Michio Kaku, a theoretical physicist has stated the human brain is the most complex creation in the universe. Indeed the human brain is exceedingly complex, for instance, the total number of synapses in a brain roughly equals the number of stars in 1,500 Milky Way galaxies! or about 250 trillion or 250,000,000,000,000 trillion synapses.
Memory patterns and tiny on/off switches, which were long thought to reside in the larger neuron cell bodies, have instead found to be smaller than the tiny synapse connections. Each of the neurons serves thousands of synapses.
One synapse may contain on the order of 1,000 molecular-scale switches. A single human brain has more switches than all the computers and routers and Internet connections on Earth. Recent research multiplies the brain's overall computing power far beyond what was previously known.
The more complicated a system is, the stronger the argument for having been intentionally designed. And brains certainly qualify, despite assertions that random-acting natural processes somehow assembled them. In these cases, the burden of proof lies heavily on those who insist that such systems are not in fact what they plainly appear to be the products of intentional ingenious design.
The neurons in the brain are incredibly interconnected. Thoughts are originated and transmitted using neurological connections. When you want to perform a brand new action, the brain does its best to use pathways that complete the task efficiently. Repeated practice makes the task easier. Neurons can actually band together and develop brand new connections in order to function more efficiently. After thousands of repetitions, the new pathway becomes so comfortable with the task that it seems automated.
The brain understands the constraints that are put on it. Information travels only as fast as its weakest link, and a person’s brain must live within the ability of the rest of the body. As the body learns to do more, the brain can compensate by making new connections. For example, physical training that increases speed or endurance can place demands on the brain that result in brand new neurological connections.
The billions of neurons and the trillions of neurological connections in the brain enable it to do amazing things. Some people have developed incredible memory, while others have learned to control their muscles with pinpoint accuracy.
The complexity of the human brain in and of itself screams for intelligent design and all the evidence points to an almighty God.