Learning as a possible sign of non-reflective consciousness in persons with a diagnosis of vegetative state and pervasive motor impairment

Abstract

A diagnosis of vegetative state represents a serious predicament, which basically precludes/minimizes rehabilitation perspectives. Reliability of the assessment approach in these situations is of paramount importance, but not easy to achieve. In recent studies, a learning assessment procedure has been suggested as a supplement in the diagnostic process and assessed with eight patients. The procedure involves an ABABCB sequence in which A represents baseline phases with no stimulation available, B intervention phases with stimuli delivered contingently on target responses, and C a control condition. This condition involves stimulation presented non-contingently. The patients' ability to associate responding with environmental stimuli and thus increase such responding during the B phases, and reduce it during the A and C phases, may be considered a sign of learning. Learning might be viewed as representative of forms of concrete knowledge and presumably basic levels of consciousness. Preliminary results indicate that (a) signs of learning may appear in patients with a previous diagnosis of vegetative state and (b) the presence of those signs may require a revision of their diagnostic label and a reappraisal of their rehabilitation perspectives.

Microswitch technology and contingent stimulation to promote adaptive engagement in persons with minimally conscious state: a case evaluation

“…The massage stimulation consisted of light stroking of Nicolette's shoulders, head, and neck (see Lancioni et al 2011). This form of stimulation was added to the music, on the assumption that it might be pleasant and increase the assumedly positive (conceivably reinforcing) value of the music per se (Bosco et al 2009;Lancioni et al 2011). …”

“…A diagnosis of minimally conscious state and extensive motor impairment is commonly associated with a person displaying some form of adaptive responding (i.e., engagement with environmental events), which might improve as a consequence of intervention/rehabilitation programs (Bosco et al 2009;Canedo et al 2002;Coleman and Pickard 2011;Giacino and Kalmar 2005;Giacino and Trott 2004;Lancioni et al 2009a, b;Laureys and Boly 2007). Intervention programs may be more likely to produce positive effects if adequate intervention strategies are carefully applied.…”

Vegetative state: efforts to curb misdiagnosis

“…Learning may be defined as a process by which a person acquires knowledge on the relationship between responses and environmental events, suggesting a non-reflective level of phenomenal consciousness (Bosco et al 2009;Schacter 1997;Sun et al 2007). The aforementioned studies by Lancioni et al involved 11 persons with a diagnosis of vegetative state and pervasive motor disabilities.…”

Assessment and Intervention with Patients with Severe Disorders of Consciousness

“…The Coma Recovery Scale-Revised (CRS-R) is considered to be the most dependable scale for identifying sensory and communication expressions or responses to objects that serve to determine the patient's level of functioning (Boly 2011;Bosco et al 2010;Bruno et al 2011;Doig and Lane-Brown 2012;Godbolt et al 2012;Kalmar and Giacino 2005;La Porta et al 2013;Schnakers et al 2009;Seel et al 2010;Shiel et al 2000). Problems with this scale (and similar scales) are likely to arise when patients do not possess the hand and head responses relevant for some of the scale items and/or are unable to comprehend verbal instructions (Bosco et al 2009;Di Perri et al 2016;Lancioni et al 2014a;Owen and Coleman 2008;SchmitterEdgecombe 2006).…”

“…The other is based on operant learning principles (Pierce and Cheney 2008) and is aimed at assessing the patients' ability to associate a response with the stimulation that follows it (Lancioni et al 2009a(Lancioni et al , 2014a. Signs of learning within either strategy (i.e., the achievement of an association between events) may be taken to suggest a non-reflective level of phenomenal consciousness, and thus to support a diagnosis of minimally conscious state (Bekinschtein et al 2009;Bosco et al 2009Bosco et al , 2010Lancioni et al 2009bLancioni et al , 2014a. Learning test strategies may be seen as critically relevant for patients who have only basic/minimal responses, such as eyelid or lip movements (i.e., patients who are likely to have problems with the CRS-R).…”