If the pilot's brain "malfunctioned" , the cause of the crash is pilot error.
That's an oversimplification. Without proper training, spatial disorientation is a real problem. So are knee-jerk reactions like pulling up in a (near) stall condition; most people will "instinctively" react that way, before being properly trained (a fact that many professional pilots may forget, due to their training, but that's how the brain works, initially). Perfectly normal sense can't always be trusted, and there's numerous cognitive biases we need to be aware of and try to mitigate. On top of that, there's the startle effect. Unless you've trained and are prepared for an exact scenario, there's a chance that your brain will be much slower, and it might even do the wrong things altogether. Human brains didn't evolve to fly airplanes, they need to be trained.