anatomy intro ARTICLE (mini-quiz 1)

Question 1

What is the study of brain anatomy called, and why is it important?

Answer 1

Brain anatomy is the study of the structure of the brain, crucial for understanding cognitive processes, health, and disease. It is foundational to neurocomputational models and essential for psychological theories.

Question 2

Define “neuroanatomical nomenclature.”

Answer 2

Neuroanatomical nomenclature is a standardized system of terms used to describe brain structures, established by classification principles, enabling precise communication in anatomy.

Question 3

What is descriptive neuroanatomy?

Answer 3

Descriptive neuroanatomy is the identification and labeling of different parts of the brain and spinal cord, including views from different perspectives such as the axial, coronal, and sagittal planes.

Question 4

What do the terms “axial,” “coronal,” and “sagittal” refer to in brain imaging?

Answer 4

“Axial” (horizontal) divides the brain into superior and inferior parts

“coronal” divides it into anterior and posterior parts

“sagittal” divides it into left and right sections.

Question 5

Describe the term “bilateral” in neuroanatomy.

Answer 5

“Bilateral” refers to brain areas represented in both hemispheres, indicating that a structure or function appears symmetrically on both sides.

Question 6

What is the significance of Broca’s area and its typical location?

Answer 6

Broca’s area is a region important for language production, typically located in the left hemisphere, which is an example of a unilateral representation.

Question 7

Define “connectional neuroanatomy” and its significance.

Answer 7

Connectional neuroanatomy describes pathways connecting different brain regions, including commissural, projection, and association pathways. It is vital for understanding how different areas communicate within the brain.

Question 8

What is diffusion MRI tractography?

Answer 8

Diffusion MRI tractography is a neuroimaging technique used to map white matter pathways, helping visualize the course and connections between different brain regions.

Question 9

What are commissural tracts, and give an example.

Answer 9

Commissural tracts connect the left and right hemispheres of the brain. An example is the corpus callosum.

Question 10

What are the key differences between grey and white matter?

Answer 10

Grey matter contains cell bodies and synapses, and is densely packed with neurons, while white matter primarily consists of myelinated axons connecting grey matter regions.

Question 11

Explain the function and structure of the cerebral cortex.

Answer 11

The cerebral cortex is the outer layer of the brain, involved in higher cognitive functions. It has a six-layered structure with distinct areas for specialized tasks, such as sensory and motor functions.

Question 12

What are the Brodmann areas, and why are they significant?

Answer 12

Brodmann areas are regions of the cerebral cortex identified by differences in cellular structure. They help localize specific brain functions, such as motor (Area 4) and sensory processing.

Question 13

Describe the structure and role of the basal ganglia.

Answer 13

The basal ganglia are deep-brain nuclei including the striatum (putamen and caudate nucleus), globus pallidus
, subthalamic nucleus, and substantia nigra. Motor control + reward/cognition.

Question 14

What is the role of the substantia nigra, and what disease is associated with its degeneration?

Answer 14

The substantia nigra produces dopamine, and its degeneration is a hallmark of Parkinson’s disease, leading to movement difficulties.

Question 15

Explain the purpose of cerebrospinal fluid and the ventricular system.

Answer 15

Cerebrospinal fluid, produced by the ventricular system, cushions the brain, protects against injury, and supports brain metabolism.

Question 16

Define the terms “ipsilateral” and “contralateral” in brain anatomy.

Answer 16

“Ipsilateral” refers to connections or effects on the same side of the brain

“contralateral” refers to connections crossing to the opposite hemisphere.

Question 17

What are association tracts, and what is their role?

Answer 17

Association tracts connect different areas within the same hemisphere, facilitating communication between brain regions for integrated cognitive functions.

Question 18

Describe the concept of a “neuroanatomical atlas” and its purpose.

Answer 18

A neuroanatomical atlas is a reference tool used to systematically map brain regions for studying structure and function, often used in imaging studies to localize activity or pathology.

Question 19

What does the term “neuropil” refer to?

Answer 19

Neuropil is a dense network of synapses, unmyelinated axons, and dendrites within grey matter, where intense neural processing occurs.

Question 20

What are the functional divisions of the basal ganglia?

Answer 20

The basal ganglia’s main divisions are limbic/emotional, associative (behavior), and motor.

Question 21

What is the cerebellum and where is it located?

Answer 21

The cerebellum, also called the “little brain,” is located below the occipital lobe and behind the brainstem. It maintains balance, coordinates automatic movements, and supports cognitive functions such as attention, language, and memory.

Question 22

Describe the structure and connectivity of the cerebellum.

Answer 22

The cerebellum has two hemispheres connected by the vermis and includes three lobes per hemisphere: anterior, posterior, and flocculonodular. It connects to the brainstem via the superior, middle, and inferior peduncles.

Question 23

What is connectional neuroanatomy?

Answer 23

Connectional neuroanatomy studies the brain’s network of white matter tracts that connect various regions. This includes tracts connecting the brainstem, projections, association, and commissural fibers within the cerebral hemispheres.

Question 24

Explain the role of projection fibers.

Answer 24

Projection fibers link the cerebral cortex with subcortical structures and the spinal cord. They include thalamic radiations and corticofugal fibers, connecting parts like the thalamus, putamen, and internal capsule with the cortex.

Question 25

What are association fibers, and what is their function?

Answer 25

Association fibers are white matter tracts connecting different cortical areas within the same hemisphere. They include short fibers connecting adjacent gyri and long fibers connecting different lobes, enabling intrahemispheric communication.

Question 26

Describe the superior longitudinal fasciculus.

Answer 26

The superior longitudinal fasciculus is a long association fiber connecting the frontal, temporal, and parietal lobes, facilitating communication across these regions.

Question 27

What is the corpus callosum, and what is its function?

Answer 27

The corpus callosum is the brain’s largest commissural tract, containing over 300 million axons that interconnect the two cerebral hemispheres, enabling interhemispheric communication.

Question 28

Differentiate between cytoarchitectonic and myeloarchitectonic atlases.

Answer 28

Cytoarchitectonic atlases map brain regions based on cell type and density (e.g., Brodmann’s atlas), while myeloarchitectonic atlases focus on the distribution of myelinated axons (e.g., Reil and Strasburger’s atlas).

Question 29

What are standard space atlases, and why are they useful?

Answer 29

Standard space atlases, like the Montreal Neurological Institute (MNI) template, provide a common 3D brain reference framework, facilitating comparison of functional and structural MRI studies across individuals.

Question 30

Define the term “speed-accuracy tradeoff” (SAT) in neuroanatomy.

Answer 30

The SAT refers to the behavioral balance where faster responses increase error likelihood. Anatomically, it involves pathways between the cortex and basal ganglia that adjust response thresholds for speed versus accuracy.

Question 31

Explain the striatal hypothesis in the context of SAT.

Answer 31

The striatal hypothesis suggests that excitatory inputs from the cortex to the striatum reduce inhibitory control, promoting faster but less accurate responses, relevant for behaviors emphasizing speed.

Question 32

What does the STN hypothesis propose in relation to SAT?

Answer 32

The STN (subthalamic nucleus) hypothesis posits that increased input from the cortex to the STN promotes accuracy by increasing STN activity, leading to slower, more deliberate responses.

Question 33

What are commissural fibers?

Answer 33

Commissural fibers are white matter tracts interconnecting the two cerebral hemispheres, primarily through the corpus callosum, anterior commissure, and posterior commissure, facilitating interhemispheric communication.

Question 34

How do diffusion-weighted tractography techniques contribute to neuroanatomy?

Answer 34

Diffusion-weighted tractography maps white matter fiber pathways, allowing researchers to relate functional and connectional anatomy by visualizing neural connections between regions.

Question 35

What is the purpose of neuroanatomical atlases in research?

Answer 35

Neuroanatomical atlases standardize brain structure references, supporting comparative studies by accounting for individual anatomical variability across populations in both structural and functional MRI.

Question 36

Define myeloarchitecture

Answer 36

Myeloarchitecture is the study of brain regions based on the distribution of myelinated axons, revealing patterns of white matter organization.

Question 37

What are probabilistic brain atlases, and why are they significant?

Answer 37

Probabilistic atlases capture individual differences in brain structure, offering insight into functional variability across the population, crucial for studying effects of aging, development, and disease.

Question 38

Explain the importance of ultra-high resolution MRI in neuroanatomy.

Answer 38

Ultra-high resolution MRI enables detailed visualization of small brain structures, like the STN, improving anatomical accuracy and facilitating studies of structure-function relationships in cognitive neuroscience.

Question 39

What is the difference between afferent and efferent pathways?

Answer 39

Afferent pathways conduct incoming signals to a region (e.g., sensory inputs to the brain), while efferent pathways carry outgoing signals from a region to other areas (e.g., motor outputs from the brain).

Question 40

How does individual brain variability impact neuroimaging research?

Answer 40

Individual variability means no two brains are identical, requiring adaptive atlases or standard spaces in MRI studies to accommodate diverse anatomical features for accurate analysis.

Question 41

IN CLASS MINI-QUIZ QUESTION 1:

What is descriptive neuroanatomy?

Answer 41

Study of size, shape, location, direction of brain structures and regions, the organization of parts to understand the development and purpose of the system that consists of those structures and their characteristics.

Question 42

IN CLASS MINI-QUIZ QUESTION 2:

What is sectional neuroanatomy?

Answer 42

Study of relationship between structures within brain regions, to understand function and identify areas.
(example: cortex or lobe and function)