Parasympathetic nervous system

Rapid eye movement sleep is a unique phase of mammalian sleep characterized by random movement of the eyes, low muscle tone throughout the body, and the propensity of the sleeper to dream vividly. This phase is also known as paradoxical sleep and sometimes desynchronized sleep because of physiological similarities to waking states, including rapid, low-voltage desynchronized brain waves. Electrical and chemical activity regulating this phase seems to originate in the brain stem and is…

I. Subject and Grade Level: 4th Grade, Science II. Topic: Waves III. Standards: State: 4-PS4-1. Develop a model of waves to describe patterns in terms of amplitude and wavelength and that waves can cause objects to move. 4-PS4-3. Generate and compare multiple solutions that use patterns to transfer information. National: 4-PS4-1. Develop a model of waves to describe patterns in terms of amplitude and wavelength and that waves can cause objects to move. 4-PS4-3. Generate and compare…

Early visual experience is essential for the maturation of visual functions. For example, behavioral studies have demonstrated that visual acuity is low at the time of eye opening and visual experience is indispensable for its developmental improvement (Maurer et al., 1999; Prusky et al., 2000; Kang et al., 2013). Visual cortical neurons selectively respond with a higher rate of action potentials to particular features of visual stimuli (Hubel, 1982), which is considered to be a fundamental…

Epilepsy is a common nervous system disorder that is described by sudden and recurrent seizures [1]. World Health Organization (WHO) statistics show that approximately 50 million people worldwide currently suffer from epilepsy [2]. Epileptic seizures are categorized into focal (also called partial), generalized, and unclassified. In the focal seizures, the abnormal electrical discharges start with a localized region, whereas in the generalized seizures, the abnormal electrical discharges start…

Subplate neurons are one of the earliest formed neurons in the cerebral cortex and play a critical role in cortical development and maturation. Specifically, they receive information from the thalamus and project unto the developing cortical plate. The cortex is comprised of a six-layers and subplate neurons are found in the developing white matter below layer 6. During critical periods, these neurons are necessary for the arrangement and improvement of thalamocortical connections. Subplate…

Nystagmus refers to involuntary eye movements which are usually in the horizontal axis but can also be vertical or torsional. 1 According to the speed of the fast and slow phases, nystagmus is classified as pendular or jerky and based on the time of onset, into congenital (or infantile) and acquired types. 1-4 Infantile nystagmus syndrome (INS) may be further classified into sensory and motor types. In patients with sensory type, there is a recognizable structural abnormality leading to…

It is critical to survival the ability to distinguish between a dangerous and a safe context. A place with aversive connotations generates a fear memory associated to a context; however, when the same place becomes safe, after reexposure, an extinction memory is generated (LeDoux, 2000). Therefore, both the fear and the extinction memory are evoked by the same context, and after some time, the fear memory usually persists and overcomes the extinction memory (Sotres-Bayon et al., 2006; Ji and…

Introduction: regular weight individuals are less likely to have depressive symptoms than overweight or underweight persons. Depression is going to b to be the second reason of universal encumbrance disease by 2020. One of the reasons which causes depression is declining of BDNF which is considered as neurogenesis factor. brain-derived neurotrophic factor (BDNF) can be declined by increasing of stress. Additionally, the expression of BDNF in the brain can be raised by prolonged antidepressant…

Reading about the parts of the brain really changed my perception about how important each part of the brain is. If I had to choose two parts of my brain that I would not want to be harmed or damaged it would have to be the Medulla and the Broca's area. Damage done to any parts of the brain can cause many effect to an individual. In my opinion, all parts of the brain are nessary and they each play a significant role that contributes to our lives and daily functions tramedously. Personally, I…

Introduction Motor neuron diseases (MND) are a group of pathologies in which motor neurons are selectively affected. Amyotrophic lateral Sclerosis (ALS) is a member of this group, affecting both upper (UMN) and lower motor neurons (LMN) [1]. ALS is a progressive neurodegenerative disease [1], with an estimated incidence in Caucasians of about 1,2-4,0 per 100,000 person-years [2]. ALS incidence increases with age, being more frequent between the 6th and 7th decades and in women more than men…