“The different parts of the neocortex, whether they are responsible for vision, hearing, touch, or language, all work on the same principles. The key to understanding the neocortex is understanding these common principles”
Sensory Functions: everything that we do is carried out by the brain, from the most simple reflex acts, like hitting a tennis ball, running, or riding a bicycle, to the most creative aspects. (Rose, Episode 1 Eric Kandel) We can make a distinction between (the brain functions of) “sensation” and “perception.” Sensation is the registration of physical “stimuli” from the “environment” by the sensory organs, whereas perception is the interpretation of sensations by the brain. (Kolb, 269) (Neurocommunication) in the brain depends on the ability of nerve cells to respond to very small stimuli. “Receptors” in the eye respond to a single “photon” of light; “olfactory” neurons detect a single molecule of odorant; and hair cells in the inner ear respond to tiny movements of atomic dimensions. These sensory responses ultimately lead to the firing of an “action potential” (Kandle3, 100) Genetic Instructions play only a minor role in the detailed assembly of cortical connections. With twenty thousand genes and 200 trillion connections between neurons, how could the details possibly be prespecified? Instead, neuronal networks require interaction with the world for their proper development. (Eagleman, 21) Your senses do provide the information you need to act, but they don’t present your brain with an objective reality. Instead, they give your brain the information it needs to construct reality. (Kandel4, 8)
Feedback: the coupling of the “output” of a process to the “input.” Feedback mechanisms are important in regulating many physiological processes; for example “hormones” and “neurotransmitters.” (OxfordMed) A mechanism of communication within a system in that the input signal generates an output response which returns to influence the continued activity or productivity of that system. (MeSH)
Feedback Loop: the visual, auditory, somatosensory, "reticular activating," "limbic" and frontal lobe systems are interconnected in a positive continually recurring feedback loop that takes a stimulus from the outside world, extracts its salient features and then bounces it from region to region, before eventually figuring out what it is and how to respond to it. (Ramachandran, 116) The massive 'feed forward' and feedback projections are in the business of conducting successive iterations that enable us to home in on the closest approximation to the truth. (Ramachandran, 112)
Reverberating Loops: recurrent bioelectrical activity. Associated with “re-entry.” (Goldberg, 112)
Servo-Control Loop: real-time, feedback-driven mechanism such as that which occurs in the “cerebellum.” (Ramachandran, 18)
Polysensory: the opposite of localization. Brain’s sensory areas are able to process signals from more than one sense. (Doidge, 17)
Redundancy: a built-in characteristic of brain (pathways). Many sensory, motor, and cognitive functions are served by more than one neural pathway - the same information is processed simultaneously and in parallel in different regions of the brain. (Kandel, 124)
Sensation: of, or pertaining to, the senses. Transmitted by the senses. (Oxford) Processes that involve and promote the transfer or transmission of sensory information from the periphery to more central organized structures and mechanisms involved in processing information. (NCIt) The detection and basic sensory experience of environmental stimuli, such as sounds, objects, and odors. The process of detecting a physical stimulus. (Hockenbury, 85) Characterization created by the brain by combining information from all “sensory receptors.” For example, wetness, hairiness, fleshiness, rubberiness. (Blakeslee, 9) Also referred to as ‘sensory.’
Senses: the faculties by which the qualities of the external environment are appreciated. (OxfordMed)
Sensorium: the world as experienced through the senses. (Blakeslee, 20)
Sensory Information: environmental stimulus such as touch, pain, or light (Kandel, 79) Tactile (sense of touch) inputs are delivered to the “somatosensory cortex.” Auditory inputs are delivered to the “auditory cortex.” Visual inputs are delivered to the “visual cortex.” (Hawkins, 114) Inputs are just patterns that arrive in a sequence. (Hawkins, 127) In the attainment of understanding, incoming sensory information is usually not enough to lead to an unambiguous interpretation. In such cases, the cortical networks 'fill-in.' They make their best guess, given the incomplete information. This ‘filling-in’ happens throughout the body. The principle “jumping to conclusions” actually guides much of human behavior. (Koch, 23) Also referred to as 'sensory input,' ‘sensory data,’ and ‘sensory stimuli.'
Intensity: the degree or magnitude of strength, energy, or feeling. (NCIt) The measure of a sensory input—whether a touch is gentle (brush on the skin) or heavy (bumping an elbow), whether a light is bright or dim. The intensity of a stimulus results from the "frequency" with which “signals” are emitted. (Kandel, 77-78)
Temporal Processing: determining how long things (events) go on, how long they last. (Doidge, 73) The duration of a sensation is determined by the length of time over which the signals are generated. (Kandel, 78)
Sensory Reception: translation (of) different kinds of information from the external world into electrical patterns that are sent down our neurons. (Doidge, 18)
System: a complex (pathway) that performs some specific function, like seeing or hearing, or detecting and responding to danger. A series of hierarchically arranged (pathways) linked together by synaptic connections. (LeDoux, 49) Also referred to as ‘circuit system.’