9 unanswered questions about the human brain
Much has been revealed about the inner workings of the human brain, but many mysteries remain unsolved. Dr Rebecca Tan looks at some neuro puzzlers
The average human brain has about 90 billion neurons that make 100 trillion connections or synapses. Scientists believe this staggering number of neurons is responsible for the traits that make us uniquely human: our thoughts, memories and emotions.
Recent technological advances in functional magnetic resonance imaging, optogenetics and whole-brain imaging have made the brain accessible in ways that previous generations of neuroscientists could only dream of. Yet, many pieces are still missing from the puzzle. Here are nine unsolved questions in neuroscience.
1. How is information encoded by neurons?
The brain has often been likened to a computer. In essence, both follow the same basic principles: electrical inputs arrive in the brain, which are then processed before leaving as electrical outputs. While computers encode information in a binary fashion, much less is known about how neurons encode information. What we do know is that neurons conduct electrical impulses down specialised extensions known as axons, before releasing chemical signals to neighbouring neurons at junctions called synapses. These electrical and chemical signals carry information about everything we see, hear, taste and touch.
