BIOPSYCH MIDTERM 1
directions in the vertebrate nervous system
Anterior (towards front/toward nose end) vs. Posterior (towards back) Also referred to as rostral v. caudal Dorsal (towards surface of the back/top of head) vs Ventral (toward surface of the chest/bottom of the head) Medial (toward midline) vs Lateral (away from midline)
the study of microscopic structure of tissues in the brain
Brain histology
Radial Glia
CNS GLIA- Migration of neurons during embryonic development
Astrocytes
CNS Glial cell, form Glia Limitans structurally support and separate neurons, provide nutrients to neurons, stimulate formation of synapses
function of tegmentum (mesencephalon - midbrain)
Complex motor behavior, motivational behavior, readiness for movement, involved in sleep, arousal, vital reflexes, etc. FLOOR
Which of the following statements defines the tripartite synapse?
Connection between neurons and astrocytes
What is the important function of the spinal cord?
Control of reflex action
Lesion techniques
Destruction of all tissue in given area, Destruction only of cell bodies, Destruction only of certain cell types
Which division of the brain includes the thalamus?
Diencephalon (forebrain)
Immunocytochemistry (concept of visualization of antibody-antigen complex)
For visualizing brain distribution of specific protein Direct labeling: antibody-bound chromogen (I AB conjugated to a chromagen) Indirect labeling: chromogen coupled to a II AB → amplification of the signal with respect to the direct marking
procedures for creating organisms that lack a particular gene under investigation
Gene knockout genetic technique
Studying cell morphology
Golgi method, electron microscopy (EM), Scanning Electron Microscopy (SEM)
Neurons
Highly specialized cells Main signaling units Communicate through electrochemical signals
arachnoid and pia together is called:
Leptomeninges
The major structural difference between the sympathetic and parasympathetic nervous system is best described as:
Long post-ganglionic axons in the sympathetic nervous system and short post-ganglionic axons in the parasympathetic nervous system
axonal conduction of action potentials
Once AP is generated it travels passively along axonal membrane--> adjacent voltage-activated sodium channels Electrical signal opens channels and Na+ ions generate AP on membrane. Continues through sodium channels until AP is triggered in all the terminal buttons
Schwann cells
PNS myelinators like oligodendrocytes
What are the 3 main differences between Neuron and Animal Cell?
Processes, Synapse, and Neurotransmitters
Describe the structure of Cerebrospinal Fluid (CSF).
Produced by choroid plexus Absorbed into large channels ('sinuses') in dura mater, then back into blood stream
Caveats (warnings) of lesion techniques
Regions of brain are massively interconnected, Change of behavior after does not necessarily indicate role of intact structure
Dorsal Horn of Spinal Cord
Sensory functions. Contains dorsal root ganglia
When someone caresses a puppy, the sensory information will travel through which structures?
Sensory neurons to the dorsal root of the spinal nerve
Immunocytochemistry - cell membrane protein
Shapes of cells can be imaged by labeling protein associated specifically with cell membrane For example, we can label the membrane-associated protein MAP2 and use immunocytochemistry to visualize cell morphology
Golgi Type II Neuron
Short/branched axon: usually interneurons
Pseudo-Unipolar Neuron
Soma close to dendrites. In PNS w/ the ganglia
steps in neurotransmission
Synthesis, Packaging, Release(Exocytosis), Receptor binding, NT Clearance
Describe the microglia:
They swallow cellular debris or the entire cell, They act as the CNS immune system, They can induce controlled cell death
T/F: The right cerebral cortex affects the contralateral muscle activity.
True.
anterograde and retrograde neuroanatomical tracing techniques
Used to trace the paths of axons. Anterograde: tracing path of axons projecting away from cell bodies located in a particular area Retrograde: tracing path of axons projecting into a particular area
parasympathetic nervous system (calming)
Vegetative, non-emergency, Cranial and Sacral, Long pregang axons, Acetylcholine
Studying cell structure
Verifying lesion damage, electrode placement, etc. Studying cell morphology Identifying cell types Labeling neurochemicals or receptors Tracing neural pathways
green fluorescent protein (gFP)
a protein that exhibits bright green fluorescence when exposed to blue light.
Neurons differ according to their functions. What are they?
afferent (sensory) & efferent (motor)
What are the advantages of myelination?
allows faster conduction velocities, space-efficient, energy-efficient
Function of the tectum (mesencephalon - midbrain)
auditory (inferior colliculi) and visual reflexes (superior colliculi) ROOF
What is the choroid plexus?
capillary network lining ventricles, comes from the pia mater, produces CSF
Action potential threshold potential
depolarization sufficient for AP to be initiated
Third Ventricle
diencephalon vertically oriented, tapers into aqueduct
synapses at which the site of neurotransmitter release and the site of neurotransmitter reception are in close proximity
directed synapses
autonomic nervous system
division of the peripheral nervous system - Vegetative system/unconscious control governs functions of the gastrointestinal tract Motor innervation of the heart, smooth muscles, glands and viscera SYMPATHETIC & PARASYMPATHETIC
somatic nervous system
division of the peripheral nervous system - voluntary control of the body's skeletal muscles Motor and sensory innervation of the whole body except viscera, smooth muscle and glands
Role of glia in neurotransmission
each astrocyte coordinates the activity of neurons in its domain astrocyte may coordinate the activity of synapses in its domain tripartite synapse
Microglia
forms the immune system of the CNS, produces anti inflammatory molecules, phagocytosis
Four methods of recording electrical activity
intracellular, extracellular, multiple-unit, invasive EEG
Blood Brain Barrier (BBB)
made of astrocytes and endothelial cells, protective and semipermeable function: Minimize the risk of irreparable brain damage
Glia
main function is to protect neurons. glue that holds the neurons together.
experimental strategy and types of studies that can be done in animals
manipulations, brain, behavior
Microdialysis technique
measures the extracellular concentration of specific neurochemicals in behaving animals can be done in vivo, not very invasive, diffusion of substances
the difference in electrical charge between the inside and outside of a cell
membrane potential
Cerebral Aqueduct
mesencephalon (midbrain)
Fourth ventricle
metencephalon and myelencephalon (hindbrain) on roof of pons and medulla, diamond shaped
chemical synapses
much more flexible than electrical, can be modulated has amplification quality
synapses at which the site of release is at some distance from the site of reception.
nondirected synapses
Which meninge is closest to the brain?
pia
What information does the dorsal horn of the spinal cord carry?
sensory
Longitudinal fissure
separates cerebral hemispheres
Lateral Fissure
separates frontal from temporal lobe
Central Fissure
splits frontal and parietal lobes
Arachnoid Trabeculae
structurally continuous between arachnoid and pia
Acetylcholine synthesis
synthesized in one step from choline
Lateral Ventricles
telencephalon, C shape
A cell structure that controls which substances can enter or leave the cell. semipermeable, analogous to BBB
the cell membrane
A membrane potential is the difference in electrical charge between
the inside and outside of a cell
Peripheral Nervous System (PNS)
the sensory (afferent) and motor (efferent) neurons that connect the central nervous system (CNS) to the rest of the body. SOMATIC and AUTONOMIC
Which of the following moves Na+ ions out of neurons:
the sodium-potassium pump
There are ____ kind(s) of spatial summation and ____kind(s) of temporal summation
three; two
Giant squid axon and Hodgkin-Huxley model and its contribution
- Giant axon from a squid placed in seawater in a recording chamber - Glass microelectrode inserted into axon - Changes in permeability dependent on membrane potential and not membrane current
Unipolar neuron
1 extension, dendrites in middle, "bush cells"
Movement of the membrane potential towards threshold EPSP= ?
AP subthreshold excitation EPSP = excitatory post synaptic potential
The occipital lobe is ______ to the frontal lobe.
Caudal
Human muscle activity is coordinated by:
Cerebellum
Cerebrum
Cortex, white matter, and basal ganglia
The Metencephalon includes the Pons. What best describes the characteristic of the Pons?
Crossing of axons from left to right, and vice versa
Karl Lashley pioneered experimental work into the cortical basis of learning and discrimination. What is the best description of his Principle of Mass Action?
Deficit in learning is proportional to amount of tissue damage
What part of the nervous system includes motor neurons that lead to skeletal muscle?
Efferent nerves of somatic nervous system (Peripheral Nervous System)
In an action potential, repolarization is due to the _____ of ____ ions.
Efflux; K+
sympathetic nervous system (arousing)
Fight or Flight, Thoracic and Lumbar. Short Pregang axons, Norepinephrine
What is NOT a component of the limbic system? Mammillary bodies Amygdala Cingulate cortex Hippocampus Hypothalamus
Hypothalamus
Acetylcholine function
In CNS- REM sleep, Learning and memory, Muscle contraction
Fluorescence and brainbow (definition and application, advantage over other labeling techniques)
Method by which individual neurons in the brain can be distinguished from neighboring neurons using fluorescent proteins Each neuron is labeled with its own distinctive color, facilitating the tracing of neural axon pathways Major contribution to the field of connectomics
Multipolar neuron
Most common. dendrites attach to soma
The autonomic nervous system controls:
Movement of muscles in the alimentary canal (gastrointestinal, digestive)
Acetylcholine distribution
Neuromuscular junction Autonomic nervous system Many synapses throughout the brain
Acetylcholine receptors
Nicotinic (ionotropic) Muscarinic (metabotropic)
What are the advantages of inactivation techniques over lesion techniques?
No "recovery of function" → function returns to normal as it was before anesthetic No damage to other areas Cell specific
In myelinated axons, ions can only pass through the axonal membrane at the:
Nodes of Ranvier
Meninges
PROTECTS CNS dura mater (outer): tough membrane. Contains sinuses. arachnoid mater (middle): web like, secures dura to Pia, creates subarachnoid space pia mater (inside): delicate, very tight to brain surface
Electron microscopy (EM) - neuroanatomical technique
Provides information about the details of neuronal structure Uses a beam of accelerated electrons as a source of illumination Has a higher resolving power than light microscopes and can reveal the structure of smaller objects
epinephrineadrenaline
Released when in stress(flight or fight), adrenaline
Labeling cell activity (activity-dependent genes)
Some genes are rapidly switched on by cellular activity, e.g., c-fos By labeling c-fos RNA or protein, we can identify activated cells
Bipolar Neuron
Special senses processing and transmission
Golgi stain technique
Staining process that only labels neurons and shows gaps between. Uses TOXIC potassium dichromate. shows random 5% of neurons
What is the function of Cerebrospinal fluid (CSF)?
Supports and cushions the brain Reservoir of hormones & nutrition for brain and spinal cord
release of neurotransmitters (exocytosis, role of Ca- ions)
Synaptic transmission is electro-chemical process: AP arrives at terminal --> Voltage-gated Ca2+channels open --> Ca2+enters cell --> Synaptic vesicles fuse with presynaptic membrane --> Exocytosis of NT
Studying brain wiring (anterograde and retrograde markers and tracing)
Tracing efferent connections (neuron inputs): anterograde labels taken up by the cell bodies and transported to axons Tracing afferent connections (neuron outputs): retrograde labels taken up by terminals and transported back to soma
CNS
brain and spinal cord Main function of our nervous system is to make us the most adaptive to the ever-changing environment Neuronal circuits are generally intermingled and perform parallel computations
What is Hydrocephalus?
build-up of CSF: blocks cerebral aqueduct
Action potential arises from:
changes in membrane's selective permeability to Na+and K+
Central canal
connects 4th ventricle to spinal cord
Ventral Horn of Spinal Cord
contains bodies of MOTOR neurons
independent vs dependent variable
independent: manipulations - environmental (reward/punishment, conditioning) or biological (drug, neuromodulation) dependent: brain or behavior
routes of drug administration (chapter 5.4)
ingest: easy, safe. unpredictable effect inhale: (via capillaries in lung)- difficult to regulate dose mucous membrane: (nose, mouth, rectum) damage to membrane!! Inject: large, rapid, predictable effect
Golgi Type I Neuron
long axon and dendrites: projection neurons
What is the function of ventricles?
production, transport, removal of CSF
Oligodendrocytes - Oligodendroglia
provide physical support and form the myelin sheath around axons in the brain, regulate ionic homeostasis, scarce, close to soma
Positron emission tomography (PET) is a valuable research tool because it
provides an image of brain function.
recording resting potential
recording pipet has a very fine tip and is filled with a high salt solution so that the pipet has very low resistance voltage measured by amplifier accurately reflects the voltage across the cell membrane Method not useful in very small cells due to pipet salt poisoning of cells
Electrophysiology
records neuronal activity intracellular vs extracellular
How are action potentials produced, and how are they conducted along the axon?
through the action of voltage-activated ion channels—ion channels that open or close in response to changes in the level of the membrane potential
electrical synapses
transmission is practically instantaneous present on neurons that are involved in some sort of "survival" AP can go both ways: postsynaptic ↔ presynaptic