PT  - JOURNAL ARTICLE
AU  - André B. Valdez
AU  - Megan H. Papesh
AU  - David M. Treiman
AU  - Kris A. Smith
AU  - Stephen D. Goldinger
AU  - Peter N. Steinmetz
TI  - Distributed Representation of Visual Objects by Single Neurons in the Human Brain
AID  - 10.1523/JNEUROSCI.1958-14.2015
DP  - 2015 Apr 01
TA  - The Journal of Neuroscience
PG  - 5180--5186
VI  - 35
IP  - 13
4099  - http://www.jneurosci.org/content/35/13/5180.short
4100  - http://www.jneurosci.org/content/35/13/5180.full
SO  - J. Neurosci.2015 Apr 01; 35
AB  - It remains unclear how single neurons in the human brain represent whole-object visual stimuli. While recordings in both human and nonhuman primates have shown distributed representations of objects (many neurons encoding multiple objects), recordings of single neurons in the human medial temporal lobe, taken as subjects' discriminated objects during multiple presentations, have shown gnostic representations (single neurons encoding one object). Because some studies suggest that repeated viewing may enhance neural selectivity for objects, we had human subjects discriminate objects in a single, more naturalistic viewing session. We found that, across 432 well isolated neurons recorded in the hippocampus and amygdala, the average fraction of objects encoded was 26%. We also found that more neurons encoded several objects versus only one object in the hippocampus (28 vs 18%, p < 0.001) and in the amygdala (30 vs 19%, p < 0.001). Thus, during realistic viewing experiences, typical neurons in the human medial temporal lobe code for a considerable range of objects, across multiple semantic categories.