Interference
Interference is the process of overwriting old memories with new memories (retroactive interference). It occurs in neural networks. Interference will also cause difficulty in forming new memories when the stability of old memories is high (proactive interference). Interference is the prime cause of forgetting, and explains its exponential nature. One of the chief problems of schooling is excess volume and excess speed that result in a leaky vessel approach to learning: new knowledge easily displaces old knowledge in a process that results in minimal learning. Reducing interference may be an important component of building memory stability as predicted by the Neurostatistical Model of Memory.
It is important to differentiate between two forms of interference:
- interference between memories
- interference between memory signals registered at a single synapse
The above differentiation is important because interfering memories may target and strengthen or weaken the same synapse. At the same time, competing signals may send contradictory information to the same synapse. Non-interfering memories may compete at the level of a synapse. The latter case may result in random forgetting of seemingly unassociated information.
The implication for education is that free learning maximizes coherence while using interference as a tool of generalization. In contrast, in coercive teaching, interference is a dominant force that prevents formation of stable, and coherent memories.
See also: Coherence vs interference problem of teaching
This glossary entry is used to explain "I would never send my kids to school" (2017-2024) by Piotr Wozniak
Figure: Uncertain course of the stabilization of complex memories. The picture shows a hypothetical course of stabilization, forgetting, generalization, and interference on the example of a single dendritic input pattern of a single concept cell. The neuron, dendrites and dendritic filipodia are shown in orange. The picture does not show the conversion of filopodia into dendritic spines whose morphology changes over time with stabilization. The squares represent synapses involved in the recognition of the input pattern. Each square shows the status of the synapse in terms of the two component model of long-term memory. The intensity of red represents retrievability. The size of the blue area represents stability. After memorizing a complex memory pattern, the concept cell is able to recognize the pattern upon receiving a summation of signals from the red squares representing a new memory of high retrievability and very low stability. Each time the cell is re-activated, active inputs will undergo stabilization, which is represented by the increase in the blue area in the input square. Each time a signal does not arrive at an input while the concept cell is active, its stability will drop (generalization). Each time a source axon is active and the target neuron fails to fire, the stability will drop as well (competitive interference). Due to the uneven input of signal patterns to the concept cell, some synapses will be stabilized, while others will be lost. Forgetting occurs when a synapse loses its stability and its retrievability and when the relevant dendritic spine is retracted. Generalization occurs when the same concept cell can be re-activated using a smaller, but a more stable input pattern. Retroactive interference occurs when a new input pattern contributes to forgetting some of the redundant inputs necessary for the recognition of the old input pattern. Stabilization of the old patterns results in the reduced mobility of filopodia, which prevents the takeover of a concept by new patterns (proactive interference). At the every end of the process, a stable and a well-generalized input pattern is necessary and sufficient to activate the concept cell. The same cell can respond to different patterns as long as they are consistently stabilized. In spaced repetition, poor choice of knowledge representation will lead to poor reproducibility of the activation pattern, unequal stabilization of synapses, and forgetting. Forgetting of an item will occur when the input pattern is unable to activate sufficiently many synapses and thus unable to reactivate the concept cell. At repetition, depending on the context and the train of thought, an item may be retrieved or forgotten. The outcome of the repetition is uncertain