Alzheimer's disease & dementia

Neuronal cytoskeletons involved in Alzheimer's disease

A researcher at the UPV/EHU participated in a study describing the loss of dynamics and subsequent impairment of the dendritic spines in Alzheimer's disease. Dendritic spines are the compartments of neurons responsible for ...

Neuroscience

How the human brain works during simultaneous interpretation

Researchers at the Centre for Bioelectric Interfaces and the Centre for Cognition & Decision Making of the Higher School of Economics utilized electroencephalogram (EEG) and the event-related potential (ERP) technique to ...

Neuroscience

A new hope in treating neurodegenerative disease

Korean researchers have identified the inhibition of autophagy in microglia, brain immune cells. It is expected to help develop treatments for Alzheimer's disease which occur due to the inhibition of autophagy.

Alzheimer's disease & dementia

Frailty could make people more susceptible to dementia

New research published in The Lancet Neurology journal suggests that frailty makes older adults more susceptible to Alzheimer's dementia, and moderates the effects of dementia-related brain changes on dementia symptoms. The ...

Genetics

Mapping the neural circuit of innate responses to odors

A team of neuroscientists at the Champalimaud Centre for the Unknown (CCU), in Lisbon (Portugal), has performed one of the first studies into the central neural circuits (or higher brain areas) that underlie innate responses ...

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Brain

The brain is the center of the nervous system in all vertebrate, and most invertebrate, animals. Some primitive animals such as jellyfish and starfish have a decentralized nervous system without a brain, while sponges lack any nervous system at all. In vertebrates, the brain is located in the head, protected by the skull and close to the primary sensory apparatus of vision, hearing, balance, taste, and smell.

Brains can be extremely complex. The cerebral cortex of the human brain contains roughly 15-33 billion neurons depending on gender and age, linked with up to 10,000 synaptic connections each. Each cubic millimeter of cerebral cortex contains roughly one billion synapses. These neurons communicate with one another by means of long protoplasmic fibers called axons, which carry trains of signal pulses called action potentials to distant parts of the brain or body and target them to specific recipient cells.

The most important biological function of the brain is to generate behaviors that promote the welfare of an animal. Brains control behavior either by activating muscles, or by causing secretion of chemicals such as hormones. Even single-celled organisms may be capable of extracting information from the environment and acting in response to it. Sponges, which lack a central nervous system, are capable of coordinated body contractions and even locomotion. In vertebrates, the spinal cord by itself contains neural circuitry capable of generating reflex responses as well as simple motor patterns such as swimming or walking. However, sophisticated control of behavior on the basis of complex sensory input requires the information-integrating capabilities of a centralized brain.

Despite rapid scientific progress, much about how brains work remains a mystery. The operations of individual neurons and synapses are now understood in considerable detail, but the way they cooperate in ensembles of thousands or millions has been very difficult to decipher. Methods of observation such as EEG recording and functional brain imaging tell us that brain operations are highly organized, but these methods do not have the resolution to reveal the activity of individual neurons.

This text uses material from Wikipedia, licensed under CC BY-SA