Biology Online is a Biology blog and dictionary site that provides up to date articles on the latest developments in biological science. The Biology Online Dictionary is a completely free and open dictionary with over 60,000 biology terms. It uses the wiki concept, so that anyone can make a contribution.
Tag: neurobiology

Brief Diversions Help Keep Selective Attention in Top-notch

The ability to focus one’s attention on a specific point of interest for a given time is referred to as selective attention. Imagine a scenario wherein you can pay attention to everything. That would lead to information overload. Selective attention enables an individual to react to certain stimuli from among those occurring simultaneously. This ability is crucial particularly when you need to focus on a task you need to finish before the time is up. You tend to put much of your attention to your target and then ignore potential distractions.

 

 

 

Neurobiology of selective attention

Selective attention is one of the neural functions of the brain. The neurons relay the information from one neuron to the next by releasing neurotransmitters, such as acetylcholine, at the synapse. The neurons responsible for our capacity to focus are found in the lateral prefrontal cortex.1 They are also responsible for suppressing potential distractions in the background. For more neurobiological aspect and potential therapeutic targets, read Selective Attention – neurobiology and potential therapeutics.

 

 

 

Selective attention and inattentional blindness

While we can choose which of the things to focus on and which ones to ignore, there are also instances wherein we tend to overlook things beyond our will. One of the possible consequences of selective attention is inattentional blindness, which is the phenomenon of not being able to perceive things although they are just right in front of our eyes. Because we are focused on one thing, there is a tendency that other things escape us. For instance, you might not notice the tiniest details on your essay (e.g. misspelled words) or missed key information from a reference book.

Inattentional blindness can be perfectly demonstrated through Daniel Simons and Christopher Chabris’ invisible gorilla test. The test is a video of two basketball teams in which the viewer has to count how many times the ball is tossed around to the team members. The viewer would likely be so busy counting that the person in a gorilla suit walking back and forth on the background would easily go unnoticed. Because of selective attention, we are inclined to filter things out. We might even think that we saw everything but, in fact, we only see what we want to see. Thus, letting other salient details to slip out while on selective attention is not unusual.

 

 

 

Brief diversions improve selective attention

Imposing short and momentary breaks helps to rest mentally from sustained stimulations, and thereby, possibly keep up excellent selective attention.

One could easily surmise that selective attention and distractions should never go together when one wants to complete a highly demanding task. However, this seems to be the opposite based on what Atsunori Ariga and Alejandro Lleras from University of Illinois at Urbana-Champaign found in their study.2 Repetitive tasks that required prolonged selective attention could wind up to diminished quality in performance. The researchers presumed that diminishing attention per se was not the culprit to a poor performance but the constant stimulation happening in the brain. Lleras explained: “Constant stimulation is registered by our brains as unimportant, to the point that the brain erases it from our awareness.” What their study implicates is to impose short and momentary breaks to rest mentally from sustained stimulations. Brief breaks, as they proposed, will help to stay focused while doing long, arduous tasks, such as studying before an exam.2

 

 

 

Perhaps, we can all agree that there are times when selective attention can be a cinch and then there are also times when it is simply impossible. We can get easily distracted. There are just so many factors that prevent us from focusing on a daunting task. An emotional turmoil, for instance, is one such distraction that can be difficult to overcome. Nevertheless, these studies open up to possibilities how diversions and distractions can be put to use to uphold selective attention to tasks that need to be done over prolonged periods of time.

 

 

 

— written by Maria Victoria Gonzaga

 

 

 

References:
1 McGill University. (2015, January 7). Having a hard time focusing? Research identifies complex of neurons crucial to controlling attention. ScienceDaily. Retrieved from www.sciencedaily.com/releases/2015/01/150107081701.htm
2 University of Illinois at Urbana-Champaign. (2011, February 8). Brief diversions vastly improve focus, researchers find. ScienceDaily. Retrieved June 5, 2018, from www.sciencedaily.com/releases/2011/02/110208131529.htm

Selective Attention – neurobiology and potential therapeutics

Selective attention refers to the ability of an individual to focus. We can choose what to pay attention to and then ignore all else unless it is something worthy of our attention. Think about this: a day before the final submission of an essay project, you would probably be pressured into doing nothing else but to read and write to finish the task as soon as possible. You would probably clear yourself off from all the conceivable distractions like a favorite TV series or a video game. You might even go as far as going to a place secluded, away from all irrelevant noise and people just so you could focus and finish it on time. Yes! That is basically how selective attention works.

 

 

 

Selective attention – the neural basis

So how about the neural basis of selective attention? Our brain is made up of two major types of cells: neurons and glial cells. The glial cells mainly are for supportive functions whereas the neurons play a part in cell-to-cell communication, particularly for conducting nerve impulses. The information is relayed from one neuron to another, much like a text message relayed through an instant messaging app from the sender to the recipient. In this regard, the acetylcholine takes the role of the app that relays the nerve impulse (the message) from one neuron to the next. Besides acetylcholine, other brain chemical systems may also be at work for selective attention to ensue. A research on the attention mechanisms in a primate model revealed that glutamate coupled to NMDA receptors was found to be involved as well. 1 Thus, in order to elicit focus and attention, the message has to be essentially loud and clear.

Neurotransmitters are released from a presynaptic neuron (A), exerting effects on post synaptic neuron (B).
(Credit: WikiMedia Commons, CC BY-SA 3.0 Unported license)

 

 

 

Improving selective attention – potential therapeutic targets

Selective attention refers to the ability of an individual to focus. We can choose what to pay attention to and then ignore everything else unless it is something worthy of our attention.

 

Our ability to focus and, at the same time, suppress distraction lies on the neurons located in the lateral prefrontal cortex of our brain.2 The neurons in this brain region do not only serve as the selective attention machinery but also as the anti-distraction system.3 This means that while they enable us to pay attention to important matters they also suppress distractions in the background. This could serve as a potential therapeutic target for producing a drug that could help improve selective attention.

 

In another research, a team of scientists identified three structures, namely cortex, thalamus, and thalamic reticular nucleus (or TRN, a thin layer of neuronal cells surrounding the thalamus.), that apparently formed neuronal circuits in mouse brain models.4 These neuronal circuits seemed to control the selective attention and sensory processing in the animal’s brain. In essence, the sensory information initially passes through the thalamus where it is determined as to whether relevant or not. It, then, has to pass through the TRN before it can reach the cortex for processing. When they inactivated the ErbB4 protein in the TRN, they found that the selective attention of the mice amid distractions was greatly affected. This could, therefore, be another therapeutic aspect to consider.

 

 

 

Attention Deficit Disorder (ADD) – impaired selective attention

Attention deficit disorder or ADD is a neurologic disorder associated with impaired selective attention. An individual with ADD is struggling to focus and easily gets distracted. As a result, completing salient tasks can be a challenge because the attention is easily diverted to other stimuli that are irrelevant to the initial task. ADD may or may not involve hyperactivity. The condition in which the person experiences not only an impaired selective attention but also manifests excessive activity and behavioral problems inappropriate for one’s age is referred to as attention deficit hyperactivity disorder or ADHD. People with ADD without hyperactivity may not necessarily show behavioral problems. Nonetheless, their attention shifts to other extraneous activities resulting in slow-paced, poor performance.

 

A deeper understanding on the neurobiological basis of selective attention is essential because they could serve as potential therapeutic targets. Individuals with attention deficit disorder are just one of those who might benefit. Without focus, we would hardly be able to keep up with the simple chores to the more challenging undertakings. A functional selective attention does have a crucial role in enabling us to complete a task in time.

 

 

 

— written by Maria Victoria Gonzaga

 

 

 

 

References:
1 Herrero, J.L., Gieselmann, M.A., Sanayei, M., &Thiele, A. (2013). Neuron. 78(4):729-39. doi: 10.1016/j.neuron.2013.03.029. https://www.cell.com/neuron/fulltext/S0896-6273(13)00276-6
2 McGill University. (2015, January 7). Having a hard time focusing? Research identifies complex of neurons crucial to controlling attention. ScienceDaily. Retrieved from www.sciencedaily.com/releases/2015/01/150107081701.htm
3 Gaspar , J., McDonald, J., & Thorbes, C. (2014). Scientists discover brain’s anti-distraction system. Simon Fraser University Media Release. Retrieved from http://www.sfu.ca/university-communications/media-releases/2014/scientists-discover-brains-anti-distraction-system.html
4 Cold Spring Harbor Laboratory. (2014, December 15). Neuronal circuits filter out distractions in brain. ScienceDaily. Retrieved June 4, 2018 from www.sciencedaily.com/releases/2014/12/141215114240.htm