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NEU 101 NOTES – MODULE 1 – ANATOMY (Flashcards)

Nervous System Basics

Afferent nerves travel toward the CNS and Efferent nerves travel away from the CNS. The somatic nervous system controls voluntary movement of skeletal muscles. The autonomic nervous system controls involuntary functions such as organ regulation, gland activity, and visceral processes. The sympathetic nervous system is responsible for the fight-or-flight response. The parasympathetic nervous system is sometimes called the rest-and-digest system.

Autonomic Nervous System: Sympathetic vs Parasympathetic Innervation (Module 1 Extra Credit notes)

The provided diagram labels how the sympathetic (solid lines) and parasympathetic (dotted lines) divisions innervate various structures such as the eye/pupils, salivary glands, larynx, bronchi, heart, stomach, liver, spleen, pancreas, kidneys, adrenal glands, sweat glands, peripheral blood vessels, hair follicles, small intestine, upper/ lower colon, rectum, bladder, uterus, genitals, meninges, and layers of the meninges (pia mater, arachnoid mater, dura mater). This illustrates that the autonomic divisions have widespread, organ-specific effects across the body, with the sympathetic system generally preparing for action and the parasympathetic system promoting maintenance and conservation of energy.

Ventricles, CSF, and Hydrocephalus

CSF stands for cerebrospinal fluid. CSF is produced by the choroid plexus. CSF is re-absorbed by arachnoid granulations (arachnoid villi). Hydrocephalus is an abnormal accumulation of CSF within the ventricles or subarachnoid space, leading to increased intracranial pressure and potential brain damage if untreated.

Directions of the Nervous System and Spinal Cord Anatomy

Contralateral means the opposite side, while ipsilateral means the same side. Grey matter is made of neuron cell bodies, while white matter is made of myelinated axons. In the brain, grey matter is on the outside (cortex). In the spinal cord, grey matter is on the inside (the butterfly-shaped region). For each spinal cord image, you would label where the grey and white matter lie and identify the side corresponding to the body’s belly button (anterior/ventral side).

Developmental Neuroanatomy (Module 1 Extra Credit notes 5)

The developing brain is divided into Prosencephalon (forebrain), Mesencephalon (midbrain), and Rhombencephalon (hindbrain). Matching terms: Prosencephalon = Forebrain; Mesencephalon = Midbrain; Rhombencephalon = Hindbrain. In the developing diagram, end A is the rostral (towards the beak) end and end B is the caudal (towards the tail) end. After-class tasks include labeling additional structures on the image to the right and detailing HINDBRAIN (Rhombencephalon) areas: Medulla is comprised mainly of ; Controls . (Note: Medulla contains cranial nerve nuclei and autonomic centers; it is involved in respiration, heart rate, and blood pressure regulation in most views. The rest of the structures in the hindbrain include the pons and cerebellum.)

Hindbrain Structures (Pons, Cerebellum, and Midbrain) and Midbrain Functions (Module 1 Extra Credit notes 6)

Pons is described as a bridge. Cerebellum contains motor coordination and is critical for timing of actions. MIDBRAIN (Mesencephalon) contains:

  • TEGMENTUM with the Reticular Formation (exists inside the and and tegmentum) and controls various autonomic and motor functions; Substantia Nigra is part of the midbrain and produces dopamine; Red Nucleus is part of the midbrain and controls some arm movements (e.g., crawling, arm-swinging). The Periaqueductal Gray Area is part of the midbrain; surrounds the aqueduct; Responsible for regulation/reduction of pain.

  • TECTUM: Superior Colliculus involved with visual orienting; Inferior Colliculus involved with hearing.
    DIENCEPHALON: Thalamus is a two-lobed structure responsible for relay and processing of sensory information to the cortex; Hypothalamus, located inferior and anterior to the thalamus, is responsible for homeostasis and autonomic/endocrine regulation.
    Label the Limbic System structures and note functions: Hippocampus for memory and spatial navigation; Amygdala for emotion; Cingulate Gyrus evaluates the goodness/badness of ongoing actions; Fornix is a major output tract of the limbic system; Septum connects limbic system to other brain areas; Mammillary Bodies are part of the limbic system and involved in memory; Olfactory Bulb is linked to olfaction and has limbic associations.

Basal Ganglia and Limbic System (Module 1 Extra Credit notes 7)

Label the unlabeled BASAL GANGLIA structures and note their functions:

  • Striatum (caudate and putamen together) is involved in task-setting and planning, and also in procedural learning and reward.

  • Caudate contains long tail-like structures; Putamen contains round structures lateral to the thalamus.

  • Globus Pallidus is a major output structure of the basal ganglia and is mostly inhibitory; it works in concert with the Substantia Nigra.

  • Nucleus Accumbens is the interface between motivation and action, processes rewards, and is implicated in drug addiction.
    After-class task: label unlabeled parts of the brain.

Brain Anatomy: Major Lobes, S1/M1, and Related Structures (Module 1 Extra Credit notes 7–11)

Hippocampus, Amygdala, Cingulate Gyrus, Fornix, Septum, Mamillary Bodies, Olfactory Bulb, Basal Forebrain, Insula, and Brodmann’s areas feature prominently in these sections. The Hippocampus is for memory and spatial navigation; the Amgydala is for emotion; the Cingulate Gyrus evaluates the ongoing actions; Fornix is a major output tract of the limbic system; Septum connects limbic structures to other brain regions; Mammillary Bodies are memory-related structures; Olfactory Bulb processes smell and has limbic associations. Basal Forebrain structures (e.g., nucleus basalis of Meynert) are tightly involved in awakeness and arousal via cholinergic projections; the Insula participates in interoception and emotion processing. Brodmann’s areas are based on cytoarchitecture (the shape of cells).
Label the unlabeled parts of the brain, including the occipital, temporal, parietal, and frontal lobes; identify S1 and M1 locations: S1 (primary somatosensory cortex) is on the postcentral gyrus in the parietal lobe; M1 (primary motor cortex) is on the precentral gyrus in the frontal lobe.

Neurons and Glia: Structure and Function (Module 1 Extra Credit notes 13–15)

NEURONS are nervous system cells that send chemical/electrical impulses to one another. Soma (cell body) is gray matter; Dendrites are shorter extensions for incoming signals; Dendritic spines are tiny protrusions from dendrites. Axon is the long extension for outgoing signals and is white matter; Axon hillock is the border between the soma and axon; Axon terminals/boutons are at the ends of axons; Myelin (myelin sheath) insulates the axon and is produced by glial cells; Nodes of Ranvier are gaps between myelin segments along the axon. Neurons contain typical organelles: Nucleus, Ribosomes, Mitochondria (which produce ATP), and other organelles like endoplasmic reticulum and Golgi apparatus. Cytosol is the fluid inside neurons; Extracellular fluid is outside the neuron.

Glia are non-neuronal cells that support neural function: Oligodendrocytes wrap axons in the CNS to form myelin; Schwann cells wrap axons in the PNS to form myelin; Astrocytes link neurons to blood supply and form the blood-brain barrier and support homeostasis; Microglia move and remove toxic materials (the CNS equivalent of immune cells).

Glia and Supporting Cells (Module 1 Extra Credit notes 15–16)

Ependymal cells line the spinal cord and ventricles, produce CSF, and their cilia help move CSF. Satellite cells wrap around cell bodies in the peripheral nervous system to protect them and regulate extracellular chemical environments.

Neurobiology: Science and Methods (Module 1 Extra Credit notes 17–19)

Science is a continuum between observation and experimentation. Observation is good because it reveals what is, but bad because it cannot prove causation. Experimentation is good because it can establish causation, but bad because it may introduce artificial conditions. Neuroscience is the scientific study of the nervous system through observation and/or experimentation.
Experiments manipulate the independent variable (IV) to observe effects on the dependent variable (DV).

Key terms:

  • In vivo = within a living organism; Ex vivo = outside a living organism but in a near-physiological state; In vitro = in a controlled environment outside a living organism.

  • Model species are organisms used to study human nervous systems because they are simpler and allow for invasive methods. Examples include certain animals; they provide valuable insights into human neuroscience.

Imaging and manipulation technologies cover structure, function, and causality:

  • Imaging cells: Microscopy/Histology (ex vivo, human or non-human) – see cellular anatomy – no big-picture view; Staining (tissue treated to highlight structures) – ex vivo; see cellular anatomy – no big-picture; CLARITY makes brain tissue transparent (ex vivo, non-human) to see cells in position but function is lost.

  • Imaging anatomy: CAT/CT Scan (X-ray-based, spinal bone and CSF; in vivo or ex vivo; non-invasive; radiation exposure risk); MRI (huge magnet aligns protons; in vivo or ex vivo; non-invasive; expensive); DTI (diffusion tensor imaging) uses MRI to examine water diffusion and white matter tracts; ex vivo or in vivo; non-invasive; expensive.

  • Imaging function: PET (radioactive substances to observe metabolism in real time); fMRI (measures blood oxygenation level-dependent signals to infer brain activity); both are in vivo; PET involves radiation exposure; fMRI is data-heavy but non-invasive.

  • Electrical/micro-scale recording: Single/Multi-Cell Recording (tiny probes record electrical signals; invasive; provides exact location of a small number of cells); ECoG (electrocorticography; surface of cortex; invasive but real-time cortical activity); EEG (electroencephalography; scalp-level signals; non-invasive; sensitive to movement artifacts); MEG (magnetoencephalography; skull-confined magnetic fields; non-invasive; expensive but good temporal resolution).

  • Optical and non-invasive surface imaging: fNIRS (functional near-infrared spectroscopy) uses light to estimate activity near the surface of the cortex; non-invasive; limited depth; relatively easy to use.

  • Manipulating the system: Electrical stimulation (electrically stimulate brain regions to observe reactions); TMS (transcranial magnetic stimulation; non-invasive but produces a temporary virtual lesion); tDCS (transcranial direct current stimulation; weak electrical currents through scalp to excite or inhibit neurons); Genetic manipulation (add/remove/edit genes; usually in non-human animals such as mice; invasive and time-intensive).

Notes on spatial and temporal resolution vary by method, with trade-offs between granularity in space and time. Practically:

  • Spatial resolution refers to how finely one can localize signals anatomically. Temporal resolution refers to how precisely one can track changes over time.

  • Different technologies offer different balances of spatial and temporal resolution, and researchers often combine methods to obtain a fuller picture of structure and function.

This set of notes mirrors the Module 1 Extra Credit content across pages 1–19, capturing definitions, anatomical structures, functional roles, and methodological approaches that underpin introductory neuroscience in NEU 101.