Baddeley's Model of Working Memory consists of the following four parts: the central executive, phonological loop, episodic buffer, and visuospatial sketchpad. The semantic buffer does not exist in his model, and is the correct answer. The central executive acts like the "boss" of the other three components and directs our attention. The phonologial loop gives us the ability to temporarily hold spoken or written information in our memory through repetition; for example, you use this when trying to remember a phone number. The visuospatial sketchpad allows us to temporarily remember visuospatial information via mental images. For example, you may use this when navigating through a room to remember there is a chair to your left even when it is out of sight. Last, the episodic buffer is used to relate current experiences to memories of the past. For example, if you see a house and realize it looks similar to your childhood home.

The girl in the question only remembers the last few numbers, which is known as the "recency effect." The recency effect occurs when someone attempts to memorize information and can only recall the last pieces of information that they are attempting to memorize. This likely occurs because the information is still readily available in the phonological loop, and has not yet truly been committed to memory. On the other hand, the "primacy effect" describes the opposite phenomena, when only the first pieces of information are recalled. "Encoding" is the process of transferring information from our senses to memory, and is not descriptive enough to properly answer the question. Finally, "classical conditioning" involves pairing an arbitrary stimulus with a behavior, and has more to do with learned behaviors than memory.

Alzhemier's disease is the most common form of dementia. Nerve cells in the area of the brain associated with memory and cognition are disrupted by plaques and tangles. The disease begins with mild memory loss and progresses to a point where the patient is unable to perform necessary everyday tasks.

Parkinson's disease is associated with abnormal movements, tremors, and a shuffling gait. The symptoms of Parkinson's disease are caused by a lack of the neurotransmitter dopamine, which is caused by a degeneration of neurons.

Multiple sclerosis is a chronic, progressive disorder caused by the body's immune system attacking the myelin sheathes surrounding nerve fibers in the brain, spinal cord, and optic nerves. This damage leads to muscle weakness, numbness, and vision loss.

Amyotrophic lateral sclerosis, or Lou Gehrig disease, occurs when motor neurons progressively deteriorate. This leads to muscle weakness that can progress to paralysis.

A stroke, also called a cerebral vascular accident, occurs when the blood supply to the brain is suddenly interrupted and brain cells are deprived of oxygen. The symptoms of a stroke include sudden onset of weakness, especially on one side of the body, trouble speaking, and vision disturbrances.

The hippocampus is part of the limbic system of the brain—a system that is responsible for many aspects of human functioning, including emotions and memory. The frontal lobe, which controls inhibition and attention, helps regulate executive function. The basal ganglia are situated at the base of the forebrain and are mainly comprised of striatum, the globus pallidus, the substantia nigra, the nucleus accumbens, and the subthalamic nucleus. They are associated with voluntary movement, procedural learning, and emotions, but not associated with episodic memory as the hippocampus is. The occipital lobe of the brain is at the back of the head, and is primarily associated with vision. Last, the cerebral aqueduct is part of the ventricular system in the brain and has nothing to do with higher processing.