In the process of learning, new neurons grow in certain parts of the brain which handle sensory information. Memories are the result of changes of the ability of neurons to transfer information to other neurons of circuits started by previous neural activity. These circuits become “memory traces.” The hippocampus and the amygdala of the brain store information on memory and emotions.

Ayurvedic herbs which improve brain function are called Rasayan, and include ‘Brahmi’ (Bacopa monniera or BM,) ‘Vacha’ (Acoras calamus,) ‘Mandukaparni” (Centella asiatica,) ‘Shankhapushpi’ (Convolvulus pluricaulis,) ‘Jyotishmati’ (Celastrus paniculatus,) ‘Jatamansi’ (Nardostachys jatamansi,) and ‘Ashwagandha’ (Withania somnifera.)

BM has been shown to be especially beneficial to memory, learning, and in anxiety. BM is an antioxidant with anti-cholinesterase activity. BM is beneficial in cognitive deficit from taking phenytoin.

The present study was done to correlate the memory benefits of bacopa with histological changes of brain cells by studying dendritic changes in the neurons of the amygdalas of neonatal rats. Newborn rats were divided for 2, 4, and 6 week treatments. Each group was divided into groups for 20, 40, and 60 mg/kg of BM, daily. There was a control group which did not receive BM.

After the course of therapy, the rats were killed and the brains tissues were stained with a “Golgi stain.” Microscopic slides were studied. Eight to 10 neurons were traced with camera lucida in the amygdala of each rat. The numbers of neurons and the branches to the dendrites were counted.

The result of the study was that BM treated rats remained healthy and gained weight compared to control rats. All of the treated rats, except for those treated with only 20 mg/kg BM for 2 weeks, showed increased length and branching of dendrites. The higher doses resulted in an increase in the number of dendrites arising from the body of the neurons.

Previous studies of other herbs have shown increased dendritic arborization and increased acetylcholine levels in the brain.

CONCLUSION: Bacopa monnieri, most likely, improves memory and learning by making actual structural changes of the neurons of the amygdala, allowing improved electrical impulse conduction.

NOTE: Bacopa is used in Ayurvedic medicine for memory. Vacha is sweet flag (calamus.) (Walt Whitman, poet, wrote Calamus poems, supposedly, under the effect of calamus extract.) Centella asiatica is gotu kola. Convolvulus pluricaulis is bindweed. Celastrus paniculatus is celastrus. Nardostachys jatamansi is spikenard. Withania somnifera (Ashwagandha) is Indian ginseng.

Neurons, or nerve cells, have axons which conduct electrical impulses to the cell bodies of other neurons. They have multiple dendrites (thread-like extensions) that conduct impulses from other neurons to their neuron. The dendrites grow in a tree form with branching called arborization.

Phenytoin is a pharmaceutical anticonvulsant.

Cholinesterase inhibitors are used medically to treat dementia. Huperzine A is a cholinesterase inhibitor. Bacopa monnieri is believed to have cholinergic effects. Read a Bacopa monnieri review.

Summary #492.

PMID: 21409525.