Neuroanatomy I

2025-09-94

Rick Gilmore

Department of Psychology

Prelude

ctdalilah (2006)

Kids Learning Tube (2015)

Today’s topics

  • Announcement
  • Warm up
  • Wrap up on functional methods
  • Anatomy of the brain

Announcement

Warm up

Which of the following is not a functional neuroscience method?

  • A. Diffusion Tensor Imaging (DTI/MRI)
  • B. functional MRI (fMRI)
  • C. Positron Emission Tomography (PET)
  • D. Single-unit recording

Which of the following is not a functional neuroscience method?

  • A. Diffusion Tensor Imaging (DTI/MRI)
  • B. functional MRI (fMRI)
  • C. Positron Emission Tomography (PET)
  • D. Single-unit recording

Which of the following methods measures electromagnetic fields?

  • A. Event-related potentials (ERP)
  • B. Electroencephalography (EEG)
  • C. Magnetoencephalography (MEG)
  • D. All of the above

Which of the following methods measures electromagnetic fields?

  • A. Event-related potentials (ERP)
  • B. Electroencephalography (EEG)
  • C. Magnetoencephalography (MEG)
  • D. All of the above

Why is fMRI an indirect measure of brain activity?

  • A. fMRI measures change in blood oxygen that stem from activity several seconds earlier
  • B. fMRI measures electrical activity of individual neurons
  • C. fMRI measures things inside the head

Why is fMRI an indirect measure of brain activity?

  • A. fMRI measures changes in blood oxygen that stem from activity several seconds earlier
  • B. fMRI measures electrical activity of individual neurons
  • C. fMRI measures things inside the head

Wrap-up on functional methods

Functional methods

Anatomy of the brain

Brain anatomy through dance

Directional terms

  • Anterior/Posterior -> front/back
  • Medial/Lateral -> inside/outside
  • Superior/Inferior -> upward/downward

Wikipedia

Directional terms

  • Dorsal/Ventral -> back-ward/belly-ward
  • Rostral/Caudal -> head-ward/tail-ward

Wikipedia

Planar (slice) terms

  • Brain is 3D but view in 2D
  • Horizontal/Axial
  • Coronal/Transverse/Frontal
  • Sagittal (from the side)

http://www.scienceteacherprogram.org/biology/chillemistudentguide1-06/brain_directions_planes_sections_directions-_small.gif

Supporting structures

Meninges

  • Dura mater
  • Arachnoid mater/membrane
  • Subarachnoid space
  • Pia mater

Clinical relevance

Q: What disease is associated with inflammation of (e.g., ‘-itis’) of the meninges?

https://www.webmd.com/children/understanding-meningitis-basics

Cerebral Ventricles

  • Lateral (1st & 2nd)
  • 3rd
  • Cerebral aqueduct
  • 4th
  • Ventricles are filled with Cerebrospinal fluid (CSF)

Clinical relevance

Hydrocephalus can occur there is a blockage in the flow of CSF through the cerebral ventricles.

https://en.wikipedia.org/wiki/Hydrocephalus

Blood Supply

  • Arteries
    • external & internal carotid; vertebral -> basilar
    • Circle of Willis
    • anterior, middle, & posterior cerebral

https://en.wikipedia.org/wiki/Cerebral_arteries

Note

The Circle of Willis helps equalize blood pressures among the ascending arteries from the heart.

Blood/brain barrier

  • Isolates CNS from blood stream
  • Tighly packed endothelial cells form blood vessel walls
  • Astrocytes (a glial cell) participate in transporting substances to the brain

Blood/brain barrier

  • Exception is Area Postrema
    • In brainstem (see AP in the figure below)
    • Blood-brain barrier thin
    • Detects toxins, evokes vomiting (emesis)

Begg & Woods (2013)

The Nervous System

  • Central Nervous System (CNS)
    • Everything encased in bone
  • Peripheral Nervous System (PNS)
    • Everything else!ent

https://en.wikipedia.org/wiki/Peripheral_nervous_system

Interactive brain atlas

Organization of the brain

Major division Ventricular Landmark Embryonic Division Structure
Forebrain Lateral Telencephalon Cerebral cortex
Basal ganglia
Hippocampus, Amygdala

Organization of the brain

Major division Ventricular Landmark Embryonic Division Structure
Third Diencephalon Thalamus
Hypothalamus
Midbrain Cerebral Aqueduct Mesencephalon Tectum, Tegmentum

Organization of the brain

Major division Ventricular Landmark Embryonic Division Structure
Hindbrain 4th Rhombencephalon Cerebellum, pons
– Medulla oblongata

Note

Some of these terms arise from the developmental stages of the human embryo.

Components of the brain

Hindbrain

  • Structures adjacent to 4th ventricle 1

Medulla oblongata

  • Fibers of passage (to/from spinal cord)
  • Cranial nerves VI-XII
  • Cardiovascular regulation
  • Muscle tone

Cerebellum

  • “Little brain”
  • Dorsal to pons
  • Movement coordination, classical conditioning (associative learning), + ???
  • 3D atlas

https://en.wikipedia.org/wiki/Cerebellum

https://en.wikipedia.org/wiki/Cerebellum

Pons

  • Bulge on brain stem
  • Neuromodulatory nuclei
  • Relay to cerebellum
  • Cranial nerve V

Midbrain

Midbrain

  • Tectum
    • Tectum -> “roof”
    • Superior colliculus (reflexive orienting of eyes, head, ears)
    • Inferior colliculus (sound/auditory processing)
  • Tegmentum
    • Tegmentum -> “floor”
    • Species-typical movement sequences (e.g., cat: hissing, pouncing)
    • Cranial nerves III, IV

Midbrain

  • Tectum
    • Tectum -> “roof”
    • Superior colliculus (reflexive orienting of eyes, head, ears)
    • Inferior colliculus (sound/auditory processing)
  • Tegmentum
    • Nuclei that release modulatory neurotransmitters (“neuromodulators”)
      • Dopamine (DA)
      • Norepinephrine (NE)
      • Serotonin (5-HT)

Pineal gland

  • Releases melatonin (hormone) into bloodstream
  • Does not inflate the muscles (sorry Descartes)

Forebrain

https://www.simplypsychology.org/forebrain-midbrain-hindbrain.html

Diencephalon (“between” brain)

  • Thalamus
  • Hypothalamus

Thalamus

  • Input to cortex
  • Functionally distinct nuclei (collection of neurons)
    • Lateral geniculate nucleus (LGN), vision
    • Medial geniculate nucleus (MGN), audition

Hypothalamus

  • Five Fs: fighting, fleeing/freezing, feeding, and reproduction
  • Controls Autonomic Nervous System (ANS)
    • Sympathetic branch
    • Parasympathetic branch

Hypothalamus

  • Controls endocrine system via pituitary gland (“master” gland)
    • Anterior pituitary (indirect release of hormones)
    • Posterior (direct release of hormones)
      • Oxytocin
      • Vasopressin

Hypothalamus

  • Regulates circadian rhythms (via Suprachiasmatic Nucleus)

https://en.wikipedia.org/wiki/Hypothalamus

Telencephalon

  • Basal (not basil!) ganglia
  • Hippocampus
  • Amygdala
  • Cerebral cortex

Basal ganglia

  • Skill and habit learning
  • Sequencing of movement
  • Example: Parkinson’s Disease

Basal ganglia

Basal ganglia

Hippocampus

  • From Greek for “sea horse”

Hippocampus

  • Immediately lateral to (inferior) lateral ventricles
  • Medial temporal lobe
  • Memories of specific facts or events, spatial locations
  • Implicated in Alzheimer’s Disease

Hippocampus

https://en.wikipedia.org/wiki/Hippocampus

Amygdala

  • “almond”-shaped
  • Influences physiological state, behavioral readiness, affect
  • NOT the fear center! (LeDoux, 2015).

Take homes

  • CNS (encased in bone) vs. PNS
  • Structures defined relative to others using specific anatomical terms

Next time

  • Neuroanatomy II – the cerebral cortex

Resources

About

This talk was produced using Quarto, using the RStudio Integrated Development Environment (IDE), version 2025.5.1.513.

The source files are in R and R Markdown, then rendered to HTML using the revealJS framework. The HTML slides are hosted in a GitHub repo and served by GitHub pages: https://psu-psychology.github.io/psych-260-2025-fall/

References

Begg, D. P., & Woods, S. C. (2013). The endocrinology of food intake. Nature Reviews. Endocrinology, 9(10), 584–597. https://doi.org/10.1038/nrendo.2013.136
ctdalilah. (2006, October). Pinky and the brain-brainstem. Youtube. Retrieved from https://www.youtube.com/watch?v=snO68aJTOpM
Kids Learning Tube. (2015, October). Human body for Kids/Brain Song/Human body systems. Youtube. Retrieved from https://www.youtube.com/watch?v=Qw8E9WnZTQk
LeDoux, J. (2015, August 10). The Amygdala Is NOT the Brain’s Fear Center. Psychology Today. Retrieved from https://www.psychologytoday.com/blog/i-got-mind-tell-you/201508/the-amygdala-is-not-the-brains-fear-center