Akinesia in Parkinsonism. Relation between spontaneous movement (other than tremor) and voluntary movements made on command

Abstract

Tremor, rigidity and motor fatiguing These were assessed clinically (table 1). Motor fatiguing was evaluated while the patient actively opposed the four finger tips, one after another, to the thumb of the same hand. One series of oppositions followed another. Fatiguing was rated as the overall decline in speed and amplitude that occurred despite the patient's efforts to sustain the activity. Standardised tasks of voluntary movement (a) Placing clotbespegs on line: six wooden clothespegs, each activated by a metal spring, were clipped to the edge of a thin board fixed.at the level of the subject's waist. The time was taken for him to place all six, one by one, on a clothesline held level with his eyes. On each day of testing he made three scoring runs with the right hand (moving six pegs for each run). The times for the three runs were added together to determine his rating for that day. A similar procedure was followed for the left hand.(b) pegboard test: the time was taken for the patient's right hand to move 35 cylindrical metal pegs in a predetermined order from holes in the left half of the pegboard to a corresponding set of vacant holes in the right 582 by copyright.

Isolated forearm – or isolated brain? Interpreting responses during anaesthesia – or ‘dysanaesthesia’

“…We can only speculate: the level of surgical stimulus is inadequate or too uninteresting to hold the IFT‐responder's attention (whereas the verbal command compels). This is akin to Carpenter's ‘cortical threshold’ model, wherein the subject is often aware of only one of several objects in the visual field, and saccadic eye movements are initiated to bring the focus of attention to that object ; the IFT‐responder is dreaming (note that some authors regard dreaming as partial consciousness ) and satisfactorily incorporating surgical stimuli into their dream; a verbal command, however, is sufficiently specific and disruptive to evoke a response; the IFT‐responder is in a state akin to Parkinson's disease where there is poverty of spontaneous movement, yet a near‐normal movement to command . Why this would be so is unknown, but anaesthesia may be influencing the ability to initiate movement, regardless of neuromuscular blockade ; the IFT‐responders spontaneously try to move the wrong (paralysed) arm, but on command are able to move the ‘correct’ (unparalysed) arm as instructed.…”

Testing the contributions of striatal dopamine loss to the genesis of parkinsonian signs

“…Bradykinesia refers exclusively to slowed execution of movement (measurable as prolonged movement durations, MDs, Hallett and Khoshbin, 1980), while rigidity and tremor manifest as increased muscular resistance to passive joint movement and involuntary 4–6 Hz tremulous movements of one or more body part, respectively (Jankovic, 2008). Each of these parkinsonian signs varies independently in severity, rate of progression, and response to therapy (Espay et al, 2009; Evarts et al, 1981; Jankovic, 2008; Jordan et al, 1992; Kimber et al, 1999; Kishore et al, 2007; Meyer, 1982; Nieuwboer et al, 1998; Selikhova et al, 2009; Temperli et al, 2003; Zetusky and Jankovic, 1985), implying that different parkinsonian signs may have unique pathophysiologic substrates. Similarly, the fact that anatomically-segregated regions of the striatum are devoted to skeletomotor, associative and limbic functions (Alexander et al, 1990; Kelly and Strick, 2004; Worbe et al, 2009) has prompted proposals that dissociable symptoms of PD arise from loss of DA from separate functional regions of the striatum (Alexander et al, 1986; Joel and Weiner, 1994; Wichmann et al, 2011).…”