Comparing Amblyopia And Neuroplasticity
Most sensory systems have a limited critical period of development based on sensory input and high levels of plasticity. Is this the better way, or would it be better to have increased plasticity throughout life?
Daily encounters play an important role in shaping our neural circuits in the brain. The changes that occur as a result are called neuroplasticity. Neuroplasticity is not attributed to one type of change, but rather encompasses multiple processes which occur during a person’s lifetime. Neuroplasticity is most commonly observed in neurons and glia cells. During normal development, neuroplasticity is first evident when the brain starts processing sensory information through adulthood such as acquiring knowledge and motor development. Also neuroplasticity acts as a repairing mechanism to make up for lost function via brain damage. Moreover, the brain can be influenced by an individual 's environment and his/her daily interactions with other individuals. Although plasticity takes place throughout a human being’s lifetime, there are specific periods in a human’s life where plasticity is at its max and other periods of time where plasticity is less predominant. This is known as the critical period. It is basically a period in a lifetime when the organism is extremely sensitive to a certain stimulus important for a specific stage of development.
This article …show more content…
discusses the difference between the visual cortex critical period of dark reared and normal reared cats and mice. Authors have identified a gene called α-chimaerin that plays a crucial role in this critical period. The gene resides in the visual cortex of cats and mice. In cats, the critical period neuronal plasticity stays low until 3 postnatal weeks then peaks at 5 weeks and consequently declines till 20 weeks of age Eventually it disappears at the age of a year(Yang et al. 2011). Mice basically follow the same pattern but at a shorter course of time. Scientists found out that normal cats reared in the light showed increased plasticity at 5 weeks of age. However dark reared cats delayed the critical period such that increased plasticity occurred at 20 weeks of age. This discovery was influenced by the correlation between plasticity and α-chimaerin gene. The gene exhibited an increase in dark reared compared to normal reared animals at peak of normal critical period. Also an elevation was evident in light reared compared to dark reared at nadir of critical period (Yang et al. 2011). The results show that dark reared cats had reduced visual responsiveness and lower spontaneous activity than light reared ones. This illustrates why having a critical period at a specific time of an organism’s age is important.
In this article author’s showed an alternative treatment to amblyopia.
Amblyopia is also known as Lazy eye . Lazy eye is an early childhood condition where a child 's eyesight in one eye does not develop as it should. People with amblyopia were subjected to playing video games for a specific amount of time. Scientists found out that playing video games helped patients recover a substantial portion of their visual functions (Li et al. 2011). This discovery demonstrated that restoring normal eye function to certain degree is still possible even beyond the sensitive period of brain
development.
The two articles demonstrated two different but great aspects of the visual critical period. First article concluded, normal reared cats dominated dark reared ones despite the fact that both had a certain period of increased visual plasticity. This showed the consequences of the delayed critical period plasticity dark reared ones had and emphasized the period of time normal critical periods occur. However, the second article demonstrated a significant point about the notion of having an increased plasticity in which ,even having passed the critical period, playing video games helped restore a substantial amount of the visual functions people had before amblyopia. Personally, I think having increased plasticity throughout life would be better. As reported in the second article people with amblyopia were still able to recover some of the visual acuities (Li et al. 2011) which reflect a remarkable aspect of plasticity. In first article, it was mentioned that the critical period for dark reared cats was delayed, but that still didn’t give them any advantage. In fact it shows how trying to manipulate the critical period is bad having dark reared cats show reduced visual functions relative to light reared ones. However, the article was one sided and didn’t mention anything about some possible advantages of having such a delay.
References:
Yang, C, Zheng, Y, Kiser, P, Mower, G. 2011.Identification of α-Chimaerin as a Candidate Gene for Critical Period Neuronal Plasticity in Cat and Mouse Visual Cortex. BMC Neurosci 12:70.
Li, RW , Ngo, C , Nguyen, J, Levi, DM. 2011. Video-Game Play Induces Plasticity in the Visual System of Adults with Amblyopia. PLOS BIOLOGY 9(8): e1001135.
Daily encounters play an important role in shaping our neural circuits in the brain. The changes that occur as a result are called neuroplasticity. Neuroplasticity is not attributed to one type of change, but rather encompasses multiple processes which occur during a person’s lifetime. Neuroplasticity is most commonly observed in neurons and glia cells. During normal development, neuroplasticity is first evident when the brain starts processing sensory information through adulthood such as acquiring knowledge and motor development. Also neuroplasticity acts as a repairing mechanism to make up for lost function via brain damage. Moreover, the brain can be influenced by an individual 's environment and his/her daily interactions with other individuals. Although plasticity takes place throughout a human being’s lifetime, there are specific periods in a human’s life where plasticity is at its max and other periods of time where plasticity is less predominant. This is known as the critical period. It is basically a period in a lifetime when the organism is extremely sensitive to a certain stimulus important for a specific stage of development.
This article …show more content…
discusses the difference between the visual cortex critical period of dark reared and normal reared cats and mice. Authors have identified a gene called α-chimaerin that plays a crucial role in this critical period. The gene resides in the visual cortex of cats and mice. In cats, the critical period neuronal plasticity stays low until 3 postnatal weeks then peaks at 5 weeks and consequently declines till 20 weeks of age Eventually it disappears at the age of a year(Yang et al. 2011). Mice basically follow the same pattern but at a shorter course of time. Scientists found out that normal cats reared in the light showed increased plasticity at 5 weeks of age. However dark reared cats delayed the critical period such that increased plasticity occurred at 20 weeks of age. This discovery was influenced by the correlation between plasticity and α-chimaerin gene. The gene exhibited an increase in dark reared compared to normal reared animals at peak of normal critical period. Also an elevation was evident in light reared compared to dark reared at nadir of critical period (Yang et al. 2011). The results show that dark reared cats had reduced visual responsiveness and lower spontaneous activity than light reared ones. This illustrates why having a critical period at a specific time of an organism’s age is important.
In this article author’s showed an alternative treatment to amblyopia.
Amblyopia is also known as Lazy eye . Lazy eye is an early childhood condition where a child 's eyesight in one eye does not develop as it should. People with amblyopia were subjected to playing video games for a specific amount of time. Scientists found out that playing video games helped patients recover a substantial portion of their visual functions (Li et al. 2011). This discovery demonstrated that restoring normal eye function to certain degree is still possible even beyond the sensitive period of brain
development.
The two articles demonstrated two different but great aspects of the visual critical period. First article concluded, normal reared cats dominated dark reared ones despite the fact that both had a certain period of increased visual plasticity. This showed the consequences of the delayed critical period plasticity dark reared ones had and emphasized the period of time normal critical periods occur. However, the second article demonstrated a significant point about the notion of having an increased plasticity in which ,even having passed the critical period, playing video games helped restore a substantial amount of the visual functions people had before amblyopia. Personally, I think having increased plasticity throughout life would be better. As reported in the second article people with amblyopia were still able to recover some of the visual acuities (Li et al. 2011) which reflect a remarkable aspect of plasticity. In first article, it was mentioned that the critical period for dark reared cats was delayed, but that still didn’t give them any advantage. In fact it shows how trying to manipulate the critical period is bad having dark reared cats show reduced visual functions relative to light reared ones. However, the article was one sided and didn’t mention anything about some possible advantages of having such a delay.
References:
Yang, C, Zheng, Y, Kiser, P, Mower, G. 2011.Identification of α-Chimaerin as a Candidate Gene for Critical Period Neuronal Plasticity in Cat and Mouse Visual Cortex. BMC Neurosci 12:70.
Li, RW , Ngo, C , Nguyen, J, Levi, DM. 2011. Video-Game Play Induces Plasticity in the Visual System of Adults with Amblyopia. PLOS BIOLOGY 9(8): e1001135.