First, what's a dendrite? A dendrite is:
a short extension of a neuron which receives inputs from other nerve cells at synapses transmitted to the cell body.
A neuron is just a brain cell or nerve cell. A synapse is a gap that neurotransmitters diffuse across.
Dendrites are branched and short, unlike axons which are long and unbranched. In the figure below the soma is the cell body of a neuron.
Vollala and colleague asked whether Bacopa monnieri extract could affect brain morphology in adult rats 1. (In biology, morphology refers to the structural features of an organ or tissue.)
Vollala found that Bacopa increased dendritic intersections and branch points along the length of both apical and basal dendrites. This effect only manifested after 6 weeks of Bacopa treatment. At the 2 week mark, no effect was observed. This underscores how nootropics take time to work.
How should we interpret these changes in dendritic morphology? What if they are undesirable, abnormal changes? The authors considered this possibility and addressed it with learning and memory tests.
It turned out that changes in dendritic morphology also corresponded with improvements in spatial learning and memory retention. Moreover, environmental enrichment alone enhances dendritic branching in the hippocampus of rats. Hence, a crude interpretation would be that Bacopa recapitulates the beneficial effects of environmental novelty.