Lecture 6

Question 1

CNS

Answer 1

everything in brain and spine

Interneurons are CNS neurons whos axon stays local

Projection neuron is a CNS or PNS neuron with an axon that goes far

Question 2

PNS

Answer 2

All parts outside the brain and spinal chord

The axons of motor neurons
Which are efferent fibers from the CNS
Controlling muscles and glands

Sensory neurons
Afferent fibers info towards the CNS
These detect changes in the internal and external environments

Question 3

Peripheral nervous system

Answer 3

CNS communicates with the rest of the body via the 31 pairs of spinal nerves
12 pairs of cranial nerves

Question 4

Spinal chord

Answer 4

Long, conical structure.
Distributes motor fibers to effector organs and collects somatosensory information
Reflexes are also here

Question 5

White matter

Answer 5

Axons (myelinated)

Question 6

Dark matter

Answer 6

Cell bodies

Question 7

Somatic PNS

Answer 7

Interacts with the internal environment

Afferent and efferent

Question 8

Autonomic

Answer 8

sensation and regulation of smooth muscle. The ANS interacts with the bodies internal environment

Question 9

Sympathetic

Answer 9

Fight/flight

always active to some extent as it regulates heart rate, blood flow and the activity of body organs. When acutely stimulated, blood goes from organs to muscles to increase survival

Question 10

Parasympathetic

Answer 10

Rest digest, feed, breed

Increasing bodies energy stores (digestion)

Question 11

Hindbrain components

Answer 11

Cerebellum, pons & midbrain
Many cranial nerves come out of the pons and medulla

The primary crossing of descending motor neurons is in the hindbrain

Question 12

Medulla oblongata

Answer 12

Most caudal part of the brain stem. Collection of nuclei that regulate much autonomic functions such as heart rate that are autonomic and essential for life.

The area postreama has a pourus blood brain barrier and detects chemicals in blood. Can vomit.

Also contains part of the reticular formation which facilitates alertness and sleep.

Question 13

Pons

Answer 13

Relays info from cerebrum and cerebellum.

Also has part of the reticular formation - sleep

Also has cranial nerves, hearing, balance, taste and sensations on the face

Question 14

Cerebellum

Answer 14

Motor control

Tightly folded surface

Doesn’t initiate movement but makes it more coordinated and precise

Integrates sensory and motor information to exert a coordinating and smoothing effect on movement and cognition. Plays a role in motor learning especially when parts of the body grow and change (so necessitate adjustments in motor patterning)

Cerebellar damage = jerky movements. Excessive = cannot stand.

Question 15

Midbrain

Answer 15

Regulates aspects of hearing, vision, motivation, movement and arousal. 2 bits

Question 16

Tectum

Answer 16

Is the roof of the midbrain

Is 2 bumps on the dorsal surface of the midbrain

Top bumps are the superior colliculi - orientating toward a visual stimulus

Inferior colliculi - orientating towards an audio stimuli

Important for recognizing danger,

Question 17

Tegmentum

Answer 17

Rostral reticular formation (sleep and arousal)

Periaqueductal gray - species specific responses to pain (like running away or threatening posture)

Substancia nigra (motivation and regulation of purposeful movement (Parkinson’s)

Question 18

Copy & Paste forebrain

Answer 18

Does what the hindbrain does but via hormones instead of axons

Question 19

Hypothalamus

Answer 19

Bilateral, several nuclei which regulate hormonal systems

4 Fs, feeding, fighting, fleeing and mating

Different nuclei control temp, sleep/wake, hunger, social behaviour

Links CNS to endocrine system

Question 20

Thalamus

Answer 20

Relays sensory information to cerebellum

Also sleep/wake cycle

Lateral geniculate nucleus takes info from eye and sends it to the primary visual cortex

Medial geniculate cortex covers audio information

Question 21

Basal ganglia

Answer 21

Collection of nuclei

Regulates movement and does reinforcement learning and habit

Many neurological disorders are caused by damage here

Question 22

The limbic system

Answer 22

Cingulate cortex is a large area over the corpus callosum, Means encircling. Connects many parts of the limbic system

Hippocampus and amygdala are located in the temporal lobe of the cerebral cortex

Hippocampus - explicit memory formation

Amygdala - feeling and recognizing emotions eg fear

Fornix is a fiber bundle that carries signals between the septum/mammillary bodies (means arc)

The septum passes info too and from the hippocampus and amygdala

The mammillary bodies (part of the hypothalamus) are connected to the hippocampus and amygdala and are important for memories

Question 23

Cerebral cortex

Answer 23

6 layered structure (3 in birds and lizards). Neurons are connected such that they create columns, partially distinct functional units.

Largest site of neural integration. Attention, perception, thought, memory, language decision making and consciousness.

Question 24

Sulci

fissures

gyri

Answer 24

Small grooves (important is the central sulcus, separating the rostral and caudal divisions of the hemispheres

large grooves - longitudinal, lateral (frontal from temporal)

ridges between sulci or fissures

Question 25

frontal lobe

Answer 25

movement from primary motor cortex and planned movement via the premotor cortex

Question 26

parietal lobe

Answer 26

touch via somatosensory cortex

Question 27

occipital lobe

Answer 27

primary visual cortex

Question 28

temporal lobe

Answer 28

primary audio cortex

Question 29

Seonsory association cotec

Answer 29

Each primary sensory area has one

Perception takes place here and memory is stored there
If you had damage to the primary audio cortex and the auditory association cortex, not only could you not hear a dog barking but you could not even remember what a dog barking sounds like. Could still orientate yourself to a sound or a sight but could not perceive it. Cortical blindness/deafness.