Learning is defined as acquisition of information and skills. Subsequent retention of this information is called as memory. Dementia and other cognitive dysfunctions (e.g. Alzheimer's disease) pose a daunting challenge to the physicians. Since, allopathic treatment options are limited nutritional and herbal therapies are employed with proven advantage in cognitive disorders and exihibit favorable benefit-to-risk ratio. A number of medicinal plants per se and medicines derived from these plants have shown memory-enhancing properties by virtue of their medicinal constituents. One of the mechanisms suggested of dementia is decreased cholinergic activity in brain. Therefore, cholinergic drugs (of plant origin) like muscarinic agonists, nicotinic agonists and cholinesterase inhibitors can be employed for improving memory. On the other hand, herbal medicines containing cholinergic antagonists are found to produce amnesia in human beings and laboratory animals.