into neurotrans

neuroanatomy2.md

@@ -3,6 +3,11 @@
 * Circuits that do the same kinds of things are grouped into 'systems', e.g. sensory systems and motor systems
 * Many neurons function between these systems, called associational systems. Associational systems are the most complex and least well characterized systems.
 
+<div style="font-size:0.5em;">
+2020-10-13T11:43:55-07:00
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+
 Note:
 
 Last time we learned some of the basic cellular anatomy of the nervous system. Today we will put the system in nervous system–– because nervous systems really are greater than the sum of its parts… in other words our brain is not just a blob of cells but it is the interconnections between cells, groups of cells, and brain regions that allow our fantastic feats of emergent biological computation. So lets discuss the overall the structure of the nervous system.
@@ -21,9 +26,11 @@ First of all it is a system of systems. In other words…
 
 Note:
 
+Left: movie on left illustrates where the central nervous system is in our bodies.
+
 Middle: illustrates the two top level systems of the nervous system, the CNS containing the brain and spinal cord and the PNS containing nerves and ganglia exiting the spinal cord.
 
-Right: outlines the functional hierarchy of different components or systems within the whole nervous system including relations between internal and external environment and sensory receptors in the PNS as well as skeletal muscle and smooth, cardiac muscles that the nervous system controls.
+Right: outlines the functional hierarchy of different components or systems within the whole nervous system. This includes relations between the internal and external environment with and sensory receptors in the PNS as well as the relation between skeletal muscle and smooth, cardiac muscles that the nervous system controls.
 
 *Don't worry too much about memorizing the exact details of diagrams such as this, focus on the major concepts and their relations*
 
@@ -297,9 +304,9 @@ neural tube/dorsal nerve cord: chordates (fish, amphibians, reptiles, birds, and
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 <div></div>
 
-* Dorsal column– sensory signals travels up it to the brain
+* Dorsal column– carries sensory signals up to the brain
 * Lateral columns– also called the cortico-spinal tracts. Carries signals from brain to interneurons and motor neurons in ventral horn
-* Ventral columns (sometimes called anterolateral column)– carry pain signals up and motor signals down
+* Ventral columns (sometimes called anterolateral column)– carries pain signals up and motor signals down
 
 </div>
 
@@ -313,7 +320,7 @@ Lateral columns-also called the cortico-spinal tracts.  Take info from brain and
 
 Ventral columns (sometimes called anterolateral column)- carry pain info up and motor info down.
 
-*Cervical enlargement: Gray matter expanded to incorporate more sensory input from limbs and more cell bodies for motor control of limbs*
+-Cervical enlargement: Gray matter expanded to incorporate more sensory input from limbs and more cell bodies for motor control of limbs
 
 *Rexed's laminae are cytoarchitectonic divisions of spinal cord gray matter, see Table A1* ...don't worry about knowing the lamina
 
@@ -345,7 +352,7 @@ And all information from higher order or more rostral brain structures that goes
 * Medulla– regulates blood pressure and respiration.
 * Ventral pons– pontine nuclei, relay signals from cortex to the cerebellum
 * Dorsal pons– respiration taste and sleep
-* Midbrain– auditory and visual systems, substantia nigra pars compacta (dopaminergic neurons). Deteriorates in Parkinson’s disease.
+* Midbrain– auditory and visual systems, substantia nigra pars compacta (dopaminergic neurons)
 
 </div>
 
@@ -414,8 +421,12 @@ Note:
 The tectum of the midbrain, which is latin for ‘roof’ contains the superior and inferior colliculi and is important for processing visual and auditory information as well as shaping motor commands for orienting the head and body.
 
 
+- red nucleus is part of midbrain, without a corticospinal tract it controls gait. Baby crawling controlled by red nucleus. Arm swinging while walking
+
 Ventral to the cerebral aqueduct through which cerebral spinal fluid circulates, you will find the tegmentum of the midbrain which contains the —>
 
+
+
 --
 
 ## Parkinson’s- loss of dopamine making neurons in the midbrain's substantia nigra
@@ -426,6 +437,7 @@ Ventral to the cerebral aqueduct through which cerebral spinal fluid circulates,
 
 Note:
 
+
 substantia nigra pars compacta, a nucleus containing neurons making the neurotransmitter dopamine that are important for regulating motor movements via their connections with the basal ganglia and which are devastated in parkinson’s disease.
 
 *dark appearance due to high levels of dark pigment neuromelanin in dopaminergic neurons*  
@@ -458,7 +470,7 @@ Well here is a grotesque way of convincing you that all you need to live is your
 * Two hemispheres, several lobes divided by fissures
 * Neurons in sheets, called cortex
 * Receives sensory input from spinal cord, motor info from cerebral cortex, balance info from inner ear and vestibular organs
-* Primarily used motor control, particularly in making postural adjustments and in fine-tuning movements
+* Primarily used for motor control, particularly in making postural adjustments and in fine-tuning movements
 * Essential for the coordination, planning of movements, learning motor tasks and storing this information
 
 <figure><img src="figs/ackman_mri-cerebellum_5dc7035.png" height="200px"><figcaption></figcaption></figure>
@@ -472,11 +484,14 @@ The cerebellum is located dorsal to the brainstem.
 
 It has two…
 
-Neurons are form cortical sheets.
+Neurons form cortical sheets like in the cerebral hemispheres.
 
 
 Receives…
 
+
+fyi: The MRI image is J. Ackman's brain back in 2009;)
+
 ---
 
 ## Cerebellum
@@ -556,7 +571,6 @@ Note:
 
 The thalamus is located in the middle of the brain…
 
-*red nucleus is part of midbrain, without a corticospinal tract it controls gait. Baby crawling controlled by red nucleus. Arm swinging while walking*
 
 --
 
@@ -617,6 +631,17 @@ Limbic system includes the amygdala, as well as the part of the basal ganglia, p
 
 Note:
 
+2500 sq cm in area or about 2.5 sq ft is the human cerebral cortex surface area:  
+https://academic.oup.com/cercor/article/18/10/2352/384745
+
+The little, but very compactly folded cerebellum has 80% of the surface area of cerebral cortex in humans. Compared with monkeys, there is evidence that the cerebellum went through a disproportionaly increased amount of surface area expansion during evolution than even the neocortex.
+
+
+Toro, Roberto; Perron, Michel; Pike, Bruce; Richer, Louis; Veillette, Suzanne; Pausova, Zdenka; Paus, Tomáš (2008-10-01). "Brain Size and Folding of the Human Cerebral Cortex". Cerebral Cortex. 18 (10): 2352–2357. doi:10.1093/cercor/bhm261. ISSN 1047-3211. PMID 18267953.
+
+Sereno et al. PNAS 2020:  
+https://doi.org/10.1073/pnas.2002896117
+
 
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@@ -646,15 +671,19 @@ Note:
 
 
 corpus callosum  
-: connections the cerebral hemispheres  
+: connections between the cerebral hemispheres  
 : only in placental mammals (the eutherians)  
 : absent in monotremes and marsupials and other vertebrates (e.g. birds, reptiles, amphibians and fish)  
 
-anterior commisure  
+Other routes for connections between the cerebral hemispheres
+
+anterior commissure  
 : connects temporal lobes  
 : connects both amygdala  
 : crossed projects from olfactory tracts  
 
+hippocampal commissure
+
 ---
 
 ## Laminar organization of neocortex
@@ -848,7 +877,5 @@ Note:
 
 <div><img src="figs/Neuroscience5e-Fig-A12-1R_copy_020ed62.jpg" height="315px"><figcaption>Neuroscience 5e Fig. A12</figcaption></div>
 
-<div><iframe src="https://www.youtube.com/embed/snO68aJTOpM" width="420" height="315"></iframe><figcaption>Pinky and the Brain</figcaption></div>
-
 
 Note: