How nitric oxide helps update memories

Neurotransmitters are integral to the brain's communication system, enabling neurons to transmit signals across synapses. This chemical exchange underpins various cognitive functions, including memory processes. The role of neurotransmitters in memory is multifaceted, influencing the encoding, consolidation, and retrieval of memories through their action on different neural circuits.
 Glutamate and Synaptic Plasticity
Glutamate, the brain's main excitatory neurotransmitter, is...

Nitric oxide (NO), an inorganic gas, acts as a potent second messenger in most animal and plant tissues. NO diffuses out of the cells that produce it and enters the neighboring cells to generate a downstream response. NO synthase (NOS) catalyzes NO production by the deamination of the amino acid arginine. There are three isoforms of NOS. Endothelial cells have endothelial NOS (eNOS), nerve and muscle cells have neuronal NOS (nNOS), and macrophages produce inducible NOS (iNOS) upon exposure...

Cognitive enhancers, also known as "smart drugs," are substances used to enhance memory, mental alertness, and concentration. These can be natural or synthetic and improve cognition in conditions like Alzheimer's disease (AD) and other neurodegenerative diseases. Some common examples include caffeine, amphetamines, methylphenidate, modafinil, arecoline, donepezil, vortioxetine, and piracetam. These enhancers work on the principle of synaptic plasticity and altered circuit function.

The cerebellum, while traditionally associated with motor control, also plays a crucial role in memory, particularly in procedural memory, which involves learning motor tasks that become automatic through repetition. For example, studies have shown that when the cerebellum is damaged, individuals or animals lose the ability to learn conditioned motor responses, such as the conditioned eye-blink response in classical conditioning experiments with rabbits. This study demonstrates the...

The hippocampus, a critical brain structure, plays an essential role in memory processing, particularly in the formation and retrieval of memory. This small, seahorse-shaped region is located within the medial temporal lobe, with one hippocampus in each brain hemisphere. Experimental studies involving lesions in the hippocampi of rats have demonstrated significant impairments in tasks such as object recognition and maze navigation, indicating the hippocampus involvement in both recognition and...

Memory is the retention of information or experiences over time, facilitated through three main processes: encoding, storage, and retrieval. Encoding is the process of inputting information into the memory system. For instance, when listening to a lecture, watching a play, reading a book, or having a conversation, the brain is actively encoding information. This initial stage involves transforming sensory input into a form that can be processed and stored by the brain. Various factors, such as...