the Human Brain from 1 to 86 billions

1 – Apart from some obvious exceptions, the average person has one brain. It’s located inside the skull and represents the center of the nervous system. The brain exerts a centralized control over the other organs of the body. Brain death is the irreversible end of brain activity; it is used as a legal indicator of death in many jurisdictions.

2 – The human brain has two hemispheres that function differently. This means that each hemisphere, left or right, controls different functions. Language, math and logic are mainly controlled by the left hemisphere, while creativity, spatial abilities, visual imagery and music depend on the right one. A funny thing is that the right side of the brain controls muscles on the left side of the body, and vice versa. Therefore, damage to one side of the brain will affect the opposite side of the body.

3 – Three pounds is the average weight of the human brain. Switching to more common units, we have about 1.3 kg of mass in about 1130 cubic centimetres (cm3, or cc). Take the quantity of water contained in one bottle of 1 liter plus one coffee cup and you’ll have the same volume.

4 – Each cerebral hemisphere is divided into four lobes. Their identification is made by considering sulci and gyri, respectively the grooves and the bumps that can be seen on the brain surface. The Frontal Lobe is located in front of the central sulcus and is concerned with reasoning, planning, parts of speech and movement (motor cortex), emotions, and problem-solving. Behind the central sulcus there is the Parietal Lobe, that treates the perception of stimuli such as touch, pressure, temperature and pain. Below the lateral fissure we have the Temporal Lobe, devoted to perception and recognition of auditory stimuli (hearing) and memory (hippocampus). At the back of the brain, behind the parietal and temporal lobes, there is the Occipital Lobe, mainly concerned with many aspects of vision.

5 – Somebody started arguing that the human brain makes us see ourselves five times more beautiful than we actually are. If you accidentally read that somewhere, it’s junk science. This is not scientific at all, but it may be interesting to have a look at this video.

6 – The first six months of life are really important for brain development. During the first six months of life, babies gradually gain information about the world around them. After depending mainly on their caregivers, babies grow and develop faster in the first year than any other year. There is a host of techniques to boost babies’ cognitive development during their first 3-6 months of life (an example here), mainly by reading and talking to them, making them interact with toys and people, proposing them different situations in order to enhance their senses, and so on.

7 – seven items is the typical capacity of the so-called “brain’s working memory”. As explained on this website, countless psychological experiments have shown that, on average, the longest sequence a normal person can recall on the fly contains about seven items. Typical scenarios: recalling a phone number, or the items from a mental grocery list (that’s why we write it down!), or all the names of the seven dwarfs (one of the hardest things in life…). Comparing the human brain to a computer, the working memory is somehow the RAM, while the long-term memory is the hard drive. The complex brain activity imposes the limit of seven items to the working memory, which provides continuity from one thought to the next and allows quick conversations and computations. The very complex biochemical machine we have inside our head continuously manages a stunning number of interneuronal communications, at each time instant. Mathematical models can estimate the huge network of firing neurons, thus estimating the working memory’s capacity… that is, on average, only seven items!

Unfortunately, we don’t have time (and space), here, to get to 86 billions, that is the number of neurons in the human brain (according to the latest plausible estimate). One billion is 10⁹, or 1 000 000 000, or a thousand millions (10³×10⁶). And yes, we have 86 times this quantity of neurons in our three pound magic box!

other source: this amazing website