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.
Improving selective attention – potential therapeutic targets
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
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