Quiz #1

Question 1

• The limbic system

Answer 1

-a group of brain structures in the forebrain that affects our emotions. Involves the amygdala and hypothalamus primarily- also septum and cingulate cortex… they are connected by a system of nerve pathways to the cerebral cortex. Often referred to as the “emotional brain”.. works w/ the frontal lobes to help us think and reason.
Amygdala: influence our motivation, emotional control, fear responses, and interpretations of nonverbal, emotional expressions
Hippocampus: plays role in our eomtions, ability to remember, and ability to compare sensory info to expectations.

Question 2

• Neuroplasticity and critical periods

Answer 2

• synaptic overproduction occurs when it is highly likely that nature will provide the appropriate experience to structure the development of a particular system. .. this type of development depends on environmental input that is “experience-expectant” because it is part of the evolutionary history of the organism and occurs reliably in most situations. The timing of this particular kind of experience for the CNS to grow is very important- hence there are critical periods for such development.
• in contrast, “experience-dependent” processes do not seem to limited to critical periods but can occur throughout the lifespan.

Question 3

Neuroplasticity

Answer 3

-neuroplasticity: neurons are amazingly malleable, especially during early stages of development. In time, however, most cells become specialized for certain activity, and it is harder to reverse their operation

Question 4

• How neurotransmitters function

Answer 4

“simply put, when a neuron responds to some excitation (when it “fires”), an electrical impulse, or message, travels down the axon to the axon terminals. The sacs on the terminals containing the NTs burst and release their contents intot he space between the neurons called the “synaptic gap”

Question 5

Myelination

Answer 5

Myelination: if the message is to fire, the speed of the resulting electrical impulse is increased when glial cells wrap themselves around the axon, thus facilitating conduction. this process begins prenatally in the sensorimotor areas in the brain but happens later in other areas. White matter refers to bundles of myelinated axons while gray matter refers to bundles of cell bodies, dendrites, and unmyelinated axons

Question 6

Neural Pruning

Answer 6

-neural pruning: over next 12 years after birth, many neurons die off and many synaptic connxns would be selectively discarded. Some migrated incorrectly and failed to make proper connxns, rendering them useless. Some were rarely used and therefore discarded.
 what matters most is not how many neurons you have, but the number and strength of interconnxns. The branching points of contact that remained to constitute your brain is a unique reflection of your genetics and epigenetics, condition of prenatal period, nutrition received, and postnatal experience and environment.

Question 7

• Structure of the neuron and neural connections

Answer 7

• Structure of the neuron and neural connections
Nucleus, dendrites, cell body (soma), axon, nodes of ranvier, myelin sheath, terminal endings (buttons)
-terminal buttons contain tiny sacs of NTs
-neurons are not “wired together randomly”- they are joined via their synaptic connxns into groups called “Circuits”. Circuits are part of larger organizations of neurons, called systems, such as olfactory and visual systems. There are 2 types of neurons that populate these systems:
1. projection neurons: have axons that extend away from cell body
2. interneurons: which branch out closer to the local area