How Does The Brain Remember?

Stored codes were first discovered by researchers to assist the olfactory system, a functional module, to recognize the smell of an orange. The olfactory module was revealed to use PRCC language to identify the smell, when air borne molecules of octanol enter the nose. Evidently, there are unknown processes, which record PRCC memories into nerve cells. Dendritic firing combinations, which form recognized PRCC inputs, are remembered by nerve cells. These form the massive inherited, or acquired PRCC codes, which carry the declarative, implicit and procedural memories of the brain.

Only PRCC can explain the astonishing brilliance of neural intelligence. Such codes have a virtually infinite capacity for storing and recalling microscopic pattern recognition details. Intelligent actions are only possible through a massive interchange of infinitely precise data between numerous functional neural modules. The screen images of a man and that of a mouse are instantly differentiated visually through a mere rearrangements of combinatorial pixel patterns. PRCC implies that a neuron fires, when it recognizes a combinatorial pattern in the array of its receiving dendrites. The pattern may be a single signal in the array, signals in a channel in the array, or a specific combinatorial pattern of signals in the array.

PRCC was discovered to be applied for hundreds of millions of years by the olfactory sense for the instant identification of odors. This website suggests that implicit memory for an odor is assembled, when nerve cells routinely record the related firing combinations. Such memories, which subsequently cause the cell to fire, may be further consolidated through LTP, neural plasticity, or neuronal reverberation.

How Does The Brain Remember – Implicit & Declarative Memories
All nerve cells recognize patterns using PRCC memories. Science defines declarative memories as those, which act to produce conscious events. Such awareness involves neural interactions with RI in the prefrontal regions. All other activities of the brain occur in its subconscious regions, utilizing implicit memories. An implicit memory may help an amnesic patient to guess which of two faces he saw most recently, while his impaired declarative memory may make him assert that he has not seen those faces at all.

When RI receives PRCC signals from other active regions of the brain, it becomes aware of an event. The following paths and processes can explain how space/time and emotion references can assist the brain to recall memories. PRCC signals require parallel projections. Science reports that visual images travel in parallel projections from your eyes to be mapped exactly as seen, in your visual cortex. Visual images are also known to be received and recalled from the same regions of the visual cortex. It is suggested that such images are recorded against space/time/emotion PRCC signals. The hippocampus is known to assist in the recording of the space/time context of “interesting” events. Emotions are known to be signaled by nuclei from the limbic system.

Messages from the hippocampus, or strong emotion signals record the images of the 9/11 falling towers into the receiving visual cells. When the 9/11 emotion/space/time PRCC signals are encountered again by the system, the original visual cells, which recorded the event, fire again. The PRCC image signals reach RI in the prefrontal regions. On receiving those impulses, RI recalls the image. The images enter conscious awareness, implying a declarative memory.

How Does The Brain Remember - Recognition of Combinations
A Nobel Prize was awarded in 2004 for the discovery that the olfactory network recognizes combinations. On this basis, a neuron with 100 dendrites can recognize 1, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000 unique combinations!

The human visual system has not 100, but millions of individual pixels, which can represent an infinity of combinations! Combinatorial recognition enables the kind of ability, which enables people to remember and recognize any one of 10,000 images, shown to them at one second intervals. That is how the brain does remember.

How Does The Brain Remember - The Relevance of Parallel Projections
Parallel projections enable nerve cells to transmit combinations. Throughout their growth, the axons of nerve cells extend and map on to specific target regions in parallel projections. Consider the messages carried by a bundle of glass fibers. If each fiber carries an individual message, the relative location of the fibers will be irrelevant. But suppose each fiber carries one pixel of a black and white picture. In this case, if the relative positions of the fibers change between the sending and receiving ends, the black and white picture will be lost. If the objective is to transmit a combinatorial picture, the fibers have to be projected in parallel.

Each area of the somato-sensory cortex is proportionally linked to the number of nerve endings in the corresponding part of the body. Touch sensory cells in your fingertip have identical proximity relationships when they finally report touch to the cortex. Similar parallel projections exist in numerous other regions. Such mapping implies a combinatorial purpose in the nervous system. The brain does remember combinations.

How Does The Brain Remember - Pixel Specific Barrels
Visual receptors send signals of each pixel of light to cells in the visual cortex. Each pixel is recorded by a vertical barrel of thousands of nerve cells within a diameter of 200 to 500 microns, extending through all layers of the cortex. Each barrel is linked by a single axon which transmits that pixel to the cortex. Thousands of neurons in it act together, with connected timings, when a stimulus is received from its receptor field. These vertical barrels represent pixel specific information, which is further interpreted by other regions of the cortex.

The visual system has dedicated functional groups of over 30 processing centers, which categorize, the color, texture, outlines and edges. Any image finally received by RI is a sophisticated interpretation, which fills in gaps and identifies an object. A rabbit behind a picket fence is not seen as the slices of a rabbit, but as a whole animal. When a complex pattern of related barrels fire, you will recall the image and know it is a rabbit.

How Does The Brain Remember – A Space/Time/Emotions Broadcast
The vertical barrels in the cortex have both radial and parallel fibers. Radiating downwards from the cortex are millions of fibers which directly link the Barrels through the thalamus to all sensory and motor functions. This link is called the "specific link". The cortex also had a surface layer which runs a thick network of fibers parallel to the surface. These fibers are also linked to the thalamus.

The link was recognized when it was discovered that stimulation of the "non-specific nuclei" of the thalamus led to wide-spread "recruiting activity" in the outer layers of the cortex. Emotion signals from the limbic system and the space/time relationship signals recorded by the hippocampus are broadcast in the outer layers, accessing every barrel in the cortex. Those barrels, which recognize a specific contextual signal, fire to recall an image. That is how the brain does remember.

At any moment in time, your mind is dominated by a single group of emotions. An intuitive decision making process selects the current emotion. Since the current emotion is broadcast in the outer layers of the cortex, the emotion affects your recalled memories and motor responses. The relationship of emotions to the patterns of recalled data is pivotal. If you are angry, you remember the wrongs committed by your opponent. If you are fearful, you remember the previous instances, where you failed. Your motor responses also respond to your emotion. Your emotions grant you a partisan view of life. When they are quieted, your RI has a global view and your actions have a calm wisdom.

How Does The Brain Remember - The Hippocampus
The hippocampus provides strong space/time book marks for the memories of significant experiences of the mind in the sensory and recognition regions of the cortex. During REM sleep, the hippocampus replays the context of significant waking experiences. LTP circuits within the organ increase synaptic strength for such links. Neuronal reverberation, where linked nerve cells fire in rhythm, record PRCC in all the linked groups of cells. Over many sleep/wake cycles, the organ spreads associative learning to extensive regions of the nervous system. During sleep, the thalamo-cortical link enables the hippocampus to dispatch PRCC signals, which reinforce emotion memories in the vertical barrels of the cortex during sleep. Subsequently, the emotions are recognized by the barrels, which fire to recall sensory memories. That is how the brain does remember.

Researchers at MIT trained rats to run along a circular track for a food reward. Their brain activity was monitored during the task and during sleep. While the animal ran, its brain created a distinctive pattern of neurons firing in the hippocampus. The researchers then examined more than 40 REM episodes recorded while the rats slept. About half repeated the unique signature of brain activity that was created as the animal ran. The correlation was so close that the researchers found that as the animal dreamed, they could reconstruct where it would be in the maze if it were awake and whether the animal was dreaming of running or standing still.

With damage to the hippocampus, the nervous system loses its ability to bookmark, store and consolidate its episodic memories. Nature has provided a mechanism to replay the space/time context through rapid eye movements during sleep, causing persistent neuronal reverberation in the cortex, hippocampus, putamen, and thalamus. Incremental learning continues several nights after memory acquisition due to the progressive recruitment of larger neuronal networks over time. The hippocampus also has mechanisms, which progressively disengage the organ from its older memory consolidation processes. Such memories, can recall events in the space/time/emotion context after months and years.

How Does The Brain Remember - Place Cells
In the vast database of the mind, memories require reference links to enable their recall. The nervous system constantly monitors its current location. The hippocampus uses eye movement and head direction data as an inertial compass to chart geographic movement and position. Visual and sound information triangulate the location. These eye and ear coordinates are mapped by head direction cells, grid cells, and border cells in the entorhinal cortex and the closely linked hippocampus. These regions were discovered to contain a neural map of the spatial environment in rats. The firing cells in the arrays lack any spatial topography in the representation. Cells lying next to each may have uncorrelated spatial firing patterns.

The place fields record the place looked at by an animal in four dimensions, including time. In humans, the cells even indicate one's position in virtual reality spaces. The time dimensioned PRCC signals by the place cells in the hippocampus trace the directions, objectives and movements of an individual in his environment. Such memories may be both for events and experiences as well as for semantic concepts (ideas converted into words and sentences). Damage to the hippocampus causes a loss of this key reference point for episodic memories.

How Does The Brain Remember – Event Memories
Edvard Moser reported, in 2011, that memories are stored in different regions of the brain and that a consolidated memory develops in about 125 milliseconds. He monitored different parts of a rat's brain as it explored its neighborhood. Different lighting schemes in a single box tricked the rat into believing it was in different neighborhoods. Distinctly different memory locations became activated in the rat's brain in each visualized location.

The rat instantly adjusted to a new environment indicated by a different lighting scheme by recalling a different memory from a different part of the brain. Moser discovered that each memory was an integral whole for the 125 millisecond period. When the environment changed, the brain of the rat switched the memory to recollect details of a new background. There was no confusion between the memory location barrels in the rat's brain, when the changed environment was “completely different.”

How Does The Brain Remember - LTP
Combinatorial memories are supported by additional processes. Long term potentiation (LTP) enables neurons to become sensitive to a single contextual signal. A neuron may also grow new dendrites (neural plasticity), increasing accessibility to active communication channels. Procedural memory is saved when linked neurons fire repetitively during physical practice of the procedure. Declarative memories for complex events are assembled through neuronal reverberations, where groups of linked nerve cells fire in rhythm.

The Npas4 gene may play a role in the recording of such PRCC memories. Researchers at MIT discovered that by knocking out the Npas4 gene in the DNA in the hippocampus, they created mice which kept entering cage compartments, in spite of continued foot shocks. They had interfered with the sequence of processes, which recorded memories of those painful experiences. The motor memories, which enabled the animal to run, remained.

How Does The Brain Remember - Neuronal Reverberation
The tactile, gustatory, olfactory, spatial, and motor activities produced by the free exploration of novel objects trigger precise contextual PRCC links in multiple brain structures. When these active groups of neurons fire in rhythm, among millions of silent ones, they store PRCC memories. Ann Graybiel recorded this process in the basal ganglia of a monkey, while it learned to associate the sound of a click with the availability of a sip of juice. Neuronal reverberation, when connected groups of neurons fired rhythmically, converted the action into a remembered drive for the animal. After learning, the task did not require conscious effort for the animal.

Representations in working memory decay unless they are refreshed. Attention to a task increases neural activity in all contextual regions of the nervous system, which are involved in execution of the task. If the mind is engaged elsewhere, the task is less well remembered. The attention load depends on the speed of the processing task. Adding digits every half second places a higher load on the system than when adding them every two seconds. The working memory does not require any inputs other than attention.

After a novel experience, demanding attention from an animal in a cage, the correlation of neuronal reverberation between groups of cells increases dramatically. This process repeats for several hours after the learning experience. At the same, firing patterns related to experiences with less new information (movements along the bare sides of the cage) reduce. Cortical recognition identifies a new geographic feature as being relevant to the goal of learning. Attention to the feature intensifies the activity in the nerve cells, which perceive and recognize. They fire in rhythm, triggering the acquisition of PRCC memories. Sustained experience-dependent neuronal reverberation can be detected in several cortical areas up to 48 hours after exposure to novel experiences.

How Does The Brain Remember – Repetition Registers PRCC
Procedural memories assist a person to play a musical instrument, or to ride a bike. Procedural memories, which directly empower the motor system in real time, are acquired through practice. Repetitive activity records the PRCC memories in nerve cells. Such memories cannot be consciously recalled, but are available as a remembered ability.