Archive for March, 2014

The Impact of Sleep on Memory

by Dr. Stacy Loyd, HCA Academic Dean

Sleep: We fight it as small children, and bemoan the lack of it as adults.  We all know that we need to be getting more than we do, but why exactly is it so important?

God created every living creature to need sleep. Sleep is especially important for children as it directly impacts mental and physical development. Sleep is considered to be important to body restitution, like energy conservation, thermoregulation, and tissue recovery (Maquet, 2001). In addition, sleep is essential for cognitive performance, especially memory consolidation (Maquet, 2001; Stickgold, 2005; Alhola, P & Polo-Kantola, P, 2007).  God designed sleep to trigger changes in the brain that help improve memory.  “New memories are formed in the working memory when a person engages with information to be learned. However, these memories are initially quite vulnerable; in order to ‘stick’ they must be solidified and improved. This process of ‘memory consolidation’ occurs when connections between brain cells as well as between different brain regions are strengthened, and for many years was believed to develop merely as a passage of time. More recently, however, it has been demonstrated that time spent asleep also plays a key role in preserving memory” (Science Daily, June 29, 2005).

“Working memory can be divided into four subsystems: phonological loop, visuospatial sketchpad, episodic buffer and central executive (Baddeley & Hitch, 1974; Baddeley 2000). The phonological loop is assumed to temporarily store verbal and acoustic information (echo memory); the sketchpad, to hold visuspatial information (iconic memory), and the episodic buffer to integrate information from several different sources. The central executive controls them all. Executive processes of working memory play a role in certain attentional functions, such as sustained attention (Baddeley et al 1999), which is referred to as vigilance. Both attention and working memory are linked to the functioning of frontal lobes (Naghavi & Nyberg, 2005). Since the frontal brain areas are vulnerable to sleep deprivation (Harrison et al 2000; Thomas et al 2000), it can be hypothesized that both attention and working memory are impaired during prolonged wakefulness” (Alhola, P & Polo-Kantola, P, 2007).

The need for enough rest is paramount throughout our lives, from children to adulthood.  So what can you do to ensure that your child is getting enough sleep?

Four Tips to Ensure Good Sleep:

1. Know how much sleep your child should be getting.  Visit the Sleep Foundation website for a handy chart.

2. Maintain a regular routine.  Children thrive on consitency, and this helps set their body clock to a regular rhythm.

3. Keep bedtime early, especially if your child is behind on sleep.  Going to bed extra early for a few days in a row can help them catch up on lost hours.

4.  Create a bedtime routine.  This gives children signals that let them know it’s time to sleep.


Leave a comment

Undauntedly Pursuing God Through His Creation

by Christine Humphrey, HCA Secondary Science Teacher

One of the common organizing themes for science, particularly life science, is to start with the microscopic and move to the macroscopic. In both regular and AP Biology, we recently finished studying cellular structure, in all its microscopic glory.

As we began the unit, I thought of how much the cell and its micro-machines (organelles) manifests God’s glory. Tiny rotors whirl and create usable energy.  Small motor units are attached to larger structures, moving them across a complex of scaffolding and tram lines that would make a city planner proud.  Shuttles shepherd special molecules to just the right place and keep processes humming along.  The encompassing membrane filters what can get in and out of the cell and has the ability to even rearrange itself in response to changes in its environment. Wouldn’t you like your car coolant to be able to self-regulate in response to changing temperatures? Is there damage to some part? No worries, a special structure can degrade the used out, worn out part and recycle its components (um – yes please, I’d like a car that can do that!).  The more advanced technology has become, the more the microscopic world cries out that there is a Designer extraordinaire.

As I was pondering the cell at the start of our unit, it reminded me of a deeper truth from scripture.  Each magnificent part in a cell has a role and purpose it is designed to fulfill.  Granted, some molecules can serve multiple roles, but many of the larger systems are specialized and they exist to serve a major overarching function.  In the same vein, Paul talks about our role as believers in the body of Christ.

In I Corinthians 12:12-27 (excerpted), he states:

“The body is a unit, though it is made up of many parts, and though all its parts are many, they form one body…If the foot should say ‘Because I am not a hand, I do not belong to the body,’ it would not for that reason cease to be part of the body…If the whole body were an eye, where would the sense of hearing be?  If the whole body were an ear, where would the sense of smell be?  But in fact God has arranged the parts in the body, every one of them, just as He wanted them to be…”

In other words, in God’s economy, every one of us has a purpose and our function, whatever God has designed us to do, is necessary to others.  It doesn’t matter whether I am old or young, rich or poor, well known, or not so well known, athletic or not, “popular” or not, and… my list could go on.  What truly matters is that I am doing what God has designed me to do. Just as the cell’s very existence depends upon each part fulfilling its function, so too in the Body of Christ.

Secondly, pondering cells reminds me of just how creative God is.  In just the human body, there are numerous types of cells, cells (and beyond them the tissues, organs and organ systems they make up) specialized for conduction, excretion, movement of substance, transmission of impulses, cognition, response, etc. In the same way, God has imbued humanity with numerous personalities that reflect Him. Now I recognize that even as believers we have a fallen nature, but I was challenged to think a little differently about personality in the 1st chapter of A.W. Tozer’s The Pursuit of God.

Tozer states:

“All social intercourse between human beings is a response of personality to personality, grading upward from the most casual brush between man and man to the fullest, most intimate communion of which the human soul is capable.  Religion, so far as it is genuine, is in essence the response of created personalities to the Creating personality, God.”

When I became a mom, I realized just how myopic my view of personality was.  You see, God gave me a son who was very different than I.  As a teacher, I had recognized and valued differences in students, but somehow when it was my son, I behaved in a fashion that shouted “you need to be more like me!”, or, “I’m an epidermal cell you need to be one too; I’m a foot, you need to be one too.” And I am still a work in progress on this point.  As I read Tozer’s words several weeks ago, it made me want to consciously look at personalities different than myself for the “Creating personality”.  Tozer continues:

“God is a Person…In making Himself known to us He stays by the familiar pattern of personality.  He communicates with us through the avenues of our minds, our wills and our emotions.  The continuous and unembarrassed interchange of love and thought between God and the soul of the redeemed man is the throbbing heart of the New Testament religion.”

And so I close. In the microscopic world of the cell, systems carry out their pre-designed function. In our macroscopic world, may we as well. For God’s creativity in making us (whatever we are in the Christian body – a foot, a hand, a toenail) and fashioning our personality, is part of His story and exists to glorify Him to the world at large.


Leave a comment

%d bloggers like this: