A Dark Space

“Alright, Hank?” 
“Alright as ever, Jim. All I can say, is thank goodness it’s Friday.”
“Teeell me about it. My back is sore from yesterday’s dig. And staying past 5:00 PM to blow open that channel? Do they think we’re paid by the hour or somethin’?”
“Whooee! You’re tellin’ me! Oh well. Today’s case is a good one. This lady has 89 life years. I love these types of brains. Goodness knows that most of them synapses will have been pruned away by this point, so our path should be nice and clear. Whaddya say we take a slow day today, and make some stops to watch some of them memories along the way?”
Hank and Jim were memory miners, employed as part of a big data governmental initiative that sought to characterize the internal structure and storage patterns of the human brain at different life stages. The two were especially small, which allowed them the ability to pass between cells and skull layers, rappelling into brains. For these two, weekdays involved taking field notes while burrowing through sulci, climbing gyri, and sliding down axons (with the occasional wellness break thrown in). 
“You speak my language, Hank. Let’s start at the rear then and make our way forward?”
And so they went. Hank and Jim entered through the occipital lobe, and it was not long before they got distracted.
“Gee. Come take a look at this memory, Jim. It’s completely blocked. I would bet any money that this is a dementia case. Would you come and help me dig it out?”
“Ah sure. Why the heck not. I hope not too many of them memories are lost to her though, or it sure is gonna be a long day.”
Hank pulled a well-worn shovel out of his pack, and began to chip away at the massive mound of fatty tissue that was obscuring the memory from view. 
“Aint it funny, Jim? All of this modern day technology, mapping brains and the like, yet we here are still using old-fashioned shovels. Sometimes there's just no substitute for brute force, wouldn’t ya say?”
“I sure would, Hank!”
Jim, who had been sticking his foot between two tightly packed brain folds, yanked it out suddenly, and stumbled over to where Hank dug with clumsy enthusiasm. With the two working together, the tissue soon became transparent enough for the memory to be appreciated. 
“Wow! This must be one of the first things she ever done saw. Who do you think that man is? It must be her dad. And he is giving her a box. Oh, ain’t that nice. Is it...shaking? Hank, I’m scared!”
Jim clung onto Hank’s arm with such fervour that his fingernails began to make indentations in the heavy canvas that was Hank’s sleeve.
“What in the name?”
“Sorry Hank, I just wasn’t expecting a cat to jump on right out of that box! Ain’t that the sweetest thing though? And they’re hugging.”
“Personally, I’m more of a dog kind of guy. And not those little pocket dogs either. I like real dogs. The kind that protect your family.”
“Is that a tear coming from his eye? I love that. It’s such a shame that she don’t remember that no more.”
Motivated after uncovering a viable memory so early in their day, Hank and Jim carried on with uncharacteristic vigour toward the left temporal lobe, where memory was stored as audio clips.
“Jim, at this rate, I think we can get out of here before the department store closes up shop. I told my wife I would get her up a pair of them fuzzy slippers today. Alright, put them earplugs in there, Jim. The memories here tend to come up quickly.”
SCREEEEEEECH
“What was that?”
“WHAT?”
“What was that?”
“I can’t hear you, Jim! That pitch done made me near deaf! Speak up, son!”
“Oh gee. I think we found ourselves another memory, and this one don’t sound so good. Sometimes, I think I am just too squeamish for this kind of work, Hank. I shouldn’t have listened to Pa. He always wanted me to be practical. I could be a real famous actor today, you know that?”
“Quit your babbling, Jim. Give me a listen.”
The two listened in silence to the distinct sounds of two cars colliding, accompanied by shrieks, and exclamations as a father was lost and a daughter survived.
“Wow. That’s rough.”
“Yeah.”
“Hank, I’m not liking these memories so much no more.”
“I know, Jim. Let’s just finish excavating this lobe, and then we can move on up to the front.”
“Okay. I’m glad you’re here, Hank. We make a good team.”
Click, click, click…reeeneeeeeeeeiiiigh
“Ah, Hank! I found one right on over here. It’s horse sounds!” 
“Oh yes. Good find, Jim. This memory seems well-preserved too. Since we don’t have to dig this one out, why don’t we take our lunches and give it a listen?”
The pair removed their ear plugs, and sat down to eat their lunches on a particularly squishy myelin sheath. As they listened to the memory, they gathered that following the passing of her father, the girl whose brain they now occupied had been taken in by an aunt who resided in the country. Though still distraught and lonely, she was able to fill the void at least in part by caring for a large work horse, named Dungaree.
“Well, there’s no way around it, it sure is sad when a kid loses them parents too young, but at least there was still some happiness.”
“Yeah. It’s true. Alright, I guess we should get a move on. Shall we head on up to the prefrontal cortex?”
Jim and Hank made their way to their final destination of the work day – the notoriously complex prefrontal cortex. 
“Oh darn. Look at this one, Hank. It is blocked to the roof!”
“I told you it was dementia. This will take a lot of work to access. We really should not have taken such a long lunch break.”
“Ack. You’re right. Maybe we should use the dynamite for this one, if we want any chance of making it out of here by 5:00. My back is still too sore for digging anywho.”
“Alright. Let’s do it.”
The dynamite excavation revealed an empty space with a large multi-sensory memory vibrating at the center. After a long, uncomfortable pause, Hank cleared his throat and spoke first.
“...Well, what are ya waitin’ for, Jim? Go on and open it up now.”
“Uh, yeah. Sure thing, Hank.”
Jim and Hank tenderly approached the pulsating memory with pliers of a sort, meant to unfold complex materials. Prodding it caused a rebound effect, thrusting them backward. What they saw next was a flurry of memories that seemed to move in and out of focus. The first memory was filled with uncertainty. The two miners saw life from the perspective of the young girl, as she peered up nervously toward her aunt’s new boyfriend. He gave her a toothy grin, and tugged on her pigtail, telling her that she was a very pretty young lady. This was soon followed by uncomfortable hugs and unwelcomed bathroom visits, with the man explaining all the time that they were family now. Finally, Hank grabbed Jim’s shoulder, and Jim covered his eyes in distress. They watched as the man made loud casual conversation, for the ears of anybody who might be near enough to hear, as he pinned down the slight girl, and shielded her mouth. Her eyes ballooned with terror as he forced his hand up her dress. The memory halted abruptly, and the two miners were left in a dark space.
“…Hank? Where do we go from here?”
“I really don’t know, Jim.”
For the excavation had left a wall barring the path that had led the two to this point, and all that remained was darkness.

Author’s note:
Depression is the most common treatable illness seen in the elderly1. Due to its relationship to dementia, which has yet to be fully understood2,3, depression in older adults is often missed and perceived by caretakers as being a by-product of cognitive impairment, rather than an independent illness4. Although the processes of long-term memory storage are still being characterized, some believe based on the work of Lashley5 that memories are not encoded and stored in one specific region of the brain, but rather, that they span the entire brain, with particular aspects of memories being localized in the neurons that fired to create the original experience. More recent theorists have provided evidence to support a theory that recent long-term memories are stored in the hippocampus, while as memories age, they move toward the prefrontal cortex6.
References
[1] Saikia, A. M., Mahanta, N., Saikia, A. M., Deka, H., Boruah, B., & Mahanta, R. 2016. Depression in elderly: a community-based study from Assam. Indian Journal of Basic and Applied Medical Research; 5(4):42-48.
[2] Heser, K., Bleckwenn, M., Wiese, B., et al. 2016. Late-Life Depressive Symptoms and Lifetime History of Major Depression: Cognitive Deficits are Largely Due to Incipient Dementia rather than Depression. Journal of Alzheimer’s Disease; 54;185-199.
[3] Wang, C., Gao, S., Hendrie, H. C., Kesterson, J., Campbell, N. L., Shekhar, A., & Callahan, C. M. 2017. Antidepressant use in the elderly is associated with an increased risk of dementia. Alzheimer Disease & Associated Disorders; 30(2):99-104.
[4] Wang, S., & Blazer, D. G. 2015. Depression and Cognition in the Elderly. Annual Reviews of Clinical Psychology; 11:331-60.
[5] Lashley, K. 1950. In search of the engram. Society of Experimental Biology Symposium; 4:452-482.W
[6] Costandi, M. (2009, February 10). Where Are Old Memories Stored in the Brain? Retrieved from https://www.scientificamerican.com/article/the-memory-trace/

- Nicole Krysa