Regression-predicted and FE-reaction “canine” bite forces in <i>Basilosaurus isis</i>.

<p>Regression-predicted and FE-reaction “canine” bite forces in <i>Basilosaurus isis</i>.</p

Jaw muscles of <i>Basilosaurus isis</i> and constraints for FEA.

<p>A. Jaw muscles of <i>B</i>. <i>isis</i> and muscle vector and moment arms for leverage-based force calculation. B. Adductors (red arrows) mapped onto a CT-based finite element model of the cranium of <i>Basilosaurus isis</i> WH-74, including the dentaries. C. Constraints for finite element analyses. In the all-muscles active analysis, the cranium was fully constrained at the left and right temporomandibular joints (TMJ), and tooth constraints were applied in respective bite analyses. In the posterior shear analysis, the only active muscles are the posterior temporalis, and only P³ is constrained.</p

Inputs and results for estimating adductor muscle forces in <i>Basilosaurus isis</i>, assuming 30 N/cm² baseline isometric specific tension (ST).

<p>Inputs and results for estimating adductor muscle forces in <i>Basilosaurus isis</i>, assuming 30 N/cm² baseline isometric specific tension (ST).</p

Exploratory plate-model distribution of von Mises stresses.

<p>Von Mises stresses (σ_vM; maximum shown here of 20 MPa) in <i>Basilosaurus isis</i> biting on its upper third premolar, assuming muscle specific tension of 37 N/cm². Oblique view. Note an arc of evident stress in the maxilla dorsal to the bite point, and muscle-induced stresses from the force of m. temporalis.</p

Sensitivity of P³ von Mises stresses and reaction forces to plate element thickness and a solid volume mesh.

<p>Note that bite force estimates at the third premolar (<i>F</i>_<i>P3</i>, black bars, right scale) are consistent (16,453 N-16,483 N) regardless of plate element thickness. By contrast, peak von Mises stresses (red bars, left scale) vary widely with varying plate thickness, from 399 MPa at 5 mm plate thickness to only 160 MPa at 10 mm thickness, and 64 MPa at a realistic 20 mm. These results indicate that plate element FEA is precise and useful for estimating bite forces, but not recommended for estimating stress magnitudes unless element thickness matches that of the original structure. <i>F</i>_<i>P3</i> for the volume mesh is 16,541 N and peak stress is 51 Pa.</p

<i>Basilosaurus isis</i> bite force estimates (N) compared with other long-skulled carnivores, including skull length and method.

<p><i>Basilosaurus isis</i> bite force estimates (N) compared with other long-skulled carnivores, including skull length and method.</p

Reaction forces and von Mises stresses with unilateral bites in <i>Basilosaurus isis</i>.

<p>Reaction forces and von Mises stresses with unilateral bites in <i>Basilosaurus isis</i>.</p

Descriptive results of neuropsychological assessments administered to patients with ALS and healthy controls.

<p>COWAT = Controlled Oral Word Association Test; VFI = verbal fluency index; MoCA = Montreal Cognitive Assessment; ALS-CBS = ALS Cognitive Behavioral Screen; ELQ = Emotional Lability Questionnaire from person with ALS; ELQ Family = Emotional Lability Questionnaire from relatives and caregivers.</p><p>Descriptive results of neuropsychological assessments administered to patients with ALS and healthy controls.</p

Experiment 2 Action Understand > Observe, HC > ALS.

<p>Greater activity in the HC group compared to patients with ALS throughout the right prefrontal cortex and temporal regions shown for the <i>understand>observe</i> contrast from Experiment 2.)</p

Example of a trial from each condition (action-observation and action-execution) in Experiment 1.

<p>Example of a trial from each condition (action-observation and action-execution) in Experiment 1.</p