efferent

Sneaky Kisses (A Jack Maynard imagine/oneshot)

I liveeeeeeeeee… again. It’s been a while since my last post, and I’m just going to openly admit that I’m a lazy mother effer. Sorry. 

Anyway, my brain FINALLY squeezed out some creativity and this is what resulted from that. 

Enjoy :)


“Happy Tuesday, everyone, and thanks for clicking on this new video. I promise this week’s video will be worth the click,” You stated, making a very long introduction to your weekly upload. “…because I’ll be playing the ‘What’s in my Mouth’ challenge with the one and only Jack Maynard, aka The Pretty Face, aka my boyfriend.” 

“Well that was quite the intro,” Jack commented, draping an arm around the back of your chair. “And yes, note that I’m only doing this because I was promised a head massage.”

“See, once you start dating them ladies and gents, collaborating suddenly becomes a source of bribery,” You rolled your eyes. “And to think you told me you would do it because you love me…”

Jack grinned, “I do love you,” He leaned close to quickly kiss your cheek. “Somedays I just love your massages more.”

“And with that comment, don’t take any personal offense to anything that may happen in the next few minutes,” You remarked, lightly shoving him away. “Now let’s stop sickening my viewers with our disgusting couple crap and get on with the challenge!”

Keep reading

THE NERVOUS SYSTEM

The nervous system includes all the nervous tissue in the body + the sensory organs (such as the eyes and ears). 

Nervous tissue is composed of 2 kinds of cells:

  1. neurons which transmit nervous system messages
  2. glial cells which support neurons and modify their signaling.

There are 2 major divisions of the human nervous system:

  1. the central nervous system (CNS) which consists of the brain and spinal cord
  2. the peripheral nervous system (PNS) which includes all the neural tissue outside the CNS plus the sensory organs.

The PNS has 2 divisions:

  1. afferent division which brings sensory information to the CNS
  2. efferent division which carries action (motor) commands away from the CNS to the body’s ‘effectors’ (muscles and glands).

Within the PNS’s efferent division are 2 subsystems:

  1. the somatic nervous system which provides voluntary control over skeletal muscles.
  2. the autonomic nervous system which provides involuntary regulation of smooth muscle, cardiac muscle and glands.

The autonomic system is further divided into:

  1. sympathetic division (or 'fight or flight’ response) which generally has stimulatory effects (like adrenaline).
  2. parasympathetic division (or 'rest and digest’) which generally facilitates routine maintenance activities (like digestion).

There are 3 types of neurons (cells):

  1. sensory neurons. Sensory neurons sense conditions both inside and outside the body. They convey information relating to said conditions to neurons inside the CNS.
  2. interneurons. Interneurons are located entirely within the CNS and interconnect other neurons.
  3. motor neurons. Motor neurons carry instructions from the CNS to effectors (e.g. muscles or glands).

Each neuron has multiple dendrites (through which signals travel to the neuron cell body) and a single axon (that carries signals away from the cell body to the synaptic terminals).

Glial cells produce the fat-rich myelin, which can surround neural axons and increase the speed of neural signals.

A nerve is a bundle of axons in the PNS that transmits information to/from the CNS.


Nervous system communication can be conceptualized as working through a 2-step process.

  1. signal movement goes down a neuron’s axons
  2. signal movement (from said axon) goes to a second cell across a structure known as a synapse.

A nerve signal moves from one neuron to another across a synapse. Synapse includes: 

  • a 'sending’ neuron
  • a 'receiving’ neuron
  • a synaptic cleft - a tiny gap between the two cells

A chemical called a neurotransmitter diffuses across the synaptic cleft from the sending neuron to the receiving neuron. It binds with receptors on the receiving neuron, keeping the signal going.


The spinal cord can receive input from sensory neurons (and instruct motor neurons to respond) with no input from the brain. The spinal cord also channels sensory impulses to the brain.

The spinal cord has a darker (gray matter) H-shaped central area composed mostly of the cell bodies of neurons. The lighter (white matter) peripheral area is mostly composed of axons.

The central canal of the spinal cord is filled with cerebrospinal fluid that provides the spinal cord with nutrients. Spinal nerves extend from the spinal cord to the majority of areas of the body.

  • Sensory neurons, which transmit information to the spinal cord, have their cell bodies outside the spinal cord (in the dorsal root ganglia).
  • Spinal cord motor neurons have cell bodies that lie within (the gray matter of) the spinal cord. The axons of these neurons leave the spinal cord through its ventral roots.

The dorsal and ventral roots come together (like fibers being joined in a cable) to form a spinal nerve.


Reflexes are automatic nervous system responses (triggered by specific stimuli) that help us avoid danger or preserve a stable physical state (physical equilibrium).

The neural wiring of a single reflex (called a reflex arc) start with a sensory receptor that’s run through the spinal cord to a motor neuron. This proceeds back out to an effector (once again, a muscle or gland). The brain is not involved in the reflex arc.


The sympathetic division of the autonomic nervous system is often called the fight-or-flight system because it generally prepares the body to deal with emergencies.

What does it do?

  • dilates pupils 
  • inhibits salivation 
  • accelerates the heart 
  • facilitates breathing
  • inhibits digestion
  • stimulates the release of glucose
  • secretes adrenaline and noradrenaline
  • relaxes the bladder
  • inhibits sex organs

The parasympathetic division is often called the rest-and-digest system because it conserves energy and promotes digestive activities.

What does it do?

  • constricts pupils 
  • stimulates salivation 
  • slows the heart 
  • constricts breathing 
  • stimulates digestion 
  • stimulates the gallbladder 
  • contracts the bladder 
  • stimulates sex organs

Most organs receive input from both systems.


There are 7 major regions in the adult brain:

1. Cerebrum.  The cerebrum has a thin outer layer of gray matter - the cerebral cortex - that surrounds a much larger area of cerebral white matter.

Differing portions of the cerebral cortex play a central role in processing sensory information and in carrying out almost all of our conscious mental activities.

2. Cerebellum. The cerebellum refines bodily movement and balance, based on sensory inputs. 

3. Thalamus. The thalamus receives most of the body’s sensory information and then transfers it to different regions of the cerebral cortex (for processing). 

4. Hypothalamus. The hypothalamus is integral to regulating drives and maintaining homeostasis - partly through its regulation of hormonal release.

The brainstem is a collective term containing:

  • 5. Midbrain. The midbrain helps maintain muscle tone and posture.
  • 6. Pons. The pons primarily relays messages between the cerebrum and the cerebellum.
  • 7. Medulla oblongata. The medulla oblongata helps regulate involuntary functions such as breathing and digestion. When people are ‘braindead’, only their medulla oblongata is left functioning.

All human senses operate through cells called sensory receptors. Sensory receptors respond to stimuli (changes in the cells environment).

The sensory receptors transform the responses into stimuli - electrical signals - that travel through action potentials.

Signals from every sense (except smell!) are routed through the brain’s thalamus and then to specific areas of the cerebral cortex.

The sense of touch works through a variety of sensory receptors that distinguish qualities such as light or heavy pressure, new or ongoing contact, texture, etc.

In some sensory cells, the stretching of their outer membrane prompts an influx of ions that results in the initiation of a nerve signal.


Our sense of smell (or olfaction) works through a set of sensory receptors whose dendrites extend into the nasal passages.

Odorants - which are molecules that have identifiable smells - bind with hair-like extensions (cilia) of dendrites, resulting in a nerve signal to the brain.

The higher processing centers of the brain distinguish these odorants by sensing unique groups of neurons that fire in connection with given odorants.

  • humans have 340 - 380 different receptors.
  • dogs have about 1000 different receptors.
  • rats have about 1, 500 different receptors.

Our sense of taste works through a group of taste cells, located in taste buds near the surface of the tongue. The taste cells have receptors that bind to ‘tastants’ or molecules of food that elicit different tastes.

A given taste cell can respond through any 4 to 6 chemical signaling routes that correspond to the basic tastes of sweet, sour, salty, bitter and the possible fifth and sixth tastes of umami and calcium.

The neurons that receive input from taste cells vary in their response to different tastants. The brain makes sense of the pattern of input it gets from these neurons, thus yielding the large number of tastes we experience.


Our sense of hearing is based on the fact that vibrations result in 'waves’ of air molecules that are more (and less) compressed than the ambient air around them.

These waves of compression bump up against our eardrums (or tympanic membranes) which in turn vibrate; this initiates a chain of vibrations that ends in the fluid-filled cochlea of the inner ear.

'Hair cells’ in the cochlea have ion channels that open and close in response to this vibration, resulting in nerve signals to the brain.


In vision, light enters the eye through the cornea and then passes through the lens on its way to the retina (at the back of the eye).

Light is bent (or refracted) by the cornea and the lens in such a way that it ends up as a tiny, sharply focused image on the retina.

Light signals are converted to nervous system signals by cells in the retina called photoreceptors, which come in 2 varieties: 

  1. rods.  Rods function in dim light but are not sensitive to color.
  2. cones.  Cones function best in bright light but are sensitive to color.

These photoreceptors have pigments embedded in membranes within them.

Vision signals travel from photoreceptors through two sets of adjoining cells (the latter of which have axons that come together to form the body’s optic nerves).

When light strikes a pigment, it changes the pigment shape in a way that prompts a cascade of chemical reactions that result in neurotransmitter release being inhibited between the rod or cone and its adjoining connecting cell. The lack of release sends the signal: ‘photoreceptor stimulated here’.

The brain doesn’t passively record visual information; it constructs images as much as it records them.

The visual perception operates through a series of genetically based 'rules’ that allow us to quickly make sense of what we perceive.

Viva Las VAGUS…An Overview of Cranial Nerve X

X GON GIVE IT TO YA, okay that’s the last of my puns, now back to neuroscience. The Vagus nerve is the most expansive cranial nerve with a diverse array of both motor and sensory functions. The nuclei of the Vagus nerve lie in the rostral medulla, about at the level of the olivary nucleus. The Vagus nerve transmits motor output from its motor nucleus (the Nucleus Ambiguus that it shares with IX), receives gustatory impulses from the epiglottis in the solitary tract nucleus, transmits parasympathetic innervation via the dorsal nucleus of the Vagus, and receives sensory impulses from the auricular branch (the auricle and external auditory canal) and enteroceptive afferents in the Trigeminal nuclei. The motor nucleus of the Vagus is innervated by the corticobulbar tract bilaterally, and transmits efferent signals to the cricothyroid, the levator veli palatini (which raises the soft palate in conjunction with the Trigeminal’s tensor veli palatini), the salpingopharyngeus, the palatoglossus, the palatopharyngeus, the superior and inferior pharyngeal constrictors, the musculature of the larynx, and the contractile tissues of the bronchi, trachea, and bronchioles. The dorsal nucleus of the Vagus receives bilateral innervation from the Diencephalon via the diencephalobulbar tract and transmits parasympathetic innervation to all the organs and glands below the neck to ⅔’s of the transverse colon, except for the adrenal gland. The dorsal nucleus provides secretomotor efferents to the secretory tissues of the digestive tract, such as the pancreas and the stomach, inhibition to the cardiac muscle to slow heartbeat, and to the intestines to promote peristalsis. The sensory nuclei of the Vagus( aka the trigeminal nuclei) receive epicritic sensation from the auricular branch serving parts of the ear (which go to the principal or spinal nucleus of the trigeminal depending on the sensory modality), while the enteroceptive afferents from the mucosal membranes of the trachea, larynx, lungs, bronchi, esophagus, stomach, and the rest of the glands and organs below the neck are protopathic. These afferents mediate reflexive sneezing and coughing, heart beat modulation, and the sensation of hunger. This is a very brief treatment, that doesn’t really cover the entirety of synapsing in the superior and inferior ganglion of the Vagus nerve, as well as its reflexive pathways but if I did you would probably all Lose your minds, Up in Here, Up in Here( last one I promise).

NS

Shorts weather and Clean & Jerks

Basically today proved that 15.1a was a fluke. Totally a fluke.

Squat cleans and split jerks for OLY class.

85# x2

Singles at 105-125-135-145-155X-155-165XXX jerks-135-145#

All my cleans felt great, which is a relief since I have done full cleans in FOREVER. (Booty is gone I tell you.)

Noodle arms all day on the jerks. My left shoulder is slow locking out - probably after yesterday’s debauchery. I couldn’t get low enough on 165# to stabilize a lock out. M effer. How did I do it during the opens? How can I find that adrenaline again?

However, that was a power clean. I find it hard to catch my breath after a full clean to get a solid jerk. I want a day to work heavy jerks. Come on coach!

Then we did Filthy 50 - see previous post.

22:30 rxd

(2:36 PR from 12/2013 which was done with SU)

Now I am enjoying this crazy thing called sunshine. Watch out, pasty legs be gone!

‘Love is a drug,’ it is said,
making Cupid a pusher too young to be prosecuted.
I believe it, for I’ve felt the tsunami
strike of chemicals flood my brain:
adrenaline quickening my pulse,
and stealing the oxygen so I could inhale only you;
dopamine causing every efferent nerve fibre
to tingle at your proximity;
and serotonin leaving me with no taste for food -
I was sated by constant thoughts of you.
Even if it is a drug, it feels pure,
and somehow right to wallow in it,
let it consume us,
and want for these feelings to never stop.

But they also say:
‘It’s all fun and games until somebody gets hurt’.
What else can we expect from a little boy
wielding a bow and arrow
who was never taught to play gently?
Because after the high of initial infatuation
we have to come down,
and are left depleted and bereft.
Our bodies scream out for another dose of our beloveds,
and we want more, more, more,
until they can no longer satisfy our cravings.
So we leave in search of something different,
all to dull the pain of a thousand unspoken heartaches.

Now, I’ve both had love, and been without.
And what I want to know is, if love is a drug
why haven’t chemists discovered
a way to pop it, sniff it, or mainline it?
Because I need another hit.

Let's Reconsider Our Aesthetic Stance

“Efferent” vs. “Aesthetic”


First we must define the above terms. The efferent stance refers to reading and taking the direct meaning from it. Examples would be directions to follow, conclusions to be retained, information to be retained or acted upon after reading the text. Aesthetic stance on the other hand is when you pay attention to the feelings, images, emotions, sounds, or rhymes of words or tensions of the text.

Literature and Life

I try to relate the above two not just to literature, but also to life in general. You carry away with you what you learn but actually understanding and knowing why is a complete whole step. That’s why the efferent stance is unchanged (unless you take nothing from an experience) and the aesthetic stance is ever changing. Most things fall between efferent and aesthetics. But bringing your past and present feelings, ideas, beliefs, etc. will make your self expression better.

Reconsider Your Aesthetic Stance

Always know that your aesthetic stance is ever changing and I hope things will occur to challenge it. It can remain the same or it can broaden or narrow. Just know that it will reflect onto others. So when things don’t seem quite like you would want them, acknowledge your efferent stance but reconsider your aesthetic stance.

If you’ve got time to spare, check out the book “The Giver”.

.e/p

youtube

It is now time to meet the system that helps your crazy brain stay in touch with the outside world. We follow up last week’s tour of the central nervous system with a look at your peripheral nervous system, its afferent and efferent divisions, how it processes information, the reflex arc, and what your brain has to say about pain.