"While NVLD is not classified into any distinct diagnosis in DSM-5 (American Psychiatric Association, 2013) or ICD-10 (World Health Organization, 1992), it does have a robust research base." "The majority of researchers and clinicians agree that the profile of NLD clearly exists...but they disagree on the need for a specific clinical category and on the criteria for its identification." (One researcher notes, "just because we cannot reasonably place such children into our present classification scheme does not mean they do not exist.") Assorted diagnoses have been discussed as sharing symptoms with NVLD. In some cases, especially the form of autism previously called Asperger syndrome, the overlap can be so significant as to render NVLD a pointless duplication in the mind of its detractors, with the only difference being that NVLD criteria do not mention the presence or absence of either repetitive behaviors or narrow subject-matter interests. (These are not required for a diagnosis of autism.) These overlapping conditions include, among others:

attention deficit hyperactivity disorder (ADHD)
autism spectrum disorders, especially high-functioning autism
developmental coordination disorder
social communication disorder
right hemisphere brain damage and developmental right hemisphere syndrome
social-emotional processing disorder
Gerstmann syndromeThere is diagnostic overlap between nonverbal learning disorder and autism spectrum disorder, and some clinicians and researchers consider them to be the same condition. In clinical settings, some diagnoses of attention deficit hyperactivity disorder would be more appropriately classified as NVLD.
Although AVMs are often associated with the brain and spinal cord, they can develop in other parts of the body.Normally, the arteries in the vascular system carry oxygen-rich blood, except in the case of the pulmonary artery. Structurally, arteries divide and sub-divide repeatedly, eventually forming a sponge-like capillary bed. Blood moves through the capillaries, giving up oxygen and taking up waste products, including CO2, from the surrounding cells. Capillaries in turn successively join to form veins that carry blood away. The heart acts to pump blood through arteries and uptake the venous blood.As an AVM lacks the dampening effect of capillaries on the blood flow, the AVM can get progressively larger over time as the amount of blood flowing through it increases, forcing the heart to work harder to keep up with the extra blood flow. It also causes the surrounding area to be deprived of the functions of the capillaries—removal of CO2 and delivery of nutrients to the cells. The resulting tangle of blood vessels, often called a nidus (Latin for "nest"), has no capillaries. It can be extremely fragile and prone to bleeding because of the abnormally direct connections between high-pressure arteries and low-pressure veins. The resultant sign, audible via stethoscope, is a rhythmic, whooshing sound caused by excessively rapid blood flow through the arteries and veins. It has been given the term "bruit", French for noise.