Cognitive Neuro quiz 5: touch and movement

HAPTICS

perception of fine touch and pressure

primary somatosensory cortex

the main sensory receptive area for touch

Most sensitive to touch:

• Finger tips • Face • Bottoms of the feet

Least sensitive to touch:

Legs • Back • Arms

more receptors means

more sensitive

Larger receptive fields

decreased sensitivity

More cortical area =

increased sensitivity

smaller areas of the body

take up more area in the brain

Nocioception

perception of pain and temperature

free nerve endings

respond to pain and temperature

what neurons carry fine touch and pressure information

dorsal root ganglion neurons

somatasory pathways

process stimuli received from myelinated axons within the skin, muscles, and tendons

fine touch and pressure axons ascend in the

ipsilateral spinal cord forming the dorsal spinothalamic tract

somatosensory neuron

Neuron that carries information from the skin to the spinal cord

afferent neurons

neurons that take information from the senses to the brain

efferent neurons

neurons that take information from the brain to the rest of the body

fine touch and pressure signals enter spinal cord

at the same side the touch was, all the way into the brain

dorsal spinothalamic tract

Pathway that carries fine-touch and proprioception

ventral spinothalamic tract

spinal cord to the thalamus that carries information about pain and temperature.

Unilateral damage to the spinal cord will result in the loss of ______ on the same side of the body and loss of ______ on the opposite side of the body below the site of the damage.

touch and proprioception; pain and temperature

Information from the ______ crosses to the other side of the brain in the brainstem, whereas the ______ crosses to the other side of the brain in the spinal cord.

dorsal spinothalamic tract; ventral spinothalamic tract

The ______ controls limbs and digits, whereas the ______ controls mainly trunk muscles.

lateral corticospinal tract; ventral corticospinal tract

Which part of the brain is responsible for planning and initiating movements?

frontal lobe

Axons that carry information about pain and temperature form the

ventral spinothalamic tract.

The haptic and proprioceptive axons form the:

dorsal spinothalamic tract.

Homunculus

representation of body parts in the cortex

secondary somatosensory cortex

recieves sensory info from the primary somatosensory cortex

The dorsal spinothalamic tract ascends on the ipsilateral side of the spine.

true

the ventral spinothalamic tract ascends

on the contralateral side (crosses over)
pain and temp

Pain and temperature receptors use the same pathways as touch.

false

Sensitive areas on the skin receive more area

in the somatosensory cortex

how do you drink coffee? 1-8

1. visual information is used to locate
2. frontal lobe motor area plans reach n command
3. spinal cord carries info 2 hand
4. motor neurons carry message to muscles
5. sensory receptors on fingers send message to sensory cortex saying cups been grasped
6. spinal cord carries sensory info 2 brain
7. basil ganglia judge grasp and cerebellum corrects movement errors
8. sensory cortex recieves message that cups been grasped

cervical division

breathing and heart rate;
head, neck, shoulder, hand/fingers, wrist and elbow movements

Thoracic division:

trunk stability, temperature regulation

lumbar nerves

: hip movement, knee extension, foot motion

Sacral nerves:

bowels, bladder, and sexual organs

Motor neurons in the spinal cord have their cell bodies in the dorsal root.

false: motor neurons in the spinal cord have cell bodies in the ventral

Cervical nerves aid in control of breathing and heart rate

true

Lumbar nerves control the muscles of the torso and temperature regulation of the trunk

false: thoracic not lumbar

Some reflexes are the result of communication between sensory and motor neurons in the spinal cord.

true

Cerebellum/ role

coordinating and learning skilled movements; and involved in balance

timing of movements
and maintains movement accuracy

folded more densely than cerebrum

How hard would each of these tasks be with an injured cerebellum
1) Running in a race or marathon.
2) Talking and listening to a friend.
3) Playing baseball in the park.
4) Swimming or diving in a pool.
5) Singing a song out loud.

1. very
2. low to moderate
3. very
4. very
5. low to moderate

basil ganglia/ role

voluntary movements of the limbs and body

Generates the force required for a movement

Initiates movement at the appropriate time and place

basil ganglia parts

• Globus pallidus • Substantia nigra • Subthalamic nucleus

Caudate nucleus, putamen, & nucleus accumbens (striatum)

when direct pathway is activated

the caudate/putamen inhibit the GPi which disinhibits the thalamus so it can excite the cortex

increases movement

when the indirect pathway is activated

caudate/ putamen inhibits the GPe which disinhibits the subthalamic nucleus so that it can excite the GPi which inhibits thalamus/ cortex

decreases movement

If the GPi was excited, would movement increase or decrease? Why?

movement would decrease

If the GPi was inhibited, would movement increase or decrease? Why?

increase movement

prefrontal cortex

plans movements

premotor cortex

organizes movement sequences

motor cortex

produces specific movements/ executes

damage to the premotor cortex

affects the ability to coordinate motor sequences

MIRROR NEURON

cell in the primate premotor cortex that fires when an individual observes a specific action taken by another individual

topographic organization

neural spatial representation of the body

CORTICOSPINAL TRACTS

nerve fibers connecting the cerebral cortex to the spinal cord

How will your cerebellum help you improve at darts?

it makes the necessary adjustments to keep movement accurate.

When the cortex sends information to the spine to carry out an intended movement (along corticospinal tracts), a copy is sent to the cerebellum through the inferior olive.

Sensory receptors in the body and muscles records movement and sends information back to the cerebellum through the spinocerebellar tract.

Now the cerebellum has information about what you intended to do and what actually happened. It calculates the error and then informs the cortex on how to correct the movement.

Describe how the nervous system produces the movement sequence required to catch a baseball.

visual system tracks the ball, sending information to the motor and somatosensory cortices allowing them to position the body in response to the balls trajectory

The prefrontal cortex selects the goal, (catching) and relays it to the premotor cortex where the appropriate motor sequences are chosen to achieve the goal. The premotor cortex communicates this to the primary motor cortex which directs muscles

info from cortical areas will be sent to the basal ganglia, which determines force and initiation of the movements. As the motor sequences unfold, there will be moments when movement needs to increase/decrease via activation of the direct pathway of the basal ganglia.

motor commands travel via spinal cord to innervate the muscles of the body which will execute the plans. Motor commands for the trunk will be passed along the ventral corticospinal tract and the commands for the limbs will be passed along the lateral corticospinal tract.

Another component of this will be feedback from the haptic and proprioception pathways, indicating the success or failure of the motor sequence so that corrections can be made.

In the direct pathway of the basal ganglia, the caudate/putamen inhibit the______________________ , which disinhibits the ______________________ , allowing it to excite the cortex. This will ______________________ movement.

GPi; thalamus; increase;

In the indirect pathway of the basal ganglia, the caudate/putamen inhibit the(D)______________________ , which disinhibits the (E)______________________,allowing it to excite the GPi. This will (F)______________________ movement.

(D) GPe; (E) subthalamic nucleus; (F) decrease