Forebrain part 1

Question 1

Cerebral cortex (details)

Answer 1

~most complex area of the brain

~has about 20 billion neurons and 200-500 trillion synapses

Question 2

Cerebral cortex (organized)

Answer 2

~Organized functionally by regional differences and within each functional region is organized by columns and layers

Question 3

The cerebrum is divided into the ____ and ____ hemisphere

Answer 3

left and right hemispheres

Question 4

Lobes in the cerebrum

Answer 4

~frontal
~parietal
~temporal
~occipital

Question 5

Frontal Lobe- specific gyri

Answer 5

~pre-central
~superior, middle, and inferior frontal
~orbital

Question 6

Temporal Lobe- specific gyri

Answer 6

~superior, middle, and inferior temporal

~parahippocampal

Question 7

the three types of connections within the cerebral cortex and

Answer 7

~projection fibers
~association fibers
~commissural fibers

Question 8

Projection fibers

Answer 8

~connections leaving the cerebral cortex going to other structures in thee neural axis
~EX: the corticospinal and corticobulbar tracts going to the spinal cord and brain stem respectively

Question 9

Association fibers

Answer 9

~connections between adjacent areas of same hemisphere

~EX: the arcuate fasciculus between language centers of the cortex

Question 10

Commissural fibers

Answer 10

~connection between the two hemisphere

~EX: corpus callosum

Question 11

Parietal Lobe- specific gyri

Answer 11

~post-central
~superior parental
~angular
~supra-marginal

Question 12

Neocortex has _ layers

Answer 12

6

Question 13

Numbered fro, 1 (most____) to 6 (most ____)

Answer 13

1- most superficial

6-most deep; nearest deep white matter

Question 14

Each layer had unique distribution of different____

Answer 14

types of cortical neurons & inputs & outputs

Question 15

Large pyramidal cells of layer ____ have axons which form:

Answer 15

layer 5

~form the principal projection output from the cerebral cortex

Question 16

Smaller pyramidal cells of layer ____ have axons which form _______ and layer ____ form _____

Answer 16

~layer 3 have axons which form commissural output

~layer 2 pyramidal cells axons for association output fibers

Question 17

Input from outside the cerebral cortex, specifically the thalamus enter and end in the ____ layer

Answer 17

layer 4

Question 18

Input from other cortical areas both association and commissural fibers primary enter and end in neurons in layers ____

Answer 18

1, 2, 4, & 5

Question 19

Brainstem reticular activating system input into ___ layers

Answer 19

all layers

Question 20

there are ___ different histological regions

Answer 20

52 different regions

Question 21

Each region is defined by

Answer 21

~different patterns of cells in each of the layers

Question 22

Brodmanns areas

Answer 22

~roughly corresponds to functional areas

Question 23

Caveats

Answer 23

~not all individuals are the same (variation in size and shape of each Brodmann area from person to person)
~Boundaries of Brodmann areas are not distantly shown
~Brain plasticity can reshape the Brodmann regions, expanding some regions and contracting others so even for one individual these areas are continuously changing through their life

Question 24

Cortical Columns

Answer 24

~neurons of similar functions organized in the same functional cortical columns
~extend from pial surface to white matter
~within a column there is a dense interconnection of neurons between layers
~most distinct cortical columns are in the primary motor and sensory cortices

Question 25

Parts of the frontal lobe

Answer 25

``` ~Primary motor area ~Pre-motor cortex ~Supplementary motor area (SMA) ~Broca's Motor Speech ~Frontal Eye Field ~Prefrontal cortex ~Anterior cingulate gyrus ```

Question 26

Primary motor area is located

Answer 26

along the pre-central gyrus

Question 27

Primary motor area (details)

Answer 27

~Pyramidal cells here have axons which are projection fibers that form the motor tracts to contralateral spinal cord lower motor neurons (LMN) (corticospinal tract) and to contralateral brain stem lower motor neurons (corticobulbar tract) ~has somatotopic organization (body map)

Question 28

Primary motor area- somatatotopic organization

Answer 28

(motor homunculus) ~the size of the body parts in the homunculus represents the number of cortical neurons that are innervating LMN in the spinal cord or brainstem ~the greater areas of the homunculus represents a greater fine motor control of the muscles in that area ~greatest in hands and face ~least in trunk and lower extremities

Question 29

Primary motor area- lesion in this area causes..

Answer 29

A lesion to primary motor area causes voluntary paralysis of opposite side of the body and facial expression **this occurs in stroke

Question 30

Pre-motor cortex is located

Answer 30

just anterior to the primary motor cortex

Question 31

Pre-motor cortex

Answer 31

~when stimulated, the result is not single muscle contraction as with the primary motor cortex but activates groups of similar muscle (synergistic muscles)

Question 32

Supplementary motor area (SMA) is located

Answer 32

superior and medial to the pre-motor cortex

Question 33

Supplementary motor area (detail)

Answer 33

~appears to be the site of the storage of motor memory ~when movements are initiated, activity in the SMA occurs up to 120 ms before movement occurs ~suggests that the SMA may develop the motor plans that are acted upon by the primary motor cortex

Question 34

Supplementary motor area- lesion

Answer 34

~lesions to the SMA produces defects in motor planning (called apraxia) ~lesions produce the loss of memory of how to preform tasks ~this is an inability to preform tasks, not a paralysis of the muscles that produce these movements

Question 35

Broca's Motor Speech Area- location

Answer 35

anterior to the primary motor cortex | **only in left hemisphere in 90% of individuals, but in some in right hemisphere, and some bilateral

Question 36

Broca's Motor Speech Area (what does it do)

Answer 36

~devoted to the control of the muscles of the face and larynx

Question 37

Broca's Motor Speech Area (damage)

Answer 37

~damage to this area produces expressive aphasia- a paucity or lack of speech production

Question 38

Frontal Eye Field- location

Answer 38

anterior to the pre-motor cortex

Question 39

Frontal Eye Field (what does it do)

Answer 39

~produces conjugate eye movements and smooth visual pursuit | ~controls the brainstem areas which produce conjugate eye movements

Question 40

Prefrontal Cortex- location

Answer 40

rostral, inferior, and medial to the Broca's area

Question 41

Prefrontal Cortex (what does it do)

Answer 41

roles on thinking, planning, social behaviors- both cognitive and emotional responses

Question 42

Prefrontal Cortex (3 distinct areas)

Answer 42

~dorsolateral ~ventromedial ~orbitofrontal

Question 43

Prefrontal Cortex- Dorsolateral frontal cortex (what does it do)

Answer 43

~involved in analytical thinking, problem solving, keeping focus and attention, and planning

Question 44

Prefrontal Cortex- Dorsolateral frontal cortex (damage)

Answer 44

~damage to this area results in disordered thinking and disorganized behavior with an inability to maintain focus and being easily distracted

Question 45

Prefrontal Cortex- Ventromedial frontal cortex (what does it do)

Answer 45

~involved in motivation, gaining emotional pleasure form life experiences and connecting to emotions and thoughts

Question 46

Prefrontal Cortex- Ventromedial frontal cortex (damage)

Answer 46

~damage to this area produces apathy, anhedonia, flat emotional affects, inability to report preferences, hyperactivity in this area in mania and less active in clinical depression

Question 47

Prefrontal Cortex- Orbitofrontal cortex (what does it to)

Answer 47

~involved in impulse control, socially acceptable behaviors, and planning

Question 48

Prefrontal Cortex- Orbitofrontal cortex (damage)

Answer 48

~damage produces irresponsible, impulsive behavior, lack of planning, focus, and organized skills ~hyperactivity in this area is associated with OCD

Question 49

Anterior cingulate gyrus is sometimes considered part of the...

Answer 49

"limbic lobe"

Question 50

Anterior cingulate gyrus (what does it do)

Answer 50

~appears to help integrate sensation, emotions, and thought with motivation and attentiveness

Question 51

Anterior cingulate gyrus (damage)

Answer 51

~damage to this area results in feeling of apathy and aimlessness ~hyperactivity corresponds to anxiety and OCD

Question 52

Parts of the Temporal Lobe

Answer 52

``` ~Primary Auditory Cortex ~Auditory association cortex ~Wernicke's receptive speech area ~Inferotemporal cortex ~medial temporal cortex (3 parts) ```

Question 53

Primary Auditory Cortex (location)

Answer 53

~located along the medial aspect of the superior temporal gyrus ~pulling back on the parietal and frontal lobes to look into the insula only the superior temporal gyrus **surrounded by the auditory association cortex

Question 54

Primary Auditory Cortex (what does it do)

Answer 54

~tonotopically organized and maps low frequencies rostral and high frequencies more posterior

Question 55

Auditory association cortex (location)

Answer 55

~inferior, lateral, and posterior to the primary auditory cortex

Question 56

Auditory association cortex (what does it do)

Answer 56

~gives rise to our complex auditory experience, including the recognition of sounds and the complex analysis of sounds

Question 57

Wernicke's receptive speech area (location)

Answer 57

~just posterior to the auditory association area | **it is in the left hemisphere in most but can be bilateral in 5-10% of individuals

Question 58

Wernicke's receptive speech area (what does it do)

Answer 58

~important for understanding language, including written, sign, and verbal/spoken language *in the non-dominant hemisphere, this area of the posterior temporal lobe is responsible for interpretation of nonverbal language, gestures, and body language

Question 59

Wernicke's receptive speech area (damage)

Answer 59

~damage produces a highly verbal who does not understand language ~lots of words, but you cannot understand what they are saying/ lots of random words

Question 60

how is the Wernick's area connected to the Broca's motor area?

Answer 60

connected by arcuate fasciculus

Question 61

Inferotemporal Cortex (location)

Answer 61

lateral and inferior temporal lobe

Question 62

Inferotemporal Cortex (what does it do)

Answer 62

responsible for the recognition of faces, objects, and colors

Question 63

Inferotemporal Cortex (damage)

Answer 63

dames produces prosopagnosia- inability to recognize faces of familiar individuals

Question 64

Medial temporal cortex (what's in it-3)

Answer 64

~Primary olfactory cortex ~Amygdala ~Hippocampus *best seen from a mid-sagittal section of the brain

Question 65

Primary olfactory cortex

Answer 65

~damage to this area will cause anosmia- loss of sense of smell

Question 66

Amygdala (location)

Answer 66

~a group of nuclei at rostral tip of the temporal lobe

Question 67

Amygdala (what does it do)

Answer 67

~generally associated with fear and anger | ~parts that are active with any strong emotion

Question 68

rich connections with hypothalamus and amygdala produce

Answer 68

the physiological responses of strong emotion including increased heart rate, respiratory rate, and blood pressure

Question 69

Where did the name hippocampus come from?

Answer 69

named from its shape- its shaped like a sea horse

Question 70

Hippocampus (location)

Answer 70

along the ventromedial aspect of the temporal lobe

Question 71

Hippocampus (what does it do)

Answer 71

~principal function is the consolidation of memory- conversation of short-term to long-term

Question 72

Hippocampus (damage)

Answer 72

produces anterograde amnesia- inability to produce new memories