Sensation

Sensation

The internal state produced by our senses gathering information about the outside world.

Perception

The interpretation stage of sensation, influenced by prior knowledge, memory, and current emotional state.

Transduction

The process of converting physical energy into neural energy by receptors.

Sensory nerves

Nerves that send transduced neural energy to the brain.

Absolute threshold

The lowest level of intensity at which a person can detect a stimulus 50% of the time.

Weber's Law

The law stating that the difference threshold increases in proportion to the standard stimulus.

Frequency

The number of waves per second, which determines the pitch of a sound.

Amplitude

The height of a wave, which determines the volume of a sound.

Complexity (timbre)

The nature of a sound, such as the instruments in music.

Basilar membrane

The membrane in the ear that vibrates to different frequencies, allowing us to hear different pitches.

Place theory

The theory that different places on the basilar membrane vibrate more depending on the pitch.

Frequency theory

The theory that the rate at which hair cells are stimulated determines the pitch of a sound.

Photoreceptors

Cells in the retina that respond to light and initiate transmission of information to the brain.

Rods

Photoreceptors responsible for vision in dim light and do not provide color information.

Cones

Photoreceptors responsible for vision in bright light and provide color information.

Trichromatic Theory

The theory that color vision is based on three types of cones, each sensitive to different wavelengths of light.

Dichromatic color-blindness

A condition where a person only has two types of cones, resulting in difficulty distinguishing between certain colors.

Monochromatic color-blindness

A condition where a person only has one type of cone, resulting in seeing shades of monochrome.

Trichromatic Theory

A theory of color vision that states that there are three types of color receptors in the eye, sensitive to red, green, and blue light.

Dichromats

Individuals who have only two types of color receptors in their eyes, resulting in a limited ability to perceive colors.

Yellow

A color sensation that is supposedly experienced when both red and green color receptors are activated.

Iodopsin

A light-sensitive pigment found in the cone cells of the retina, responsible for color vision.

Opponent Process Theory

A theory of color vision that suggests that color perception is based on the activity of opposing pairs of color receptors, such as blue/yellow, red/green, and black/white.

Visual Receptor Types

Different types of cells in the retina that are responsible for detecting and transmitting visual information to the brain.

Colour Afterimages

Visual phenomena where an image persists after the original stimulus has been removed, often resulting in the perception of colors opposite to the original stimulus.

Tactile Sense

The sense of touch, which involves the detection of pressure, temperature, and pain.

Temperature Receptors

Receptors in the skin that detect changes in temperature.

Pressure Receptors

Receptors in the skin that detect changes in pressure.

Adaptation

The process by which sensory receptors become less responsive to a constant stimulus over time.

Rods and Cones

Photoreceptor cells in the retina that are responsible for detecting light and transmitting visual information to the brain.

Ganglion Cells

Cells in the retina that receive information from bipolar cells and transmit it to the brain via the optic nerve.

Optic Nerve

The nerve that carries visual information from the retina to the brain.

Optic Disk

The area on the retina where the optic nerve leaves the eye, also known as the blind spot.

Optic Chiasm

The point where the optic nerves from both eyes meet and cross over, allowing information from the left visual field to be processed by the right cerebral hemisphere and vice versa.

Thalamus

A relay station in the brain that processes and relays sensory information to the appropriate areas of the cerebral cortex.

Visual Cortex

The part of the brain located in the occipital lobe that is responsible for processing visual information.

Ganglion Cell Layer

The layer of the retina that contains ganglion cells.

Bipolar Cell Layer

The layer of the retina that contains bipolar cells.

Photoreceptor Layer

The layer of the retina that contains rods and cones.

Pain

An unpleasant sensory and emotional experience associated with actual or potential tissue damage.

Substance P

A neurotransmitter involved in the transmission of pain signals.

Endorphins

Natural pain-relieving chemicals produced by the body.

Smell

The sense of olfaction, which involves the detection and perception of odors.

Pheromones

Chemicals secreted by an organism that can elicit a physiological or behavioral response in another organism of the same species.

Olfactory Sense

The sense of smell.

Adaptation

The process by which the ability to detect odors decreases over time.

Myelin Sheath

A protective covering around nerve fibers that helps to increase the speed of nerve impulse transmission.

Olfactory Bulb

A structure located in the brain that receives signals from the olfactory receptor cells in the nose.

Olfactory Receptor Cell

A specialized cell in the nose that is responsible for detecting odors.

Olfactory Mucosa

The lining of the nasal cavity that contains olfactory receptor cells.

Taste Buds

Structures on the tongue that contain taste receptor cells.

Umami

The taste sensation associated with the amino acid glutamate, often described as savory or meaty.

Flavor

The combined sensory experience of taste, smell, texture, and other factors that contribute to the perception of food.