Chap 2- Gross Anatomy of the Central Nervous System

Which lobe contains the primary motor cortex?

Frontal lobe

What Brodmann area is the primary motor cortex?

BA 4 (precentral gyrus)

What is the function of BA 6 (secondary motor cortex)?

Movement planning (premotor & supplementary motor areas)

What are the main functions of the prefrontal cortex?

Executive functions, personality, insight, foresight, self-control, motivation

Where is Broca's area located and what is its function?

Left inferior frontal gyrus (BA 44, 45); speech production

Which lobe processes somatosensory information?

Parietal lobe

What Brodmann areas make up the primary somatosensory cortex?

BA 1, 2, 3 (postcentral gyrus)

What does the left inferior parietal lobe specialize in?

Language comprehension, reading, writing (supramarginal & angular gyri)

What does the superior parietal lobe specialize in?

Spatial orientation and attention

Which lobe contains the primary auditory cortex?

Temporal lobe

What Brodmann areas are the primary auditory cortex?

BA 41, 42

What is Wernicke's area and where is it located?

Language comprehension; posterior part of BA 22 in temporal lobe

What is the planum temporale and why is it significant?

Part of BA 22 (secondary auditory cortex); larger in left hemisphere for speech processing

What does the fusiform gyrus specialize in?

Face and word recognition

What is the function of the medial temporal lobe?

Learning and memory (includes parahippocampal gyrus)

Which lobe contains the primary visual cortex?

Occipital lobe

What Brodmann area is the primary visual cortex?

BA 17 (along calcarine fissure)

What is the function of BA 18 and 19?

Visual association cortex; higher-order visual processing (motion, shape, contour)

What is the limbic lobe?

A ring of cortex on the medial surface encircling the corpus callosum and diencephalon

What are the two main components of the limbic lobe?

Cingulate gyrus and parahippocampal gyrus

What is the limbic system?

A network of brain structures involved in emotion, memory, motivation, and olfaction

Name 5 key structures in the limbic system.

Cingulate gyrus, hippocampus, amygdala, hypothalamus, fornix, mammillary bodies (any 5)

What is the hippocampus responsible for?

Memory consolidation

What is the amygdala's primary function?

Emotion processing, especially fear

What structures make up the basal ganglia?

Caudate nucleus, putamen, globus pallidus

What is the striatum?

Caudate nucleus + putamen (input region of basal ganglia)

What is the main output structure of the basal ganglia?

Globus pallidus

What are the main functions of the basal ganglia?

Movement coordination and initiation of voluntary movement

What disorder results from dopamine deficiency in basal ganglia?

Parkinson's disease (hypokinesia)

What disorder involves degeneration of basal ganglia causing involuntary movements?

Huntington's chorea (hyperkinesia)

What is the thalamus's main role?

Sensory relay station (all senses except smell)

Which thalamic nucleus relays visual information?

Lateral geniculate nucleus (LGN)

Which thalamic nucleus relays auditory information?

Medial geniculate nucleus (MGN)

What are the main functions of the hypothalamus?

Homeostasis, autonomic/endocrine control, emotion, regulation of hunger/thirst/temperature/sleep

What are the three parts of the brainstem?

Midbrain, pons, medulla oblongata

What are the superior and inferior colliculi?

Midbrain structures; superior for visual reflexes, inferior for auditory relay

What does "pons" mean and what is its function?

"Bridge" in Latin; connects to cerebellum via cerebellar peduncles

What happens at the pyramidal decussation?

Motor fibers from precentral gyrus cross to opposite side in medulla

What are the three lobes of the cerebellum?

Anterior lobe (spinocerebellum), vestibulocerebellum, posterior lobe (cerebrocerebellum)

What is the function of the anterior cerebellum?

Muscle tone, posture, equilibrium (ipsilateral mapping)

What is the function of the vestibulocerebellum?

Balance and eye movements (input from inner ear)

What is the function of the posterior cerebellum?

Motor planning and coordination (bilateral mapping)

What are commissural fibers?

Connect corresponding cortical areas between hemispheres (e.g., corpus callosum)

How many fibers are in the corpus callosum?

300-400 million fibers

What is the arcuate fasciculus?

C-shaped fiber tract connecting Broca's and Wernicke's areas

What does Broca's aphasia cause?

Non-fluent speech but good comprehension

What does Wernicke's aphasia cause?

Fluent but nonsensical speech with poor comprehension

What are the main symptoms of Parkinson's disease?

Rigidity, tremors, bradykinesia (hypokinesia)

What is chorea?

Abnormal involuntary movements seen in Huntington's disease

What two disorders are associated with the limbic system?

Epilepsy and schizophrenia

What mnemonic helps remember Broca's area function?

"Broca's Before" → speech production comes before comprehension

What mnemonic helps remember Wernicke's area function?

"What's that mean?" → comprehension

What is the "Grand Central Station" of the brain?

Thalamus (sensory relay, except smell)

What is the "Homeostasis Headquarters"?

Hypothalamus

What is the "Movement Director"?

Basal ganglia

What is the "Emotional Memory Ring"?

Limbic system

What does BA stand for in Brodmann areas?

Brodmann Area (based on cytoarchitecture)

Who defined the Brodmann areas?

Korbinian Brodmann

What is the primary function of the cingulate gyrus?

Emotion and reward processing

What structure connects the hippocampus to mammillary bodies?

Fornix

What are mammillary bodies involved in?

Memory and learning

What is the difference between a gyrus and a sulcus?

Gyrus = ridge, Sulcus = groove

What is a deep sulcus called?

Fissure

What are association fibers?

Connect cortical areas within the same hemisphere

What is the superior longitudinal fasciculus?

Association fiber tract connecting frontal, parietal, and temporal lobes

What is the calcarine fissure?

Location of primary visual cortex (BA 17) in occipital lobe

What is the precentral gyrus?

Primary motor cortex (BA 4)

What is the postcentral gyrus?

Primary somatosensory cortex (BA 1,2,3)

What does the term "limbic" mean?

"Border" or "rim" (encircles the diencephalon)

What percentage of neurons are interneurons or projection neurons?

Over 99%

What is the role of the inferior temporal gyrus?

Visual recognition

What is unique about the planum temporale in humans?

Much larger in left hemisphere; specialized for speech processing

What brain structure is critical for memory consolidation?

Hippocampus

What brain structure is known as the "bridge to the cerebellum"?

Pons

Where does decussation of motor pathways occur?

Pyramidal decussation in medulla oblongata

What are cerebellar peduncles?

Fiber tracts connecting cerebellum to brainstem

What are the pyramids in the medulla?

Contain corticospinal (pyramidal) tracts

What is the function of the cerebral peduncles?

Contain descending motor fibers (in midbrain)

What is the role of the anterior thalamic nuclei?

Part of limbic system; relay to cingulate gyrus

How does the hypothalamus control the pituitary gland?

Neural control; regulates hormone release

What is the function of the olfactory bulbs?

Process smell input; part of limbic system

What is the function of the parahippocampal gyrus?

Part of limbic lobe; involved in memory and spatial navigation