The Missing Black Box
Since we will be looking at consciousness on Wednesday and again on Saturday 28th, it seems an opportune moment to bring this older post up to the front again : How are brain and consciousness connected? Did you know that our brains have actually shrunk in size over the last 100 000 years ? What exactly is the relationship between mind and brain ?
The two event next week will focus more on consciousness – what is it and how can it be investigated ? So here is some background to set the picture:
The brain is a loose term for the Central Nervous System which runs from the underneath of the skull to half way down the back. It comprises neurons, and glial cells which provide nutriments and clean up waste. There are literally billions of neurons, each with sometimes 10 000+ connections to other neurons. All of this is enclosed in a tight skin that acts as a blood filter, keeping only highly refined blood inside, and the coarser blood for the body out. This sack of neural matter connects out to the body by an upper set of nerves called cranial nerves, and a lower set call spinal nerves. These spread throughout the body sensing, or stimulating muscles. The longest such nerve is the sciatica which reaches from the back down to the toes.
Gram for gram, the brain sucks up far more blood sugar even than the heart. Daily energy consumed is roughly equivalent to 250 M&Ms.
A neuron is remarkably simple. It only does one thing – if it receives pulses from other neurons in its ‘tail’ with enough rapidity, it will fire a pulse through its ‘head’ to other neurons. There is only one kind of pulse of a single length and voltage. No variety.
So neurons only real function is to connect to other neurons. There is the additional issue of the synaptic gap – a tiny gap between the head of one neuron and the tail of its neighbours. A variety of neurochemicals make this gap either more or less likely to pass any signal on. Basically this is it – neurons are wires that connect to other wires. Neurons don’t actually ‘do’ anything, other than pass a received pulse on to other neurons until that pulse is fed out through the cranial or spinal nerves of course, and then the signals can activate all kinds of organs and muscles. The neo cortex, the outer cauliflower part we all recognise, seems to cover conscious activity, while the deeper parts going all the way down into the spine, seem to govern unconscious operations such as breathing, temperature etc..
The God of Gaps
In the late 1600s an Englishman called Robert Hooke used the newly invented compound magnifying glass (2 lenses together) to look for the first time directly at the living cell. He and others thought the cell would be the building block of matter. Now we know of course that cells are highly complex biological organisms with many constituents – and these constituents can be broken down all the way to atoms and possibly quarks. The point is that even when the cell was discovered there remained a ‘black box’ – they still did not know how the cell workrd.
Such a ‘black box’ is often called ‘God of the Gaps’ since Creationists like to claim that the holes in our knowledge of things, allow for the intervention of God. That is, anything that can’t be explained, is attributed to God.
But we have a problem with the neuron. We have seen it in its entirety. There are no more hidden corners of the neuron for which we are waiting for the next generation microscope to see. It has been exposed down to its atoms, and we know every single thing that it can do. Yet we have no idea how consciousness works. We have no idea how thoughts or memory work. We have no idea how images, sensory feelings, or speech centres work.
Take for example the ‘areas’ of the brain ‘responsible’ for function x, y or z. These areas vary in location person to person. Further, if damaged the function can be shifted to other areas. For example, the speech centre – Wernick’s area – where speech is ‘generated’. If you pull out some of the neurons from this area they are indistinguishable from any other neurons, such as those from the motor cortex (cerebellum excluded). All neurons do is connect to other neurons. This is why we get such fuzzy descriptions such as ‘the area of the brain connected with function x’. We have no idea what is going on, and worse, there is no black box left to be opened.
One thing is fairly clear. To fathom the way the brain works science will have to get away from a mechanistic materialist view. We have seen how the parts work and it does not add up to any kind of explanation. Does this leave the door open for the God of the Gaps after all ?
It would be foolish to look to scriptures for a scientific explanation of things, especially something so complex as the brain. But we do have a few hints and tips. According to Buddhism, memory can survive the death of the body, and continue into a future life. Mind is something that can be sent out of the body with psychic powers. This does not mean that it can be separated from the body exactly, but it does mean that its function is not purely material functioning in a mechanical way. If this is accepted as a possibility there will be room for more collaboration. In the mean time, one of the Dalai Lama’s comments, which should seem obvious on an empirical basis, has been gaining ground. He suggested that it is not the firing of the neurons that creates thought, but that it is thought that fires the neurons.