Attention

Attention is one of the most important aspects of cognition. . Stronger or more foucsed attention is positively correlated with control over anxiety and performance in intellectual tasks. In this section, we will introduce two systems that define the brain’s attention mechanisms: the Central Executive Pathway (CEN) and the Default Mode Network (DMN).

The Default Mode Network (DMN) is a group of brain regions that are active when we are daydreaming, recalling memories, envisioning the future, monitoring the environment, or thinking about the intentions of others. In the language of activation of neural circutry, , the Default Mode Network shows high activity when we are not engaged in cognitively demanding tasks, a state that might be defined as “at rest” or “in reflection”. This initially was discovered because scientists noticed that patients had high neuronal activity between tasks when they were supposed to be at rest. In terms of attention, this network is activated when our attention isn’t fixated on any particular stimuli.

The CEN is a group of brain regions that are active when we are focused on a task: playing guitar, playing chess, doing homework, driving etc. Part of the network is associated with starting or stopping a task, and another part of the network is associated with the process of executing the task itself.

It is important to note that both of these are large-scale brain networks, so the activation of DMN or CEN involves not just a few brain structures, but the entire brain firing with specific pathways.

The DMN and CEN have an inverse relationship. When CEN is activated, the DMN is inhibited, and when the DMN is activated, the CEN is inhibited. This makes sense because when we are focused on a task with our full attention, our mind does not have the freedom to wander into past and future scenarios.

Activities such as meditation decrease the intensity of DMN activation and improves overall focus because it strengthens the pathways that activate the CEN without needing a fight or flight stimulus to do so. Everytime you meditate, you activate the CEN pathway. From our section on memory, we know that LTP (long-term potentiation) rates increase as a group of neurons fire more. LTP causes changes in the concentration of various proteins, such as neurotransmitter receptors, on the dendrite of a neuron that allow it to reach action potential easier. In other words, the more a neural pathway is activated, the easier it is to activate (reach action potential) in the future. Meditating essentially is a ‘work-out’ for the CEN neural pathways, and eventually leads to one being able to activate their CEN with ease since these neurons now reach action potential far easier than they could before.

Now, let’s talk about the neurological pathway that initializes our attention to focus on a stimulus . First of all, attention is first and foremost a biological hardwiring that allows us to determine if a sound or sight is dangerous and warrants the fight or flight response. When we first encounter a stimulus, the information goes from our sensory organs to the brainstem, specifically the Locus Correales. Following its activation by a stimulus, the Locus Correales releases norepinephrine into the bloodstream, which is the ‘fight or flight’ hormone. The locus correales takes this sensory information and feeds it to the orienting system near the cerebellum, which tells your body where the stimulus is coming from in space in relation to you. Now comes the part with the CEN and DMN.

If you have strong neural connections in the CEN, your frontal lobes will be activated after a stimulus and you can assess how dangerous the stimuli is in a calm manner. If it is not perceived as a threat, the activation of your CEN will slow non-epinephrine production and your amygdala will not be fed a fear response. You will fall out of ‘fight or flight’ mode quickly.

If you have strong DMN neural connections, your frontal lobes will not be activated after this stimulus and you lose your ability to rationalize the level of the threat. Even if you consciously realize that the current stimulus should not invoke anxiety, your brain is used to being in DMN mode so you will still not be able to properly assess the threat physiologically. Norepinephrine production won’t be inhibited and the amygdala will be activated, resulting in fear response.

With an overactive DMN, trivial stimuli will have the tendency to trigger a fight or flight response. With a more active CEN, you will be able to focus on your current task and not allow other stimuli to affect you as an active CEN trains your brain to be less reactive to everyday stimuli.

(Do we want to keep this section here?) Now, I will talk about how improvements in the technology sector are being used to treat attention deficit diseases, such as ADHD. On a neurological level, a person with ADHD is known to have higher gray matter content for DMN regions, and as such their DMN activates easily.

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0216225#sec028

In this article, there was an 8 week program using simple BCI technology designed to see if children with ADHD would find improvements in attention. Each participant would wear a BCI headband that could read dry EEG signals. This BCI contains a machine learning model that can take the brain’s EEG signals and give a numerical rating for attention levels based on the EEG. The BCI has been trained with lots of data to generally know what EEG looks like for a highly attentive state and what EEG looks like for a highly non-attentive state. Using machine learning, the BCI is able to specifically gather data for individual brains and adjust its rating system accordingly. This is important because everyone’s brain chemistry is a little different, so you always want to gather neurological data from the unique patient you are treating.

The BCI is hooked up to a 3D racing videogame via bluetooth, and the game receives EEG data. The higher a participants attention score (based on EEG reading), the faster your character in the videogame goes. The lower a participants attention score (based on EEG reading), the slower the character goes. It’s really cool because there are certain checkpoints in the game that don’t allow you to move on unless your attention levels reach the threshold. After 8 weeks of this training, the treatment group saw significant improvements, while the control group kept going to regular school. The treatment group saw significant improvements in attention levels and cognitive scores (they aren’t more intelligent now, but they merely put more energy and focus onto multiple cognitive tasks). The control group was then put into the treatment and they saw significant improvements.

This technology is really cool because it’s an interactive and super safe therapy for children with ADHD. Since most kids are addicted to video games anyways, this is a great idea because it ties attention training into an activity many kids are already addicted to.

On a neurological level, what is happening is these kids are training their CEN. When they reach max speed in the racing video game, it means they are at ‘max focus’. By constantly using this CEN neural pathway, these kids are inducing LTP along this pathway, thus strengthening the community of neurons involved in attention. This means these neurons can reach action potential easier