on cues such as differences in arrival time and intensity between the ears, as well as spectral cues, to accurately locate sounds

conduction deafness

hearing impairment caused by problems with the outer or middle ear, such as damage to the ear canal, eardrum, or middle ear bones. typically result in difficulty hearing soft sounds and can often be treated medically or surgically (temporarily)

sensorineural deafness

hearing loss caused by damage to inner ear or auditory nerve . results in difficulty hearing soft sounds and understanding speech, and is often permanent. common causes include aging, exposure to loud noises, and certain medical conditions

sensory interaction

the principle that one sense can influence another, such as when smell affects taste. demonstrates how our senses work together to create our overall perception of the world

olfactory systems

responsible for smells. special receptors in the noise detect smells and send signals to the brain via the olfactory nerve. thalamus helps process this information, allowing us to identify different odors

pheromones

chemical substances released by animals, including humans, that trigger social or behavioral responses in others of the same species. play a role in communication, mating, and territorial marking

gustation

sense of taste, involving receptors on the tongue that detect different flavors. taste receptors are specialized cells located on the tongue and in the mouth that detect different tastes

supertasters

highly sensitive to taste, experiencing flavors more intensely, especially bitterness

medium tasters

have. anaverage sensitivity to taste, experiencing flavors moderatelyno

nontasters

less sensitive to taste, experiencing flavors less intensely than others

warm/cold receptors

specialized sensory neurons in the skin that detect changes in temperature. warm receptors respond to increases in temperature while cold receptors respond to decreases in temperature. they help us perceive and regulate our body’s temperature.

pain

its biopsychosocial. more difficult concept. not a sensation but an emotional response to stimuli. when pain is working in a manner consistent with tissue damage it fits the traditional understanding of teh function of pain. however, there are many instances where people could experience the same stimulus and one person could feel pain and another could experience thrill, arousal, unable to acknowledge the stimulus or even perceive pain

gate control theory

proposing that the experience of pain is modulated by a neural “gate” in the spinal cord. this gate can open to allow pain signals to be transmitted to the brain or close to block them.

phantom limb

sensation of pain or other feelins in a missing limb. occurs due to the brain’s continued perception of the limb even though its no longer there. sensations can range from tingling to intense pain and are thought to result from the process of plasticity in the somatosensory cortex following amputation

vestibular sense

sense of body orientation and movement, including balance and spatial awareness. relies on receptors in the inner ear that detects changes in head position and movement, helping to maintain stability and coordinate bodily movements

semicircular canals

fluild filled structures in the inner ears that detect rotational movements of th ehead. play a crucial role in the vestibular sense, helping to maintain balance and coordination by sending signals to the brain about changes in head position and movement

kinesthesis

sense of body movement and position, including the awareness of muscle and joint sensations. allows us to perceive. andcontrol our body’s movements, providing feedback to the brain about the position and orientation of the body parts