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  • Updated 08.23.2019
  • Released 08.23.2019
  • Expires For CME 08.23.2022

Automatic-voluntary dissociation


This article includes discussion of automatic-voluntary dissociation. The foregoing terms may include synonyms, similar disorders, variations in usage, and abbreviations.


Automatic-voluntary dissociation is the differential completion of an action depending on the patient’s attention to the task. Activities can be performed either attentively (“voluntarily”) or inattentively (“automatically”). Thus, 2 kinds of automatic-voluntary dissociation can occur. The kind that is more often described refers to the patient’s inability to complete an action voluntarily (attentively), but ability to do so automatically (inattentively). Less often described is the dissociation whereby activities are completed voluntarily, but not automatically, although this kind of dissociation is actually common. Recognizing automatic-voluntary dissociation in a patient may suggest potential methods for therapy for the concerned impairment, some of which have been developed. In this article, the author reviews the many different manifestations of this phenomenon and discusses its implications for patient management.

Key points

• Automatic-voluntary dissociation refers to the differential completion of an action depending on the individual’s attention to it.

• The dissociation is not specific to a form of neuropathology or lesion localization.

• The dissociation can occur in either direction. Some illnesses or conditions result in relatively preserved “automatic” acting (involving reduced attention or effort) but impaired “voluntary” acting (involving increased attention or effort), whereas others have the opposite pattern. In addition, some illnesses can have both forms of dissociation.

• Automatic-voluntary dissociation teaches that formal clinical testing that requires performing on command (which requires attention to the task) may underestimate or overestimate the ability to complete the same activity under spontaneous, real-world circumstances.

• Management for automatic-voluntary dissociation is not well developed.

Historical note and terminology

Clinicians commonly note that chronic nonepileptic brain disorder symptoms are constant for at least several minutes. For example, aphasia or limb paresis are considered to persist without change over short stretches of time. However, for nearly 200 years researchers have noted that the ability of some patients to accomplish specific activities can change drastically, quickly, and abruptly following changes in the immediate environment, within their bodies, or in their social interactions. The critical factor is whether the patient pays attention to the action.

“Automatic-voluntary dissociation” refers to the completion of an action depending on whether the patient attends to the action. By convention, “voluntary” mediation involves deliberate attention to the activity. “Automatic” mediation, in contrast, occurs inattentively or with minimal perceived effort (42). Other published terms for this phenomenon are “automatico-voluntary dissociation” and, in the French literature, “dissociation automaticovolontaire.” It has also historically been called the “Baillarger-Jackson principle” (13), a term that is no longer used.

Automatic-voluntary dissociation has been reported since the observation of impaired voluntary mouth closure despite preserved spontaneous smiling following stroke in the early 19th century (75). Automatic-voluntary dissociation was formally recognized, particularly in aphasia, in the contemporary but independent observations of François Baillarger (1809-1890) in France and John Hughlings Jackson (1835-1911) in England (03). Jackson’s observations are more widely recognized, but Jackson himself credited Baillarger with having first recognized this phenomenon (54).

Automatic-voluntary dissociation may be observed on novel tasks as, for example, when patients with Parkinson disease must manually track an unpredictably moving stimulus (41). However, for the most part, the behaviors that will be discussed in this article are reported during routine activities of daily living or tests of familiar activities.

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