Programmed from birth

Are we born with the knowledge of how to behave or react to our surroundings It might seem ridiculous that we are programmed to react a particular way at birth, but we know that for some behaviours this is true. We will see later that it is possible that it is true for most behaviours, even though we may not realize it. For new-borns, reflexes lead the way for their first reactions to the environment. Newly hatched birds open their mouths to feed, new-born foals stand and run and new-born human...

Average brain weights

Marine Mammals. Evolutionary Biology. San Diego Academic Press Blinkov, S.M. and Glezer, I.I. 1968. The Human Brain in Figures and Tables A Quantitative Handbook. New York Plenum Press Demski, L.S. and Northcutt, R.G. 1996. The brain and cranial nerves of the white shark an evolutionary perspective in Great White Sharks. The Biology of Carcharodon carchar as. San Diego Academic Press Mink, J.W.,Blumenschine, R.J. and Adams, D.B. 1981. Ratio of central nervous...

Finding our way through the white and the grey

Motor Strip The Frontal Lobe

If you examine a man having a gaping wound in his head, reaching the bone, smashing his skull and breaking open the viscera of his skull, you should feel palpate his wound. You find that smash which is in his skull like the corrugations which appear on molten copper in the crucible, and something therein throbs and flutters under your fingers like the weak place in the crown of the head of a child when it has not become whole. Anonymous (c.1550 bce), in Ebers papyrus (cited in J. F. Nunn,...

Temporal lobe epilepsy emotions from nowhere

Epilepsy is a spontaneous electrical discharge that can start anywhere in the brain. Because of this, it is useful for natural experiments. Asking people with epilepsy to report their experiences during an attack and recording the electrical disturbance itself allow us to discover how each part of the brain produces our experience of the world. From such studies, we have learnt that damage to the limbic system can cause laughing and crying. A particular form of epilepsy, in which the electrical...

The brain as a computer

Because we do not understand the brain very well we are constantly tempted to use the latest technology as a model for trying to understand it. In my childhood we were always assured that the brain was a telephone switchboard. (What else could it be ) I was amused to see that Sherrington, the great British neuroscientist, thought that the brain worked like a telegraph system. Freud often compared the brain to hydraulic and electro-magnetic systems. Leibniz compared it to a mill, and I am told...

Closing the pain gate

In the spinal cord, where the pain nerves connect with other nerves, is the pain gate. Nerves dealing with touch sensation can switch off the connections between a pain nerve and the rest of the chain, which means that a pain signal arriving in the spinal cord cannot go any further and the pain sensation never arrives in the brain. We have all experienced the pain gate in action by rubbing it better. This contact with a painful area activates the touch nerves that block the pain nerves. This...