Experimental data show that beyond synapses the molecular structure distributed within neurons is directly involved in learning, computation and storing memories http://neuroelectrodynamics.blogspot.com/p/spike-directivity.html (Aur et al.,2005; Aur and Jog,2006; Hameroff et al., 2002; Woolf et al., 2009). Understanding the puzzle of mind and cognition in computational terms has to reveal at least three major aspects:
(i) Where are our memories stored?
(ii) How are memories ‘read’ or ‘written’ ?
(iii) How is information continuously integrated in the brain?
Where are our memories stored?
The semantic knowledge gradually accumulates from childhood to adulthood. Always personal experiences can add new semantic content which has to be systematically kept in the brain. In addition to synapses the entire cell function is involved in storing memories.
(i) These fragments of information are stored inside neurons within macromolecular structures in proteins (Hameroff et al., 2002; Woolf et al., 2009, see regions in cyan color)
(ii) A continuous reorganization of internal neuronal structure occurs in time
(iii) Subtle changes in the structure of protein molecules can change how this information is distributed inside the cells or between different neurons
(iii)
(iv) Consequence: This phenomenon of continuous reorganization generates experimental issues since it may provide changes in electrophysiological recordings.
What does DNA stand for?
Therefore the internal structure inside the cell is not randomly built. Within their three-dimensional structures all molecular formations (proteins) embed specific spatial charge distributions.
(i) The selection of genes (Comoletti et al., 2006) represents an important factor in shaping structure-dependent charge density
(ii) Refining the macromolecular structures (charge density) is a continuous process that leads to new protein synthesis regulated by gene expression
(iii) This reorganization of information inside the neuron can be reshaped by repetitive strong interaction that occur during spiking activity . New information electrically brought in continuously accumulates while ‘old’ already stored information has to be restructured under the influence of biochemical and electrical factors
Example: With learning an increase of organization occurs inside specific cells ( e.g expert neurons - Aur and Jog, 2007, Aur and Jog, 2010; Aur, 2010).
Therefore, in order to accumulate new information the organization of macromolecular structure within cells increases from childhood to adulthood while the strength of neural activity diminishes toward adulthood.
Example: Correlated with this phenomenon, the maximum synaptic density (absolute number of synapses per neuron) is reached by age 1 year and strongly decreases during the preschool years (Huttenlocher, 1984; Bastrikova et al., 2008)
Therefore:
(i) Internal reorganization of information storage inside cells provides less redundant storage of fragments of information distributed within various cells
(ii) The entire process of synapse elimination leads to a more efficient access to information stored in neurons
(iii) Efficiency principle: The same neurons can be involved in different cognitive processes, different fragments of information can be ‘read’ from molecular structure just by changing the spatial propagation of APs (see spike directivity) http://neuroelectrodynamics.blogspot.com/p/spike-directivity.html
(iv) The reorganization of information within cells significantly alters neuronal response (temporal patterns)
(v) These changes in neuronal molecular structure and synapses generate in time different more efficient brain rhythms from childhood development to adulthood (e.g. temporal patterns).
(vi) The structure of matter inside neurons and its organization is controlled by specific regulatory mechanisms required to preserve information and provide fast access
(vii) The entire process of reorganization follows the efficiency principle (principle of optimality, NED)
(viii) An increased organization determines efficient responses (less spikes) and less energy required to complete various tasks
(ix) The generation of order in intracellular structure reflects the ‘memory storage’
(x) Consequence: The mind can be remodeled by reshaping the biological substrate within neurons
Therefore, the entire architecture underlying memory formation is far more complex depends on inherited traits and occurs all the way from protein expression to transcription of the DNA sequence of the gene. In addition to synaptic changes the genetic component is subtlety involved in building molecular blocks within neurons underlying distinct intracellular signaling.
Example: Significant differences between animal and human levels of cognition are genetically encoded in DNA segments
How are memories ‘read’ or ‘written’ ?
The neurons accumulate fragments of information within their molecular structure (proteins). This information is transferred to electrical flow in the brain during spiking activities (APs, synaptic activities) and such processes allow a direct retrieval of semantic information in the brain.
Therefore, electrical propagation within and between neurons is not a simple process of conduction, it provides access to information intracellularly stored in various spatial locations (dendrites, axonal terminals)
(i) The existent structural order in molecular formations within neurons represents the ‘memory’ that can be read during the transitory spiking periods.
(ii) The process of interaction during spike propagation (APs, synaptic activity) is the moment when information stored within molecular structure is ‘read’ or ‘written’.
(iii) Specific rhythms are required to read or write information.
Example: The phases of sleep have an important role in generating critical electrical rhythms required to provide a selection of genes involved in new protein synthesis (Stickgold, 2007), a process of building memory by ‘writing’ fragments of information within new molecular structures.
(iV) In addition, severe alterations of brain rhythms are associated to many neurological disorders and reflect abnormal changes in neuronal molecular structure which may indicate dysfunctions in the life cycle of proteins http://neuroelectrodynamics.blogspot.com/p/from-spike-timing-dogma-to.html(Aur, 2011)
How is information integrated?
From childhood to adulthood the brain forms and maintains an internal model of the external world, the world is in your head (Lehar, 2002). The subjective image of the 'world' is structured in time within neurons by accumulating information.
Example: The 'body image' is part of the subjective 'world' structured inside neurons (e.g Penfield's homunculus). Local electrical stimulation (electrical interaction) reveals the representation of body parts (Penfield and Boldrey, 1937).
Fragments of semantic and non-semantic knowledge are assembled together during spike generation creating the whole from parts. Since in the brain optimal computation is semantically oriented, meaning can be directly obtained through interactions within selected neurons that fire APs (Aur and Jog, 2007, Aur and Jog , 2010).
The meaning of the whole created in the brain becomes a function of the meaning of the parts ‘read’ from many neurons (fragments of information) through electrical interactions mediated by many other factors (e.g. neurotransmitters). The electric flow of information provides the ‘active memory’.
Example: The 'body image' is part of the subjective 'world' structured inside neurons (e.g Penfield's homunculus). Local electrical stimulation (electrical interaction) reveals the representation of body parts (Penfield and Boldrey, 1937).
Fragments of semantic and non-semantic knowledge are assembled together during spike generation creating the whole from parts. Since in the brain optimal computation is semantically oriented, meaning can be directly obtained through interactions within selected neurons that fire APs (Aur and Jog, 2007, Aur and Jog , 2010).
The meaning of the whole created in the brain becomes a function of the meaning of the parts ‘read’ from many neurons (fragments of information) through electrical interactions mediated by many other factors (e.g. neurotransmitters). The electric flow of information provides the ‘active memory’.
Direct consequences:
(i) Since fragments of information are distributed in many neurons then several cells have to fire together in order to integrate information and retrieve the semantic content
(ii) Therefore, sustained interaction within neurons and between neurons is required to generate active memory (the working memory hypothesis)
(iii) The incoming input (sensorial or not) is transformed based on existent stored information since the subjective 'world' is already in your head;
(iv) During 'working memory activation' the entire process of interaction generates well known changes in brain rhythms
(v) This process explains the millisecond precision of firing or the presence of synchronous activity during sustained attention or higher-order language skill
Within neurons the electrodynamics of AP propagation yields meaningful submillisecond spatial kinetics (Aur et al., 2005; Aur and Jog, 2007; Aur and Jog, 2010; Aur, 2010). Therefore, the geometric interpretation towards understanding brain function (Linas, 2008) has to start with a variable spatial dynamics within neurons on a submillisecond scale that directly provides the relationship from the molecular to the cognitive level. This ‘dynamic’ geometry reflects internal interactions critically important to access fragments of information stored inside neurons. These interactions have to be extended in large brain areas to electrically integrate information in a timely- spatially organized manner to generate consciousness.
From matter to thought and back
From matter to thought and back
Neuroscience and neural computation have perpetuated the gimmick of spike timing and reductionist models that have lead nowhere in understanding the neural code or cognition (Aur and Jog, 2010, Aur, 2011;Poznanski, 2002). The dynamic reorganization of information stored within molecular structures embed semantic and non-semantic knowledge. These fragments of information are continuously inferred through interaction during spiking activities. The incoming input is transformed based on existent stored information and the entire process relates the subject to outside world events.(see computation by interaction http://neuroelectrodynamics.blogspot.com/p/computing-by-interaction.html) .
The interaction between the electric flow ( e.g. Na+, K+, Cl-, Ca2+) and structured, organized matter within neurons (Friesner, 2005) provides the transition from structured matter to thought and generates a cohesive explanation regarding memory and cognition.
Importantly, in addition to genetic factors, the power of thoughts can influence brain rhythms and therefore subtlety, slightly change in time the structure inside the cells. The entire process represents the hinted action of mind over matter.
References:
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Steven M. Lehar, 2002, The World in Your Head: A Gestalt View of the Mechanism of Conscious Experience, Lawrence Erlbaum Associates
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