Last psych test

Mechanoreceptors

Sensory receptors that respond to physical touch, pressure, vibration, and stretch in the skin

Merkel receptors

Slow adapting receptors that detect find detail and texture. Very precise (small receptor fields)

Meissner corpuscles

Fast adapting receptors that detect light touch and movement across the skin

Ruffini endings

Slow adapting receptors that detect skin stretch and sustain pressure help with hand shape and grip

Pacinian corpuscles

Fast adapting, receptors that detect deep pressure and vibration large receptive fields

Receptive field

The area of skin where stimulation activates a specific neuron

Small receptive fields

Allow, precise, localization, and fine detail. Example would be fingertips.

Large receptive fields

Less precise, but detect general pressure movement

Adaptation rate

How quickly a receptor stops responding to a constant stimulus

Slow adapting receptors

Continue responding during constant stimulation. Good for pressure and shape.

Fast adapting receptors

Respond mainly to changes and good for vibration and movement

Somatosensory cortex

Brain region that processes, touch pain, temperature, and body position

S1

Primary somatosensory cortex, first processing area for body sensations

S2

Secondary somatosensory cortex, further processes, and integrate sensory info

Body map

Representation of the body in the brain

Cortical magnification

More brain space is given to sensitive areas like hands and lips

Homunculus

Distorted body map, showing exaggerated, sensitive areas

Plasticity

Brains ability to re-organize based on experience or injury

Active touch

Touch involving movements and exploration (feeling objects)

Passive touch

Touch without movement (something touches you)

Texture perception

Ability to feel surface qualities like rough or smooth

Vibration

Rapid repeated stimulation detected by receptors

Perception beyond the body

Tools can extend touch example, feeling through a stick

Pain perception

Experience of pain involving sensory and emotional components

Gate control theory

Pain can be reduced when other sensory signals like touch “close the gate”

Direct pathway

Pain signals travel from receptors to spinal cord to brain

Emotional component of pain

Pain is influenced by mood, attention and experience

Phantom limb

Feeling pain or sensation in a missing limb

Pain and brain

Pain is processed by multiple brain areas

Thalamus

Relays pain signals to the brain

Amygdala

Processes emotional response to pain

Insula

Processes, internal body awareness, and pain feelings

ACC ( interior cingulate cortex)

Processes unpleasantness of pain

Endorphins

Natural painkillers produced by the body

Multimodal pain

Pain involves sensory emotional, and cognitive factor

Taste anatomy

Structures involved in taste perception

papillae

Bumps on the tongue that contain taste buds

Fungi form papillae

Found on front of tongue contains taste buds

Foliate papillae

Located on sides of tongue contain taste, buds

Circumvallate papillae

Large papillae at back of tongue, many taste buds

Filiform papillae

Do not contain taste buds, detect texture

Taste buds

Structures that contain taste receptor cells

Basic tastes

Sweet, salty, sour, bitter umami

Sweet

Signals sugar

Salty

Detect sodium

Sour

Detect acid

Bitter

Often signals toxins

Umami

Savory taste (proteins, amino acids)

Taste as gatekeeper

Helps decide what is safe to eat

Taste genetics

Genes affect taste, sensitivity

Tasters

Can detect bitter compounds like PROP

Non-tasters

Less sensitive to bitter tastes

Super tasters

Extremely sensitive to taste, especially bitter

PROP

Chemical used to test taste sensitivity

Taste aversion

Learn learned dislike after illness

Social influences

Culture and environment shape taste preferences

Flavor

Combination of taste, smell vision and touch

Taste versus flavor

Taste equals basic detection, flavor equals full experience

Olfaction and flavor

Smell is a major part of flavor

Vision and flavor

Appearance affects taste expectations

Anosmia

Loss of smell

Anosmia affects

Food tastes bland without smell

Olfaction

Sense of smell

Odorants

Chemicals that stimulate smell receptors

Detection threshold

Smallest amount needed to detect something

Olfactory bulb

Brain structure that processes smell

Smell and development

Smell developed early in life

Olfactory sensitivity

Ability to detect odors

Newborn responses

Babies can recognize smells like their mother

Dogs versus humans

Dogs have much stronger smell abilities

Nociceptors

Pain receptors that detect damage

Free nerve endings

Detect pain, temperature and crude touch

Somatosensation

Body senses like touch, pain, and temperature

Haptic perception

Touch perception involving movement and thinking

Proprioception

Sense of body position

Kinesthesis

Sense of movement

Thermoreceptors

Detect temperature

Sensory adaptation

Reduced response to constant stimulation

Absolute threshold

Minimum stimulus detected 50% of the time

Difference threshold

Smallest detectable difference between stimuli

Two point threshold

Minimum distance to feel two touches

Low two point threshold

High sensitivity (fingertips)

High two point threshold

Low sensitivity (back, arms)