Biopsychology Exam 3

conversion process

Stimulation- physical changes in environment

organization- lots of data into coherent data

interpretation- identifying the data

memory and recall- past experience help evaluate and react to the data received

Sensory receptor

Nerve that responds to a stimulus internal or external by creating a nerve impulse which travels to the CNS to form a response

Mechanoreceptors

Mostly in skin for sense of touch. Can sense pressure, roughness, vibration, and stretching

Thermoreceptors

In the skin to sense temperature change that is above or below body temp

Nociceptors

perceive pain, found in internal organs and surface of the body

Photoreceptors

Detect and respond to light, found in eyes

Chemoreceptors

Respond to certain chemicals, found mostly in tastebuds and nasal passages

types of photoreceptors

Cones-allow us to see fine details in bright light

Rods-sensitivity in dim light letting us see at night

What does the fovea do?

Encodes visual information separately from tiny portions

How does peripheral vision work?

In the periphery it sacrifices detail in order to get a quick image

What happens once information leaves your eyes and enters the brain?

Project into the thalamus in a section called lateral geniculate nucleus

Primary visual cortex

Located in the occipital lobe. Processes information about color and lines

Opponent process theory of color

A comparison between the two hues not in combination

Amplitude

Intensity or loudness of sound

Timbre

Distinguishing sounds

Basilar membrane

Vibrates in response to the pressure differences produced by vibrations of the oval window

Cochlea

The inner ear where vibrations of sound are transduced into neural signals

Inner hair cells

Releases neurotransmitter glutamate to auditory nerves that then carry it to the brain where it is perceived as sound

How does the basilar membrane hear frequencies

it has different width and thickness where the narrowest and thickest area resonates at higher frequencies and the thinnest and widest resonates at lower frequencies

Medial geniculate body

Nucleus in dorsal thalamus, primary gateway for auditory info to reach the cerebral cortex

utricle and saccule

What senses head position. Composed of macula tissue (composed of hair cells surrounded by support cells)

Otolithis

A layer of calcium carbonate crystals. Like a gel on top of the hair cells (stereocilia) that slides over and bends the hair follicles when head is face down to determine exact position of the head.

Ampulla and cupula

Moves in opposite directions of head movement side to side

Semicircular canals

what senses head movement

Vestibulocochlear nerve

Where signals pass through to get to the brain stem and cerebellum for sense of balance

Olfactory receptors

Complex G protein coupled receptors. Structures that weave back and forth across membranes of olfactory cells 7 times

About 350 olfactory genes in humans

Papillae

Small bumps on the tongue

somatosensory system

Provide our brain information about our own body like touch and pain

Located all over our body from surface of skin to depth of joints

Sensory discriminatory and affective motivational

Discriminatory- to determine whether the pain is coming from a sharp or blunt object (what kind of object caused the pain)

Affective- determines if the pain came from something bad

*** also work when it comes to gentle touches***

superadditive effect

Many senses coming through at once

Superior colliculus

Multisensory convergence zone-

Feedback control

While executing an action our sensory system is receiving that information to send to our CNS to adjust movements as they are happening. Slow acting responses

Feedforward control

Movements predicted from past experience and gets better with learning

Primary motor cortex

Motor control center; needed to make voluntary movements. In the frontal lobe anterior to primary somatosensory cortex

Upper motor neurons

Also called motor cortex cells

These communicate with muscles or glands

Lower motor neurons

Found at the brain stem or spinal cord- fire up when signaled by upper motor neurons

Motor homunculus

Graphical representation of Primary Motor CortexM1 neurons map

Posterior parietal cortex

Contributes to voluntary movements

Where visual and somatosensory pathways are processed

Prefrontal cortex

In the frontal lobe

The thought process of an action. Helps determine if an action is appropriate for the situation

Premotor area

Lies anterior to primary motor cortex M1

Helps plan and organize movements

Mirror neurons

First found of monkeys.

Neurons firing as if doing the action it is observing another do

Cerebellum

Located at the ventral most part of the brain.

Contains 69 billion neurons (80% of total neurons)

Contains sensory and motor components- coordinating and planning movements

Dorsal horn

Grey matter- Relays sensory inputs to the spinal cord and brain

Where sensory nerves enter

Ventral horn

Contains motor neurons

Where motor neuron nerves exit

Motor units

Collection of fibres by a single motor neuron that makes a small unit of contraction.

Muscles have hundreds of motor units

Central pattern generators (CPG)

Ensure coordinated muscle action to create fluid movement

Neuromuscular junction (NMJ)

Where muscle fiber first responds to signaling by the motor neuron

The connection between the motor neuron and the muscle fiber to make movement

Excitation contraction coupling

Electrical signals