NLD involves deficits in perception, coordination, socialisation, non-verbal problem-solving and understanding of humour, along with well-developed rote memory. As most people with Asperger syndrome (AS) fit the criteria for NLD, a diagnosis of AS is often preferred.
In this instance, some researchers assert that an AS diagnosis is more clinically useful than an NLD diagnosis, and argue that NLD would be an example of excessive diagnostic splitting. However, NLD can also occur with other disorders. However, like Asperger syndrome, NLD exists on a spectrum, and those affected can experience it in a range of ways.
Those with an NLD diagnosis can experience some or all of the symptoms, and to varying degrees. Ongoing debate surrounds the relationship between Asperger syndrome and NLD, as research on the condition is ongoing and procedures can differ from AS research.
Non-verbal communicationPeople with this disability may misunderstand non-verbal communications, or they may understand the communications but be unable to formulate an appropriate response. This can make establishing and maintaining social contacts difficult.
Eye contact can also be difficult for people with NLD, either because they are uncomfortable with maintaining it or because they do not remember that others expect it. Similarly, knowing when and how to use physical contact and recognizing emotions in others and expressing them for oneself can be problematic.
Verbal communicationPeople with NLD will often tend to lapse into "cocktail-speech," talking too much and too quickly. People with NLD have strong verbal communication skills and must often rely on verbal communication as their main method of gathering information.
Trying to process too many non-verbal stimuli can confuse them.
People with NLD often have strong verbal skills, and learn how to use those to compensate.
Numerical and spatial awarenessArithmetic and mathematics can be very difficult for people with NLD, and they often have problems with spatial awareness. Problematic areas may include:
- Recognising faces
- Paying attention in noisy environments
- In mathematics: the confusion of X-axis and Y-axis
- Remembering the names and locations of places
- Map reading, or plotting or remembering routes. People with NLD are often best-served by giving landmarks along with repeated directions.
- Estimating the speed of cars while crossing the road
- Self-awareness of where their body is(frequently bump into other people and objects)
- Backing out a car
MotorPeople with NLD often have motor difficulties. This can manifest in their walking and running, which are sometimes stiff, or in difficulty balancing. They may also be more likely to run into things, due to judging distances poorly.
Fine motor skills can also develop abnormally, causing difficulty with writing, drawing, and tying shoelaces. NLD sufferers are often labeled as "clumsy" or "stiff".
AnxietyPeople with NLD, more than many others, fear failure. They may feel that they have to do too much at once, and then do not know where to start. This allows them to stagnate, and then do nothing. Sometimes they try to multitask and again end up doing nothing, which can lead to frustration.
They may experience the world around them as a chaos, the actions that they must perform well and quickly creating a sense of helplessness.
Clumsiness in performing tasks may be criticised by teachers or in the workplace, causing further fear of failure.
There is a high incidence of suicide in the NLD population.