“Cartesian theater” is a derisive term coined by scientist Daniel Dennett to refer pointedly to a defining aspect of what he calls Cartesian materialism.
Descartes originally claimed that consciousness requires an immaterial soul, which interacts with the body via the pineal gland of the brain. Dennett says that, when the dualism is removed, what remains of Descartes’ original model amounts to imagining a tiny theater in the brain where a homunculus (small person), now physical, performs the task of observing all the sensory data projected on a screen at a particular instant, making the decisions and sending out commands (cf. the homunculus argument).
The term Cartesian Theater was brought up in the context of the multiple drafts model that Dennett posits in Consciousness Explained (1991):
Cartesian materialism is the view that there is a crucial finish line or boundary somewhere in the brain, marking a place where the order of arrival equals the order of “presentation” in experience because what happens there is what you are conscious of. Continue reading
The homunculus is commonly used today in scientific disciplines such as psychology as a teaching or memory tool to describe the distorted scale model of a human drawn or sculpted to reflect the relative space human body parts occupy on the somatosensory cortex (the “sensory homunculus”) and the motor cortex (the “motor homunculus”). Both the motor and sensory homonculi usually appear as small men superimposed over the top of precentral or postcentral gyri for motor and sensory cortices respectively.
The homunculus is oriented with feet medial and shoulders lateral on top of both the precentral and the postcentral gyrus (for both motor and sensory). The man’s head is depicted upside down in relation to the rest of the body such that the forehead is closest to the shoulders. The lips, hands, feet and sex Continue reading
The neocortex (Latin for “new bark” or “new rind”), also called the neopallium (“new mantle”) and isocortex (“equal rind”), is a part of the mammalian brain. In humans it is the largest part of the cerebral cortex which covers the two cerebral hemispheres, with the allocortex making up the rest. The neocortex is made up of six layers, labelled from the outer in, I to VI.
In humans, the neocortex is involved in higher functions such as sensory perception, generation of motor commands, spatial reasoning, conscious thought and language. There are two types of cortex in the neocortex – the true isocortex and the proisocortex.
The neocortex is the most developed of the cerebral tissues. The neocortex consists of the grey matter, Continue reading
From The Thinking Business
It was the ancient Egyptians who first noticed that the left brain tends to control the right side of the body and the right brain tends to control the left side of the body. Although each hemisphere is almost identical in terms of structure, each hemisphere operates in an entirely different way and are associated with very different activities. This is known as specialization or lateralization.
The left brain is the logical brain responsible for words, logic, numbers, analysis, lists, linearity and sequence. It controls the right side of your body.
The right brain is the creative brain and is responsible for rhythm, spatial awareness, colour, imagination, daydreaming, holistic awareness and dimension. It controls the left side of your body. Continue reading