Anatomy Quiz 2 - cerebral hemispheres, cortex, subcortex, limbic system, neural communication

Central nervous system (CNS)

• Brain

• Spinal cord

Peripheral nervous system

• 31 pairs of spinal nerves

• 12 pairs cranial nerves

• Peripheral autonomic and sensory ganglia

CNS Major divisions

Cerebral hemispheres, diencephalon, brainstem, cerebellum

Diencephalon

Thalamus, hypothalamus, subthalamus

Brainstem

Midbrain, pons, medulla

Cerebral cortex

• Planning & execution of actions including speech and language

• Interpretation and moderation of sensation

Subcortex

• Supports the functions of the cortex and regulate cortical activity

• Includes basal ganglia and diencephalon

Limbic system

• Regulation of emotion

• Memory formation

Center of our ability to learn, understand!

Cerebral hemispheres purpose

Frontal lobe

• Executive functioning and motor production

• Most anterior part of the brain

• Critical for language production

• Center for consciousness

• Broca’s area

Parietal lobe

Sensory integration & information

Temporal lobe

• Auditory processing and comprehension

• Primary & secondary auditory cortex

• Wernicke’s Area

• Some hearing & visual perceptions

Occipital lobe

Visual processing

Limbic Lobe

• (Insula)

• A critical area for both sensory and motor functions

• Related to speech and language skills - but not fully understood

Sulci

• Grooves or valleys in the brain

• Fissures are very deep versions of this

Gyri

Ridges or bumps in the brain

Key cortical areas for communication• Broca’s area (44 & 45)

• Broca’s area (44 & 45)
• inferior frontal gyrus
• Wernicke’s area (22)
• Superior temporal gyrus
• Primary auditory cortex (41 & 42)
• Primary sensory cortex (2)
• Primary (4) & pre (6) motor cortex
• Primary visual cortex (17)
• Supramarginal gyrus (40)
• Angular gyrus (39)

1

Precentral gyrus

• Primary motor cortex

• Controls bodily movements

2

Central sulcus

Divides frontal and parietal lobes

3

Postcentral gyrus

• Primary sensory cortex

• Processes bodily sensations

4

Supramarginal gyrus

• Broad range of language formulation

• ^ Including semantic and phonologic processing

5

Angular gyrus

• Semantic processing

• Repetition

• Metaphor comprehension

6

Pre-occipital notch

Separates occipital and temporal lobes

7

Lateral sulcus

Separates frontal & parietal lobes from the temporal lobe

8

Heschl’s / transverse gyrus

• Responsible for the reception of auditory stimuli including:

  • Frequency

  • Location

  • Intensity

• Found in primary auditory cortex

9

Superior temporal gyrus

Associated more closely with language input than output

10

Inferior frontal gyrus

Critical for higher cognitive functions like judgement, planning, decision making, executive functioning, reasoning

11

Middle frontal gyrus

Critical for higher cognitive functions like judgement, planning, decision making, executive functioning, reasoning

12

Superior frontal gyrus

Critical for higher cognitive functions like judgement, planning, decision making, executive functioning, reasoning

13

Medial / longitudinal fissure

Separates the two hemispheres

A

Broca’s area

• Associated with speech production and articulation

• Broadmann numbers 44&45

B

Wernicke’s area

• Associated with speech comprehension

• Broadmann number 22

Basal ganglia

• a group of nuclei in the brain that are involved in a variety of functions, including motor control, cognition, and emotions

• A large network of embedded gray matter structures (= a cluster of nuclei)

  • Caudate nucleus
  • Globus pallidus
  • Putamen
  *Substantia Nigra
  *Subthalamic nucleus
  •Motor coordination
  •Pathologic conditions

Thalamus

• Largest diencephalon structure

• Sensory & motor relay center

• Consciousness & alertness

• Center of the forebrain & posterior
  to the basal ganglia

• The relay station

Subcortical structures

Responsible for important emotions such as: pleasure, mating, feeding, emotions, memory, learning, motivation, fight or flight

Basal ganglia network connections

Thalamus → cerebral cortex → Striatum → GPi

Basal ganglia functions

• Releasing desired movements and cognitive process

• Inhibiting competing or undesired movements and thoughts

Hypothalamus

• Cone-shaped structure beneath the thalamus

• Bounded by the optic chiasm

• Nonconscious regulation of bodily homeostasis and hormone secretion via the pituitary gland

Limbic systems structures

• Hippocampus

• Amygdala

• Cingulate gyrus

Neurons

Basic structural and functional unit of the nervous system

A

Dendrite

Receive signals from other cells

B

Cell body

Organizes & keeps the cells functional

C

Nucleus

Controls the entire neuron

D

Axon

Transfers signals to other cells & organs

E

Node of Ranvier

Allow diffusion of ions

F

Axon Terminal

Forms junctions with other cells

G

Schwann Cell

Produces the myelin sheath / glial cells

H

Myelin Sheath

Increases the speed of the signal

Motor neurons

(efferent)

Causes muscles to contract or glands to secret

Interneurons

• Most neurons in CNS

• Process information carried by both motor and sensory neurons

Sensory neurons

(afferent)

Carry sensory information from PNS to CNS

Glial cells

Non neural cells providing support, nutrition, and maintenance for neurons

• Astrocytes

• Microglia 

• Oligodendrocytes

• Schwann cells

Gray matter

• In CNS neural tissues

• Grayish/brownish cell bodies

• Process information

White matter

• In CNS neural tissues

• White myelin sheath (fatty covering) around axon

• Transmit information

Nerves

Cranial and spinal nerves in PNS

Ganglion

(ganglia)

Groups of neuronal cell bodies and dendrites

Pathways/tracts

Bundles of axons in the CNS

Nerves

Bundles of axons in the PNS