A Reflex Action is a Simple Or Unconditioned Or Natural Reflex action.
Brain Pathology - the Pathologic conditions affecting the BRAIN, which is composed of the intracranial components of the CENTRAL NERVOUS SYSTEM.
Reflexes are of two types: Simple or unconditioned or natural reflex. In this type of reflex, the brain is not involved.
Control of ventilation (respiration) refers to the physiological mechanisms involved in the control of physiologic ventilation.
The most important function of breathing is gas exchange (of oxygen and carbo dioxide). Thus the control of respiration is centered primarily on how well this is achieved by the lungs.
The pattern of motor stimuli during breathing can be divided into inspiratory and expiratory phases.
Exhalation is usually silent, except at high minute ventilation rates.
The mechanism of generation of the ventilatory pattern is not completely understood, but involves the integration of neural signals by respiratory control centers in the medulla and pons.
Ventilation is normally controlled by the autonomic nervous system, with only limited voluntary override. An exception to this is Ondine's curse, where autonomic control is lost.
Primitive reflexes are reflex actions originating in the central nervous system that are exhibited by normal infants but not neurologically intact adults, in response to particular stimuli. These reflexes disappear or are inhibited by the frontal lobes as a child moves through normal child development. These primitive reflexes are also called infantile, infant or newborn reflexes.
Older children and adults with atypical neurology (for instance, people with cerebral palsy) may retain these reflexes and primitive reflexes may re-appear in adults because of certain neurological conditions including, but not limited to, dementia, traumatic lesions, and strokes.
Newborn babies have a number of other reflexes which are not seen in adults (primitive reflexes) are: Asymmetrical tonic neck reflex (ATNR), Grasp reflex, Hand-to-mouth reflex, Moro reflex (startle reflex), Rooting reflex, Sucking reflex, Symmetrical tonic neck reflex (STNR) and Tonic labyrinthine reflex (TLR).
Many reflexes are quite complex requiring a number of synapses in a number of different nuclei in the CNS (e.g., the escape reflex). Others involve a couple of synapses to function (eg., the withdrawal reflex). Processes such as breathing, digestion, and the maintenance of the heartbeat are also regarded as reflex actions.
