Simple partial seizures are seizure

Seizure

An epileptic seizure, occasionally referred to as a fit, is defined as a transient symptom of "abnormal excessive or synchronous neuronal activity in the brain". The outward effect can be as dramatic as a wild thrashing movement or as mild as a brief loss of awareness...

s which affect only a small region of the brain, often the temporal lobes and/or hippocampi. People who have simple partial seizures retain consciousness. Simple partial seizures are often precursors to larger seizures, where the abnormal electrical activity spreads to a larger area of (or all of) the brain, usually resulting in a complex partial seizure

Complex partial seizure

A complex partial seizure is an epileptic seizure that is associated with bilateral cerebral hemisphere involvement and causes impairment of awareness or responsiveness, i.e. loss of consciousness.-Presentation:...

 or a tonic-clonic seizure

Tonic-clonic seizure

Tonic–clonic seizures are a type of generalized seizure that affects the entire brain...

. In this case they are often known as an aura

Aura (symptom)

An aura is a perceptual disturbance experienced by some migraine sufferers before a migraine headache, and the telltale sensation experienced by some people with epilepsy before a seizure. It often manifests as the perception of a strange light, an unpleasant smell or confusing thoughts or...

.

Presentation

Simple partial seizures are a very subjective experience, and the symptoms of a simple partial seizure vary greatly between people. This is due to the varying locations of the brain the seizures originate in, and a simple partial seizure may go unnoticed by others or shrugged off by the sufferer as merely a "funny turn". Simple partial seizures usually start suddenly and are very brief It is unusual for them to occur in isolation as they usually lead to other forms of partial seizure

While awake some common symptoms of simple partial seizures are:

• preserved consciousness
• sudden and inexplicable feelings of fear, anger, sadness, happiness or nausea
• experiencing of unusual feelings or sensations
• altered sense of hearing, smelling, tasting, seeing, and tactile perception (sensory illusion
  Illusion
  An illusion is a distortion of the senses, revealing how the brain normally organizes and interprets sensory stimulation. While illusions distort reality, they are generally shared by most people....
  
  s and/or hallucinations), or feeling as though the environment is not real (derealization
  Derealization
  Derealization is an alteration in the perception or experience of the external world so that it seems unreal. Other symptoms include feeling as though one's environment is lacking in spontaneity, emotional coloring and depth. It is a dissociative symptom of many conditions, such as psychiatric and...
  
  ) or detachment from the environment (depersonalization
  Depersonalization
  Depersonalization is an anomaly of the mechanism by which an individual has self-awareness. It is a feeling of watching oneself act, while having no control over a situation. Sufferers feel they have changed, and the world has become less real, vague, dreamlike, or lacking in significance...
  
  )
• a sense of spatial distortion—things close by may appear to be at a distance.
• déjà vu
  Déjà vu
  Déjà vu is the experience of feeling sure that one has already witnessed or experienced a current situation, even though the exact circumstances of the prior encounter are uncertain and were perhaps imagined...
  
   (familiarity) or jamais vu
  Jamais vu
  In psychology, jamais vu is the phenomenon of experiencing a situation that one recognises but that nonetheless seems very unfamiliar.-Linguistics:...
  
  (unfamiliarity)
• laboured speech or inability to speak at all
• usually the event is remembered in detail

When the seizure occurs during sleep, the person will often become semi-conscious and act out a dream while engaging with the environment as normal, and objects and people usually appear normal or only slightly distorted, being able to communicate with them on an otherwise normal level. However, since the person is acting in a dream-like state, they will assimilate any hallucinations or delusions into their communication, often speaking to a hallucinatory person or speaking of events or thoughts normally pertaining to a dream or other hallucination.

While asleep symptoms include:

• onset usually in REM sleep
• dream like state
• appearance of full consciousness
• hallucinations and/or delusions
• behavior or visions typical in dreams
• ability to engage with the environment and other people as in full consciousness, though often behaving abnormally, erratically, or failing to be coherent
• complete amnesia or assimilating the memory as though it was a normal dream on regaining full consciousness

Although hallucinations may occur during simple partial seizures they are differentiated from psychotic symptoms by the fact that the person is usually aware that the hallucinations are not real.