@jeeprs,
I can, actually, understand your wondering, there, jeeprs, in that I know that most folks, on most internet forums, don't take the time, effort, and conscientiousness to give a fuller, and detailed background and underpinnings to their arguments. Not to deride that, no . . . simply to point to such circumstance, and that then looking from that circumstance, see why you would wonder what I am doing here; with all this detail. I am presenting the background for the 'case-in-point's which come up later, which, in turn, will be used in developing the argument, namely:
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KaseiJin;93258 wrote:
With the title, I am presenting the process of approaching the theme, along with the correlation of the three things--brain, consciousness, and mind--and their foundational situational basis, namely that of biological concern. . . At the same time, we will be able to explore the depth and nature of correlation between brain and mind, and by extension the foundational, biological basis of mind and consciousness. . . In this manner, I argue the position that mind, and consciousness are robustly involved with, and foundationally determined by, brain, and that thus it is more accurate and especially fair enough to contend that they are foundationally biological concerns.
[/indent][/indent] which argument will be to demonstrate areas where certain philosophical positions need either rethinking or refining--as well as (along the way), perhaps, areas where findings/understandings in the brain sciences stand rethinking or refining. There is a good chance, you see, jeeprs, that somewhere down the road, someone'll come up and ask, "How do we know that?" Well, as much as possible, I wish to demonstrate firstly, rather than then (and mid-argumentation), how we know that.
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W[/SIZE]hile the cerebellum has direct connections to the spinal chord, the basal ganglia do not, but interact with the cerebral cortex.
The general flow of information runs from the cerebral cortex to the striatum where it synapses with projections to various areas of globus pallidus, ventral tegmental area, substantia nigra (pars compacta & reticulata), and the sub thalamic nucleus.
The general outflow (after all inner flows) is to areas of the frontal lobe. The cerebellum could be said to be more directly active in regulation and planning (based on memory search) of (especially) ballistic movement, whereas the basal ganglia participate in what could be called the cognitive dimensions of movement--thus the structures dual role of is planning and execution of motor strategies.
The skeletomotor loop more specifically
recieves input from the primary motor, lateral premotor, supplimentary motor areas, and primary somatic sensory areas into the putamen which synapse with globus pallidus internal and substantia nigra pars reticulata where
output goes to the ventral anterior & lateral thalamic nuclei.
From there, feedback/output flows to the motor areas. One interesting aspect is the higher working load degree of the basal ganglia is by inhibitory, rather than excitatory activities--
and some of the excitation is actually caused by disinhibition (inhibition of inhibitory spiking). The direct path of the skeletomotor loop promotes movement, and the indirect path inhibits movement.
The neurotransmitters and neuromodulators involved are (among a few possible others)
glutamate (excitatory; corticostriatal neurons input into basal ganglia, thalamic neurons projecting to the striatum, and the subthalamic projection neurons),
GABA (inhibitory; the medium spiny projection neurons of the striatum feeding both segments of the globus pallidus & the substantia nigra pars reticulata, and projection neurons of both segments of the globus pallidus and substantia nigra pars reticulata),
enkephalin (a peptide contained largely in the medium spiny neurons),
substance P (a peptide also contained largely in the medium spiny neurons),
dynorphin (an endogenous opiod),
dopamine (catecholamine) contain by neurons in the substantia nigra pars compacta & the ventral tegmental area), land
acetylcholine (in the striatal interneurons).
This is the normal build, and in looking at this overall motor system, we can see that we have very complicated circuitry, and that the interaction (internal feedback) makes a difference in the system's 'self-control' (so to speak) as does input (feed forward and feed back) from outside the system as well (such as emotional, visual and auditory input). This motor system working normally, as it normally does,
(1) is how the muscles work to move (thus body movement). Body movement is not always a matter of acknowledgement (or awareness) at the consciousness level--
and in cases, even the urge to move (although the movement itself is acknowledged in consciousness, having moved). Body movement is not always volitional in nature either (not talking about pure reflexes here). It is most clear, however, that brain controls body movement.
1. While there is a spectrum of build, in very minute detail from one H. sapien brain to another, there is still the 'normal' range within the bell curve.