When you decide to either do something or not according to your perception of situations in which you try to evaluate all possibilities, your brain uses, basically, a map created by your senses. And, complicated actions is due to the evaluation of the situations perceived by your brain.
When you perceive the objects around you, your senses creates a template of this object for you to comprehend these objects in a very intertwined mechanism. Without this mechanism, you cannot act as what you please and consider your actions effects on the environment. The reason is as follows. The concept of being able to have a copy – or template – of real objects as regards your senses is an increasingly important concept in brain sciences, and it is called the efference copy. The word efference here means the same thing as output, or action(1). Furthermore, which is why you compensate when you perceive a change in the objects, through your senses, even if there is no movement, such as shifting your gaze or hearing in a different direction. In other words, when an object does move in the environment, you register it and act if it is needed. In that regard, with an efference copy mechanism, as you decide to act, you command your body to make a change in your position as compared to the previous one as regards the discrepancy between efference copies. And also, because of it, you have a palpable feeling when you affect the environment with your actions because efference copies tell the brain, “Here is how things should look, given what I just did(2).” In its very core, you perform complicated actions in your life due to efference copies created by the brain.
Even though this article focuses on the human brain and efference copies, all living things which have the ability to perceive the changes in the environment through an efference copy mechanism, such as animals, perform complicated actions rudimentarily.
(1) Godfrey-Smith, Peter. "Our Minds and Others." Other Minds: The Octopus and The Evolution of Intelligent Life. London: William Collins, 2018. 144. Print.
(2) Godfrey-Smith, Peter. "Our Minds and Others." Other Minds: The Octopus and The Evolution of Intelligent Life. London: William Collins, 2018. 145. Print.
Figure - 23.1 https://www.vox.com/science-and-health/2016/12/29/13967966/machine-learning-neuroscience
Figure - 23.2 http://www.isciencemag.co.uk/wp-content/uploads/2015/03/decision-making-nerovivo-1403329318_1024w.jpg
Figure - 23.3 http://www.enzolifesciences.com/science-center/technotes/2016/august/updated-map-of-the-human-brain/
Figure - 23.4 http://www.jneurosci.org/content/33/41/16110
Figure - 23.5 http://www.endurance-education.com/home/aragorn/www/endurance/htdocs/wp-content/uploads/Bagnall-McLean-2012-Fig-1.png