Background: In healthy children, the frequency of anomalous persistence of primitive reflexes (PRs) and craniosacral blocks (CBs) are unknown, as well as their impact on neurodevelopment, behaviour disorders and related consequences. We aim to know the prevalence of anomalous PRs and CBs in apparently healthy children and its relationships with behavior and neurodevelopment anomalies. Methods: Participants (n=120) were evaluated through physical examination to detect PRs and CBs, an ad hoc parent survey to collect perinatal events, and children behavior assessment by teachers using Battelle score. Results: PRs were present in 89.5%. Moro (70.8%), cervical asymmetric (78.3%) and cervical symmetric PRs (67.5%) were the most frequent observed PRs. CBs were found in 83.2%, and the most frequent CBs were dura mater (77.5%) and sphenoid bone (70%) blocks. Moro, cervical asymmetric and cervical symmetric active primitive reflexes are significantly associated to cranial blocks of dura mater, parietal zones, and sphenoid bone sway. Gestational disorders or perinatal complications were associated to a higher frequency of PRs and CBs. The presence of PRs and CBs were associated with abnormal Battelle scores and neurobehavioral problems. Conclusion: Presence of PRs and CBs in children without diagnosed diseases are frequent and related with disturbances in childhood neurodevelopment.

Definition: Most multicellular animals have a nervous system that is based on the following three components: 1) Sensory cells gather information and send it to processing units; 2) the processing units use the information to decide on what action to take; and 3) effector neurons activate the appropriate muscles. Due to the importance of making the right decisions, evolution made profound advances in the processing units. I shall review present knowledge regarding the evolution of neurological tools for making decisions, here referred to as strategies or algorithms. Consciousness can be understood as a particularly sophisticated strategy. It may have evolved to allow for the use of feelings as a ‘common currency’ to evaluate behavioral options. The advanced cognitive capacity of species such as humans further improved the usefulness of consciousness, yet in biological terms it does not seem to be an optimal, fitness-enhancing strategy. A model for the gradual evolution of consciousness is presented. There is a somewhat arbitrary cutoff as to which animals have consciousness but based on current information it seems reasonable to restrict the term to amniotes.

Anterior-tooth (ANT) contacts induce short latency reflex inhibition of human jaw-closing muscles. The jaw is a rigid class 1 lever for pinpoint-targeting muscle force into a single bite-point, the pivoting food particle. See-saw reflex movements around the food particle fulcrum multiply the food-crushing force. Unpredictable jolts of reaction force caused by food-crushing are subjected to the rostral ANT and caudally to the two articulate ends of the jaw triangle. Compression/distraction strains of food-crushing must be monitored and inhibited by withdrawal reflexes. The mesencephalic ganglion (Vmes), neural myelin sheath, and muscle stretch receptors evolved subsequently to the advent of jaws to improve the velocity of proprioceptive and withdrawal reflexes. In mammalians, the spindles of the taut motor units, stretched by the food-fulcrum send excitatory monosynaptic feedback for the efferent neurons of the respective ipsilateral muscle units, via Vmes. In the Vmes, the spindle-input-mediating afferent neurons are coupled with another source of afferent feedback, which is also excitatory, from the back-tooth (BAT) mechanoreceptors. The two sources of excitatory pulses are summated and targeted for the efferent neurons to boost the stretched and taut motor units. Likewise, the afferent feedback from ANT mechanoreceptors is also coupled in the Vmes with concomitant feedback from spindles. The ANT output, however, is inhibitory to negate the excitatory feedback from the stretched jaw-muscle units. The inhibitory feed from ANT temporarily blocks the excitatory potential of masticatory motor efferent neurons to protect the ANT and jaw-joints from inadvertent strains. The inhibitory inputs from ANT alternate with the excitatory inputs from BAT to determine which jaw-closing muscle units are activated or inhibited at any given instant of food-crushing. The Vmes exists in all jawed vertebrates, and its’ evolution was probably motivated by demands for the control of bite force. The monosynaptic unilateral food-crushing excitatory and inhibitory reflexes (UFCR) override the coexisting bilaterally executed feed for jaw muscles from the central nervous system. Hypothesis: The Vmes-mediated UFCR combine neural inputs from tooth contacts with concomitant feedback from muscle stretch receptors for the control of mammalian food-crushing bite force.

Chiari malformation type 1 (CM1) includes a series of congenital anomalies that share ectopia of the cerebellar tonsils below the foramen magnum, in some cases associated with syringomyelia or hydrocephalus. CM1 can cause dysfunction of the brainstem, spinal cord, and cranial nerves. This functional alteration of the nervous system can be detected by various modalities of neurophysiological tests, such as brainstem auditory evoked potentials, somatosensory evoked potentials, motor evoked potentials, electromyography and nerve conduction studies of the cranial nerves and spinal roots, as well as brainstem reflexes. The main goal of this study is to review the findings of multimodal neurophysiological examinations in published studies of patients with CM1 and their indication in the diagnosis, treatment, and follow-up of these patients, as well as their utility in intraoperative monitoring.