Single neuron binding properties and the magical number 7

Abstract

When we observe a scene, we can almost instantly recognize a familiar object or can quickly distinguish among objects differing by apparently minor details. Individual neurons in the medial temporal lobe of humans have been shown to be crucial for the recognition process, and they are selectively activated by different views of known individuals or objects. However, how single neurons could implement such a sparse and explicit code is unknown and almost impossible to investigate experimentally. Hippocampal CA1 pyramidal neurons could be instrumental in this process. Here, in an extensive series of simulations with realistic morphologies and active properties, we demonstrate how n radial (oblique) dendrites of these neurons may be used to bind n inputs to generate an output signal. The results suggest a possible neural code as the most effective n-ple of dendrites that can be used for short-term memory recollection of persons, objects, or places. Our analysis predicts a straightforward physiological explanation for the observed puzzling limit of about 7 short-term memory items that can be stored by humans.

Differentiation in the arched surface of packaging: Its influence on the findability of logo typography displays

“…Some researchers have therefore proposed that the limited capacity of short-term memory for verbal material is not a ''magic number" but rather a ''magic spell" [37]. Our analysis predicts a straightforward physiological explanation for the observed puzzling limit of about 7 short-term memory items that can be stored by humans [38]. Thus, we accept the result that the memory span is six for letters recorded in literature.…”

Branch-Specific Plasticity Enables Self-Organization of Nonlinear Computation in Single Neurons

“…2006; Larkum and Nevian, 2008;Migliore et al, 2008;Morita, 2008). We show that synaptic clustering is an emergent property of the plasticity mechanisms in our model.…”

Encyclopedic Knowledge Patterns from Wikipedia Links

“…The three small clusters includes seven paths: this feature supports the buzz in cognitive science about a supposed amount of 7 ± 2 objects that are typically manipulated by the cognitive systems of humans in their recognition tasks [11,10]. While the 7 ± 2 conjecture is highly debated, and possibly too generic to be defended, this observation has been used to hypothesize a first threshold criterion: since the seventh rank is at 18.18% in pathP opularity DBpedia , this value of pathP opularity(P i,j , S i ) will be our first guess for including a path in an EKP.…”

“…The resources involved in dbpedia page links en are typed with any of 250 DBPO classes (out of 272). Though, we are interested in direct types 10 of resources in order to avoid redundancies when counting path occurrences. For example, the resource dbpedia:Ludwik Fleck has three types dbpo:Scientist;dbpo:Person;owl:Thing because type assertions in DBpedia are materialized along the hirerachy of DBPO.…”