Brain and Behavior Flashcards - Day 1

Question 1

Sudden inability to produce language - above or below FM?

Answer 1

Above

Question 2

Inability to move or feel both legs - above or below FM?

Answer 2

Below (arm, head, face, OK)

Question 3

Sensory loss of entire right side of face, arm, and leg - above or below FM?

Answer 3

Above

Question 4

Inability to walk - above or below FM?

Answer 4

Could be above or below

Question 5

Weakness that worsens in the late afternoon - above or below FM?

Answer 5

Below

Question 6

Weakness of the left face, arm, and leg - lesion is on what side of the brain?

Answer 6

Right

Question 7

Color: bone on CT

Answer 7

white

Question 8

Color: CSF on CT

Answer 8

black

Question 9

Color: grey matter on T1 MRI

Answer 9

grey

Question 10

Color: white matter on T1 MRI

Answer 10

white

Question 11

Color: CSF on T1 MRI

Answer 11

black

Question 12

Color: grey matter on T2 MRI

Answer 12

grey

Question 13

Color: white matter on T2 MRI

Answer 13

black

Question 14

Color: CSF on T2 MRI

Answer 14

white

Question 15

Lissencephaly

Answer 15

Defect of cerebral cortex; all gyral folds and sulci are missing: smooth brain

Question 16

Pachygyria

Answer 16

Broad, thick folds – gyral clefts do not extend all the way to ventricles

Question 17

Polymicrogyria

Answer 17

Too many small gyri

Question 18

Double cortex

Answer 18

gray matter lining ventricles; due to failure of neurons to migrate properly during development

Question 19

Focal MCD

Answer 19

lack of grey/white differentiation in one location

Question 20

Diencephalon

Answer 20

Olfactory lobes, hippocampus, cerebrum

Question 21

Telencephalon

Answer 21

Retina, epithalamus, thalamus, hypothalamus

Question 22

Metencephalon

Answer 22

Cerebellum, pons

Question 23

Myelencephalon

Answer 23

Medulla

Question 24

Mesencephalon

Answer 24

midbrain

Question 25

otx2

Answer 25

transcription factor essential for the formation of all anterior structures; absence of otx2 can result in anencephaly

Question 26

FGF

Answer 26

signals from anterior telencephalon, promote expression of Pax6 and repress Emx2

Question 27

Pax6 : Emx2 gradient

Answer 27

helps determine identities of neurons in the telencephalon along the AP axis; formed by mutual repression of each other's expression

Question 28

Hox genes

Answer 28

Specifies rhombomere segmental identity along the AP axis

Question 29

Anterior - posterior patterning: rhombomere identity

Answer 29

Hox genes

Question 30

Dorso-ventral patterning

Answer 30

Localized inductive cues, including sonic hedgehog (Shh) and bone morphogenic proteins (BMPs)

Question 31

Shh is expressed where?

Answer 31

Ventral midline, nearly entire length of neural tube

Question 32

holoprosencephaly

Answer 32

loss of bifurcation of forebrain, results in single holosphere; one of key defects associated with its development is loss of key Shh signaling components

Question 33

How does Shh pattern the dorsal-ventral axis?

Answer 33

Different concentrations of Shh repress expression of certain transcription factors; some pairs of TxFx are mutually repressive → leads to combinatorial output of TxFx sequence that determines cell fate along the dorsal-ventral axis

Question 34

Potency of neural crest cells

Answer 34

multipotent

Question 35

Fates of neural crest cells

Answer 35

Sensory ganglia Non-neuronal melanocytes Adrenal neuro-secretory cells Autonomic ganglia

Question 36

Inside-out maturation

Answer 36

newer neurons migrate past older neurons to assume more superficial positions; newest neurons are at the surface, applies to EXCITATORY neurons

Question 37

Inhibitory neurons: migration

Answer 37

generated in ventral telencephalon & migrate to cortex

Question 38

Failure of GABAnergic specification or migration can lead to...

Answer 38

inhibitory interneurons in cortex & epilepsy

Question 39

Guidance cues

Answer 39

Secreted and transmembrane molecules that influence axon trajectories.

Question 40

Robo-3 receptor

Answer 40

guidance cue receptor; defects in humans can lead to horizontal gaze palsy

Question 41

EphrinA

Answer 41

repellent, expressed at HIGH levels in POSTERIOR tectum; axons expressing high levels of EphA terminate in anterior positions

Question 42

EphrinB

Answer 42

attractant, expressed at HIGH levels in VENTRAL tectum; axons expressing high levels of EphB are drawn to ventral positions

Question 43

Neurotrophins

Answer 43

family of extracellular signaling molecules; promote the survival of specific neurons

Question 44

Trophic factors

Answer 44

secreted by post-synaptic cells, required for cell survival

Question 45

Nerve Growth Factor (NGF)

Answer 45

trophic factor, secreted by sympathetic targets, taken up by sympathetic nerve endings & transported back to the cell body, prevents neurons from self-destructing