Basic Neuroanatomy

• Brain Organisation

  1. Forebrain (Prosencephalon)

  Telencephalon

    Cerebral Cortex (9, 10, 11, 12)

    Limbic System (13)

    Basal Nuclei

  Diencephalon

    Thalamus (7)

    Hypothalamus (8)

  2. Midbrain (Mesencephalon)(2)

  3. Hindbrain (Rhombencephalon)

  Metencephalon

    Pons (3)

    Cerebellum (1)

  Myelencephalon

    Medulla Oblongata (4)

  
• Where am I? Neuroanatomy Directions

  A) Longitudinal Axis of Forebrain

  B) Longitudinal Axis of Spinal Cord

  C) Dorsal (Superior)

  D) Ventral (Inferior)

  E) Rostral (Anterior)

  F) Caudal (Posterior)

  G) Caudal (Inferior)

  H) Caudal (Inferior)

  I) Rostral (Superior)

  J) Ventral (Anterior)

  K) Dorsal (Posterior)

  
• Neuroanatomy Planes - mri

  A) Coronal / Frontal Plane

  B) Transverse / Axial Plane

  C) Sagittal Plane

  
• What is the Telencephalon?

  A) brain

  B) telencephalon

  C) cerebral cortex

  D) limbic system

  E) basal ganglia

  F) subcortical structures

  
• Subcortical Structures: Neural structures located deep to the cerebral cortex.

  •Limbic System and Basal Ganglia
• Anatomy of the Cerebral Cortex

  •Covers Right & Left Cerebral Hemispheres

  •Grey Matter: Neural tissue with neuron cell bodies and synapses

  •Cerebral Cortex

  •Basal Ganglia

  •White Matter: Neural tissue with mostly myelinated axons

  •Landmarks:

  •Sulcus/Sulci: Crevices

  •Gyrus/Gyri: Bumps

  
• Lobes of the Brain - Frontal Lobe

  Boundaries:

  •Rostral: Frontal Pole

  •Caudal: Central Sulcus

  •Ventral: Lateral Sulcus

  
• Lobes of the Brain - Frontal Lobe

  Structures:

  1.Primary Motor Cortex / Precentral Gyrus:

  Voluntary Movement Production of Contralateral Half of Body

  
• Lobes of the Brain - Frontal Lobe

  Structures:

  2. Supplementary Motor Area:

  Complex Movement Planning, Sequencing, & Bilateral Coordination

  
• Lobes of the Brain - Frontal Lobe

  Structures:

  3. Premotor Area:

  Movement Preparation, Sensory/Spatial Guidance of Movement

  
• The Motor Cortex is Comprised of:

  •Primary Motor Cortex (1)

  •Supplementary Motor Area (2)

  •Premotor Area (3)

  
• Lobes of the Brain - Frontal Lobe

  Structures:

  4. Frontal Eye Field:

  Controls Voluntary Scanning Movements of Eye

  (Horizontal Movement)

  
• Lobes of the Brain - Frontal Lobe

  Structures:

  5. Broca’s Area:

  Motor Function of Speech

  
• Broca’s Aphasia:

  Patients Cannot Physically Form Words, Effortful Speech
• Lobes of the Brain - Frontal Lobe

  Structures:

  6. Prefrontal Cortex:

  Executive Function, Personality, Intelligence, Social Behaviour, Working Memory

  
• Lobes of the Brain - Frontal Lobe – bilateral

  Boundaries:

  •Anterior: Frontal Pole

  •Posterior: Central Sulcus

  •Inferior: Lateral Sulcus

  Structures:

  1.Primary Motor Cortex (Precentral Gyrus)

  2.Supplementary Motor Area

  3.Premotor Cortex

  4.Frontal Eye Field

  5.Broca’s Area

  6.Prefrontal Cortex

  Functions: Voluntary Movement, Executive Functions, Working Memory, Personality, Social Behaviour

  
• Lobes of the Brain - Frontal Lobe – bilateral

  A) Primary Motor Cortex (Precentral Gyrus)

  B) Supplementary Motor Area

  C) Premotor Cortex

  D) Frontal Eye Field

  E) Broca’s Area

  F) Prefrontal Cortex

  
• Frontal Lobe - Primary Motor Cortex

  Location: Precentral Gyrus

  Contralateral Control

  Somatotopic Arrangement:

  •Medial: Lower Limb

  •Lateral: Face

  
• Homunculus: Body parts are sized in proportion to motor function of a body region

  •Large Hands & Face

  •Small Limbs & Trunk

  
• Frontal Lobe - Primary Motor Cortex

  Somatotopic Arrangement:

  •Medial: Lower Limb

  •Lateral: Face

  
• Parietal Lobe

  Boundaries:

  •Rostral: Central Sulcus

  •Caudal: Parieto-Occipital Sulcus

  •Ventral: Lateral Sulcus

  
• Parietal Lobe structures:

  Primary Somatosensory Cortex / Postcentral Gyrus:

  Process Contralateral Sensory Information from Touch, Pressure, Pain, etc

  
• Parietal Lobe - Structures:

  Somatosensory Association Area:

  Receive & Integrate Different Sensory Modalities for Tactile Object Recognition & Spatial Awareness

  
• Lobes of the Brain - Parietal Lobe

  Boundaries:

  •Rostral: Central Sulcus

  •Caudal: Parieto-Occipital Sulcus

  •Ventral: Lateral Sulcus

  Structures:

  1.Primary Somatosensory Cortex (Postcentral Gyrus)

  2.Somatosensory Association Area

  Functions: Process & Interpret Somatosensory Input, Proprioception

  
• Lobes of the Brain - Parietal Lobe

  A) Primary Somatosensory Cortex (Postcentral Gyrus)

  B) Somatosensory Association Area

  
• Parietal Lobe - Primary Somatosensory Cortex

  Location: Postcentral Gyrus

  Contralateral Perception

  Somatotopic Arrangement:

  •Medial: Lower Limb

  •Lateral: Face

  (has teeth and gums unlike motor)

  
• Parietal Lobe - Primary Somatosensory Cortex

  Homunculus: Body parts are sized in proportion to sensitivity of a body region

  •Large Hands & Lips

  •Small Limbs & Trunk

  
• Motor vs. Sensory Homunculus - How are these cortices arranged?

  •Both cortices are arranged somatotopically

  
• Motor vs. Sensory Homunculus

  Do they have ipsilateral or contralateral control/perception?

  •Both cortices are contralateral control or perception

  
• Motor vs. Sensory Homunculus

  Where are these cortices located?

  •Motor is in the frontal lobe on the precentral gyrus & somatosensory is in the parietal lobe on the postcentral gyrus

  
• Motor vs. Sensory Homunculus - How are these cortices similar?

  •These cortices have similar somatotopic organization where genitals are medial and face is lateral

  
• Motor vs. Sensory Homunculus - How are these cortices different?

  •The primary somatosensory cortex includes structures like teeth not found on the primary motor cortex. The body proportions are slightly different between the cortices as the hands are much bigger on the motor homunculus and the genitals/legs/trunk are bigger on the sensory homunculus.

  
• Lobes of the Brain - Temporal Lobe

  Boundaries:

  •Rostral: Temporal Pole

  •Dorsal: Lateral Sulcus

  
• Lobes of the Brain - Temporal Lobe - structures;

  Primary Auditory Cortex:

  Receive low (anterior portion) & high (posterior portion) frequency sounds

  There is some contralateral and ipsilateral perception happening.

  we're looking at the left primary auditory cortex here, but that's going to receive information from both the right inner ear and the left inner ear.

  
• Lobes of the Brain - Temporal Lobe - Structures:

  2. Wernicke’s Area:

  Written & Spoken Language Interpretation

  
• Lobes of the Brain - Temporal Lobe

  A) Primary Auditory Cortex:

  B) Wernicke’s Area

  
• Wernicke’s Aphasia:

  Patient has fluent, but nonsensical speech.
• Lobes of the Brain - Temporal Lobe

  Boundaries:

  •Rostral: Temporal Pole

  •Dorsal: Lateral Sulcus

  Structures:

  1.Primary Auditory Cortex

  2.Wernicke’s Area

  Functions: Process auditory input, language comprehension

  
• Lobes of the Brain - Occipital Lobe

  Boundaries:

  •Rostral: Parieto-Occipital Sulcus

  •Caudal: Occipital Pole

  
• Lobes of the Brain - Occipital Lobe - Structures

  Primary Visual Cortex:

  Process Visual Information

  Contralateral perception