What are the two neurotransmitters released in the prefrontal cortex that stimulate receptors on postsynaptic neurons, allowing for optimal signal transmission and neuronal firing?

1. (Maureen) Three hypotheses influence the pathophysiology of schizophrenia. Serotonin, dopamine, GABA, and glutamate are the main chemicals involved in the three hypotheses of the development of schizophrenia (Singh et al., 2020). This discussion compares how the dopamine hypothesis and NMDA hypothesis are involved in the pathophysiology of schizophrenia. Besides, it highlights how the NMDA and dopamine hypotheses influence the development of both the positive and negative symptoms in schizophrenia.
Both NMDA and dopamine hypotheses play an essential role in the pathophysiology of schizophrenia. However, both follow different paths in their roles in the processes. Patients with schizophrenia can experience both positive and negative symptoms of the disease. The dopamine hypothesis has four different dopaminergic pathways that inform the development of schizophrenia (McCutcheon et al., 2020). The dopamine hypothesis contributes to a patient having positive symptoms of the disease. Besides, it also leads to excessive activation of the dopamine receptors through the mesolimbic pathways. The dopamine hypothesis affects the extrapyramidal system in situations where dopamine levels are low, especially in the nigrostriatal pathway. Besides, low levels of dopamine within the mesocortical pathway result in negative symptoms of schizophrenia.
On the other hand, NMDARs are forms of inotropic glutamate receptors made of NR1 and NR2/NR3 subunits. The subunits perform both pre and post-synaptic activities during the glutamatergic neurotransmission, synaptic plasticity, and local rhythmic activity (McCutcheon et al., 2020). The function of the N-methyl-d-aspartate receptor (NMDA) hypothesis in the development of schizophrenia is mainly understood by observing the functions of the NMDA receptor antagonists in the induction of the full range of the symptoms experienced by schizophrenic patients. McCutcheon et al. (2020) state that they are responsible for modulating high-order brain functions, memory, and cognition. NMDA plays a role in exacerbating the positive and negative symptoms of schizophrenia when there is a slowdown in its activity within the brain.
Questions
The following are positive symptoms of schizophrenia except:
Delusions
Hallucinations
Withdrawal
Movement disorders
Rationale- The answer is withdrawal. According to McCutcheon et al. (2020), understanding the negative and positive symptoms of schizophrenia is essential to know how they come about and how the different hypotheses contribute to the development of schizophrenia.
Which of the following chemical is not essential in the pathophysiologic pathways of the development of schizophrenia
Acetylcholine
Glutamate
Serotonin
Dopamine
Rationale- According to Singh et al. (2020), schizophrenia is a complex psychiatric disorder linked to different causes that need more profound understanding. Therefore, knowing and understanding the main neurochemicals involved in its pathophysiology makes it easier to understand how different neurochemical pathways are related to the development of schizophrenia.
2. (Toni) Historical the syndrome of hyperactivity, impulsivity, and inattentions was labeled attention-deficit disorder (ADD), “hyperactivity,” “hyperkinetic syndrome,” “minimal brain damage,” or “minimal brain dysfunction; however, these terms are no longer correct (Dulcan, 2017). Attention deficit hyperactivity disorder (ADHD) is well-known for a trio of symptoms: hyperactivity, impulsivity, and inattention. The hypothesis regarding the regulation of the brain and the impulsivity and inattention that is associated with ADHD is thought to arise for inefficient processing of information in the prefrontal cortex (PFC).
The PCF is located in the part of the brain at the front of the frontal lobe and contributes to a wide variety of executive functions. Executive functions include:
Coordinating and adjusting complex behaviors (“I can’t do A until B happens”)
Focusing one’s attention.
Impulse control; managing emotional reactions.
Planning for the future.
Predicting the consequences of one’s actions; anticipating events in the environment (Good Therapy, 2019).
Dulcan (2017) wrote that executive dysfunction is hypothetically linked to inefficient information processing in the dorsolateral prefrontal cortex (DLPFC). Dysfunction affecting the PLPFC is linked not only to ADHD but many other psychiatric disorders such as anxiety, disorders of sleep and wakefulness, major depression, mania, pain, and schizophrenia. Imbalances in norepinephrine (NE) and dopamine (DA) systems in the PCF, hypothetically occur in ADHD (Dulcan, 2017). It is hypnotized that increased levels of NE and DA would improve PFC function, thereby increasing stimulation of postsynaptic a2A receptors and stimulation of D1 receptors. Further theories about the role of NE is to increase incoming signals by allowing increased connectivity of the prefrontal networks, whereas the role of DA would be to decrease the noise by preventing inappropriate connections from taking place (Dulcan, 2017).
What are the two neurotransmitters released in the prefrontal cortex that stimulate receptors on postsynaptic neurons, allowing for optimal signal transmission and neuronal firing?
Dopamine and Acetylcholine
Acetylcholine and Norepinephrine
Dopamine and Norepinephrine
Acetylcholine and Serotonin
Answer: C, rational – Under normal conditions, norepinephrine and dopamine in the prefrontal cortex stimulate a few receptors on postsynaptic neurons, allowing for optimal signal transmission and neuronal firing (Dulcan, 2017, p. 455).
Deficient dopamine input will theoretically lead to ___________ noise, while deficient norepinephrine input will cause a __________ in the incoming signal.
Increased, decrease
Decreased, decrease
Increased, increase
Decreased, increase
Answer: A, rational – Deficient dopamine input will theoretically lead to increased noise, while deficient norepinephrine input will cause a decrease in the incoming signal (Dulcan, 2017, p. 455).