NeuroExplorer

Deep brain stimulation (DBS) is a surgical procedure used for patients who do not respond to medication. This technique can be used for patients with neurological disorders, such as Parkinson's disease , to reduce symptoms such as tremors or muscular rigidity. DBS involves implanting a small device (an electrode) similar to a pacemaker that sends electrical signals to interfere with and block abnormal brain signals. The device is connected to a pulse stimulator attached to the back or the chest. Before beginning the procedure, the neurosurgeon determines where to implant the device by imaging the brain using MRI or CT scans. Since Parkinson's patients have damaged neurons in parts of the basal ganglia, (read more) the device is usually placed in the globus pallidus or the subthalamic nucleus (pictured below).                                                                                                                      ________ Image Credit: (1) “Basal Gangl

The cerebrum is the largest part of the human brain that is divided into two hemispheres. These hemispheres are connected by a bundle of nerve fibers known as the corpus callosum , which allows the hemisphere to communicate with each other. The cerebrum is divided into four lobes that each have a unique function (pictured below). The frontal lobe  is directly above the eyes at the front of the brain. It controls voluntary movement, speech, memory, emotion, and higher cognitive skills such as planning and problem-solving. The parietal lobe , located behind the frontal lobe, receives sensory signals and processes taste. The occipital lobe located at the back of the cerebrum processes visual information and the temporal lobe , located at the side of the brain, interprets auditory information.                                                                                                                      ________ Image Credit: (1)“Cerebrum Lobes.” Wikimedia Commons, uplo

Down syndrome is a neurological childhood disorder that is prevalent in about 250,000 people in the United States. Children with Down syndrome have distinctive facial features including a flattened face and bridge of the nose, eyes that slant upward, and small ears. They usually have low to moderate intellectual ability. Down syndrome is caused by an extra copy of the 21st chromosome in a person's cells, known as trisomy 21 . This means that, instead of having two copies of chromosome 21, they have three copies (pictured below). In rare cases, the extra copy may not be present in every cell — a condition known as mosaic down syndrome.  People with mosaic Down syndrome have milder symptoms and a longer life expectancy. There is no clear cause for trisomy 21, although maternal age can be a risk factor. People with Down syndrome are at a higher risk of developing early-onset Alzheimer's disease. Chromosome 21 contains the gene that codes for the amyloid precursor prot

Parkinson's disease (PD) is a neurodegenerative disease in which patients experience tremors, rigidity, and akinesia (the inability to move). After Alzheimer's, it is the second most common neurodegenerative disease (which involves progressive destruction of nerve cells). Parkinson's disease is characterized by the loss of dopaminergic neurons in the substantia nigra, a region of the basal ganglia in the brain (pictured below). As the name suggests, dopaminergic neurons produce dopamine, a critical neurotransmitter associated with motor control. This loss of dopamine leads to the hallmark symptoms of PD — tremors, muscular rigidity, and slow movement. Over time, the symptoms may worsen as patients begin to experience cognitive decline and develop emotional changes such as depression. The exact cause of Parkinson's is not entirely clear, but a combination of genetics and the environment appears to be the culprit. The disease is linked to a mutation in the PARK

The central dogma is a fundamental concept of biology. It describes the two step process of gene expression: transcription followed by translation. This allows a protein to be created from a gene. DNA  →   RNA   →  Protein During the first step, the genes in a DNA template are transcribed  to create a single strand of mRNA. Once the mRNA leaves the cell's nucleus, it is translated  into a protein at the ribosome in the cell's cytoplasm.