Number of synapses in cortex

Value 3.6e+14 Unitless Range: 29,800 synapses/neuron Unitless
Organism Human Homo sapiens
Reference Roth G, Dicke U. Evolution of the brain and intelligence. Trends Cogn Sci. 2005 May9(5):250-7. p.253 right column 1st paragraphPubMed ID15866152
Primary Source Rockland KS. Non-uniformity of extrinsic connections and columnar organization. J Neurocytol. 2002 Mar-Jun31(3-5):247-53.PubMed ID12815244
Comments Neurons in the human cortex have 29 800 synapses on average [primary source] resulting in a total of about 3.6×10^14 synapses. Note-29,800 synapses/neuron not found in primary source. link gives "1,000 to 10,000 synapses for a "typical" neuron." For 10^13 synapses in human cortex and 10^15 synapses in human connectome (the network of elements and connections forming the human brain) see Sporns et al., 2005 PMID 16201007 p.e42 left column bottom paragraph and right column top paragraph.
Entered by Uri M
ID 106138