Biological basis of behavior: Sensation. Vision. Hearing. Smell, touch, taste, and pain. Vestibular and kinesthetic sense.

Absolute threshold

The minimum intensity of a stimulus that can be detected 50% of the time. Barely detect or no detect.

Just- noticeable difference (Difference threshold)

The smallest detectable change in a stimulus. Can you tell the difference or nah?

Weber’s law

The principle that the size of the JND is proportional to the intensity of the stimulus. If you’d a teaspoon of sugar to some tea with very little sugar, you would notice the difference, but adding the same teaspoon of sugar to a very sweet glass of tea it might not be noticeable.

Sensory adaptation

When constant exposure to a stimulus leads to decreased sensitivity over time. your senses stop noticing.

Habituation

Getting used to repeated stimulus, learning that involves a decrease in responsiveness to stimuli after repeated exposure. Your brain stops paying attention

Synesthesia

a condition where stimulation of one sensory pathway leads to involuntary experiences in a second sensory pathway.

Transduction

Happens in the retina, the retina converts light into neural signals through photoreceptors. 

Cornea

The clear, outer layer at the front of the eye. It helps focus light coming into the eye.

Pupil

It controls how much light enters the eye by getting bigger or smaller.

Lens (accommodation)

It bends (accommodates) to focus light onto the retina for clear vision.

Retina

The back of the eye where light is turned into signals. It contains special cells (rods and cones) that helps us see.

Fovea

Where vision is the sharpest, used for detailed tasks like reading.

Optic nerve

The nerve that sends visual information from the eye to the brain for processing

Rods

Detect light and are used I low-light conditions

Cones

Detect color and are concentrated in the fovea, the center of the retina. CONES SEE COLOR

Trichromatic theory 

The retina contains three types of color receptors (red, green, blue) and there combination allows us to perceive the full color spectrum

Opponent-process theory

Certain cells in the brain are stimulated by some colors and inhibited by others (e.g., red-green or blue-yellow) helping to explain afterimages.

Dichromatism 

Deficiency in two types of cones

Monochromatism

Deficiency in only one type of cone or none

Afterimages

A phenomenon known as the afterimage (a visual sensation that remains after the stimulus is removed can be explained by the opponent process theory). 

Prosopagnosia (face blindness)

People can see faces and can point out the parts but they cannot identify the persons whose face is it.

Eardrum (tympanic membrane) 

vibrates when sound waves hit it. These vibrations mark the transition from the outer ear to the middle ear and start the proccess of turning sound waves into mechanical energy.

Place theory

How we hear HIGH PITCH SOUNDS

Frequency theory

how we hear LOW PITCHED SOUNDS

Volley theory

How we hear Higher pitched sounds, especially between 1,000 Hz and 4,000 Hz)

Semicircular canals

Three fluid filled tubes located in the inner ear. Each canal is oriented in a different plane (horizontal, vertical, and diagonal) to detect different types of head movements (like tilting, spinning, or turning)

Cochlea

Snail shaped, fluid filed structure that converts the mechanical vibrations from the ossicles into electrical signals. INSIDE IT IS THE BASILAR MEMBRANE, LINED WITH HAIR CELLS.

Ossicles

Three tiny bones- The malleus (hammer), incus (anvil), and stapes (stirrup)- that amplifies the vibrations from the eardrum and transfer them to the inner ear.

Sensorineural deafness 

Damage to the cochlea or auditory nerve 

Wavelengths

measured in heartz

Amplitude

Differing loudness (the great height of soundwaves hitting Akira’s eardrum determined how loud she perceived the motorcycle to be.

Taste buds

socialized structures located in the tongue that contain taste receptors.

Taste receptors

Located within the taste buds, these detect chemicals dissolved in saliva and send signals to the brain via the gustatory pathway.

Supertasters

People with more ears buds than average, highly sensitive to certain flavors, specially bitter ones.

Nontasters

People with fewer taste buds, meaning they have a reduced sensitivity to tastes.

Mechanoreceptors 

Detect pressure and texture 

Thermoreceptors

Detect changes in temperature

Nociceptors

Detect pain (damage to tissues)

Gate control theory

suggests that the spinal cord contains a neurological “gate” that either allows or blocks pain signals to enter the brain.This suggests chronic pain can be treated both by gate-closing stimulation, such as massage and by mental activity, such as distraction.

Phantom limb sensation

Refers to the experience of feeling sensations, including pain in a limb that has been amputated.

Vestibular sense

Sense of balance and spatial coordination, orientation. It is essential for everyday actions, such as walking, standing upright, and maintaining coordination.

Kinesthetic sense

Awareness of body position and movement. It allows you to know where your body parts are without looking at them.