BIOLOGICAL PSYCHOLOGY

Biological Psychology

[Name of Student]

The biological basis of learning and memory

Question 1

Alteration of activity at GABAergic synapse

The inhibition at the GABAergic synapse plays a significant role as a regulator of excitation in the neural network. Theoretically, alteration can be made at the activity of GABAergic synapse through several ways. Firstly, GABA binds to two different types of receptor. These include ion channels and metabotropic receptors. The ion channels gated by GABA neurotransmitter are selectively permeable for ions, primary chloride and bicarbonate. The permeability of the ions can be altered and serve as the basis for several pharmacologically theories. Increasing the conductance at chloride or bicarbonate channels results in the activation of ionotropic GABA receptors. This leads to inhibition of the respective neuron, and ultimately a decreased generation of an action potential (Murphy, 2008).

Furthermore, at the GABA receptors, the neurotransmitter undergoes several mechanisms at molecular levels to achieve transporting, sequestration, synthesis, and its degradation. The GABA is transported across the cell membrane via the membrane-bound GABA transporters, which are NA+ coupled. Any effects in the electrochemican gradient of these transported can alter the packaging and transportation of GABA at the synaptic junction. The sequestration of GABA into small vesicles also uses the H+ electrochemical gradient, which holds pharmacological importance. Lastly, the strong activation of the axons increasing the extracellular concentration of GABA, also lead to increased availability of GABA for its release upon activation (Murphy, 2008).

It is observed that there are four ways in which activity at the GABAergic synapse could be altered and these ways are given as follows.

Autism Spectrum disorders.

Overexciting of Neurons.

Excessive muscle contraction.

Sense of restlessness.

These are the most significant ways in which the GABAergic synapse could be altered and these ways could definitely have negative effects in the brain and cause disorders in the memory system.

Difference between photoreceptors and ganglion cells

It has been analyzed that figure 1 has been adapted from figure 2.3 and potential membrane has been discovered both in the photoreceptors and the axon of the retinal ganglion cells. A similarity has been discovered from the analysis of the both the figures that a resting membrane potential was seen in the photoreceptors and the axon of the retinal ganglion cells. It is due to the identification of the resting membrane potential in both the figures that the adaption of figure 1 from figure 2.3 is affirmed.

The photoreceptors and ganglion cells are two different types of cells that function to form an image from the eye till the brain. Photoreceptors consist of rods and cones, which are activated only when light reaches it. The voltage-gated changes at the photoreceptors converge into bipolar cells. In contrast, the bipolar cells are known as retinal ganglion cells, and form the first cells of the visual pathway, which has an action potential. The retinal ganglion cells are activated when a threshold for action potential is reached (Murphy, 2008).

Cells containing GABA

In the figure, the inhibitory transmitter GABA should be present in the presynaptic, as well as, postsynaptic cell ...