Voices in the Brain: Disruption of the Default Network Linked to Hallucinations

Hearing voices that are not there was once thought to be a core symptom of schizophrenia and signify severe mental illness. It has been increasingly acknowledged that people with no other symptoms of schizophrenia or psychosis do hear voices [1]. There are several theories about what causes these auditory hallucinations. For example, there is good evidence that hearing voices can be linked to trauma [2]. Attempting to understand the phenomenon is not only scientifically interesting but also relates to how society views people with these experiences and if and how they may be treated. A search for how these experiences are associated with brain function is ongoing. New research published in the journal Human Brain Mapping suggests that the predisposition to hearing voices may relate to abnormal functioning of the brain whilst at rest [3].

Voices

Mad Cow Risk and Reasonable Precautions

A case of so-called “mad cow disease” was found in a California dairy cow last week. The disease, known to veterinary scientists as bovine spongiform encephalopathy (BSE), is fatal, and can be transmitted from cow-to-cow or cow-to-human through the ingestion of contaminated tissue. There is no evidence BSE spreads to humans — the human form of the disorder is called Creutzfeldt-Jakob disease — through drinking milk. As such, authorities claim that the infected animal (which is being held and will be destroyed) posed no risk to humans.

Dairy cows

Third Reported Recovery From Clinical Rabies in the U.S.

Rabies is a serious — almost always fatal — viral infection of the central nervous system. The virus is present in the saliva of infected mammals, and is most often spread via a bite wound. Raccoons, skunks, bats, foxes, and coyotes are the most common carriers of rabies in the United States, though any mammal, including domestic dogs and cats, can become infected and transmit the disease. The U.S. Centers for Disease Control and Prevention keeps statistics on rabies incidence in the U.S., and notes that cases are quite rare. Only one or two individuals a year become infected with the rabies virus, and prophylaxis (vaccination post-exposure, but prior to the development of symptoms) is almost always effective.

Bat