K. Lashley's Theory of Equipotentiality
The holographic hypothesis grew out of classic experiments by American neuropsychologist K. Lashley. He trained laboratory rats in instrumental defensive tasks and then surgically removed various areas of the cerebral cortex.
The main result of these experiments upended traditional views on memory localization: it turned out that the severity of memory impairment depended exclusively on the volume of damaged brain tissue, rather than on which specific area was destroyed. Based on this, Lashley formulated the principle of equipotentiality. According to this principle, different cortical areas are completely equivalent in terms of storing engrams (memory traces).
Core of K. Pribram's Hypothesis
Building on Lashley's data, K. Pribram proposed a concept explaining the mechanism of such distributed storage. It is based on the analogy of an optical hologram, where any fragment contains the image of the entire object.
Images of past events are reconstructed in consciousness when coherent (mutually consistent) external or internal influences activate their representations in various brain structures. These representations are organized not as single storage cells, but as cellular ensembles with distributed information.
Following the primary recognition of a familiar object, all additional information about it is instantly reproduced because the entire ensemble is activated.
Mechanisms of Formation and Levels of Functioning
Cellular ensembles function by generating slow potentials (postsynaptic and dendritic). Within the physical analogy, these ensembles act as optical wave filters or screens.
Information interacts with these "filters" in a multi-level manner:
- Peripheral receptors — the primary stage of signal reception.
- Subcortical structures — intermediate processing.
- Cerebral cortex — the highest level (with its columnar organization playing a special role).
At each of these levels, correlational interaction occurs between external stimuli and configurations of internal excitation. Incoming information is instantly distributed across all neural tiers. At the molecular level, protein molecules participate in organizing the holographic engram, with resonant frequencies coherent to the stimuli that trigger the memory.
Connection with the Theory of Functional Systems
The holographic principle organically complements the theory of functional systems. Memory does not exist in isolation—it is inherent to every individual element of the dominant functional system. Furthermore, each element reflects the current state of the entire system as a whole during its activity.
Of particular importance is dominant motivation, which acts as the leading component. The mechanism of excitation spread is as follows:
- A pacemaker zone located in the hypothalamus initiates the process.
- Through ascending activating pathways, motivational excitations widely "spread" across numerous brain structures.
- Convergence occurs: neurons united by dominant motivation simultaneously receive excitation from conditioned and reinforcing stimuli, forming a unified holographic pattern.