Neuroscience has to do with the scientific study of the nervous system, including the brain. Neuroscience analyses the brain’s composition and the broader nervous system, including its biological and chemical processes. Behavioral genetics is the study of the relative effects of heredity and the environment on behavior and organisms’ mental processes. There are two theories as regards the origin of behavioral genetics. The view of nature maintains that hereditary factors and genes influence who we are, including our personality characteristics and physical appearance. On the other hand, nurture has to do with the fact that all the environmental variables impact us, including aspects such as our upbringing, our childhood experiences, our surrounding culture, and our social relationships. Human beings inherit 23 chromosomes from each parent, and each chromosome contains thousands of genes.
Heredity is one of the methods of studying inheritance among human beings. Human heredity can be understood more by engaging in studies including family studies, twin studies, adoption studies, and genetic abnormalities. Heredity is a statistical formula that shows a variation in percentage in a population attributed to genetic factors instead of the differences in the environment.
There are various misconceptions about genetics that exist. The first misconception is that genetic traits are inflexible; hence they cannot be fixed, which is not true. Environmental factors and lifestyle have the ability to determine if genes will be expressed or not. Additionally, the other misconception is that estimates of heredity only apply to groups and not individuals. In the real sense, estimates only apply to populations and not individuals. Another misconception is that gene and the environment and inseparable. The truth is that it is impossible to separate the influences of the environment and genes because the two affect each other.
Neurons, also known as nerve cells are the basic building blocks of the nervous system and are responsible for processing, receiving, and transmitting electrochemical information. The glial cells are responsible for providing nutritional, structural, and other support for neurons and communicating with the nervous system. The main parts of a neuron are the axon, cell body and dendrites. The dendrite is the fibrous root that branches out of the cell body. They receive and process signals coming from axons of other neurons. The cell body is the core of the neuron. It carries information, provided energy for activities, and maintains the structure of the neuron, Axon is a tail-like long structure that connects the cell body at the junction called the axon hillock. Axons are insulated with fatty substances called myelin. Myelin help axons conduct electrical signals. Terminal buttons are found towards the end of the neuron, and their function is to send alerts to other neurons. Neural communication is an electrochemical event made possible by various specialized structures in the neuron such as axons, dendrites, terminal buttons, and synaptic vesicles.
Neurotransmitters affect us in various ways. For instance, acetylcholine, which is found in acting drugs such as marijuana, nicotine, and amphetamines, is known for various effects such as rapid-eye movements, learning, muscle action, attention, and sleep motivation. Additionally, a decrease in acetylcholine plays a role in Alzheimer’s disease. Dopamine (DA) is a transmitter that is known for its effects on memory, movement, emotions and has been linked to Parkinson’s disease. On the other hand, endorphins affect memory, learning, mood, pain, appetite, and sexual activity. Epinephrine affects memory storage, energy release, and metabolism arousal. Serotonin affects moods, sleep, pain suppression, sleep, and appetite. Glutamate is known for its effects on movement, memory, and the nervous system. Drugs and poisons also affect our brains in various ways. Foreign chemicals such as drugs and poison can mimic and block ongoing actions of neurotransmitters, thus interfering with the body’s normal functioning.
The endocrine system is a network of glands found in the body which manufacture and secrete hormones and release them into the bloodstream. Hormones circulate in the bloodstream leading to bodily changes. The central nervous system comprises the spinal cord and the brain, while the peripheral nervous system entails all the neurons that are connected to the central nervous system. The brain has the ability to reorganize and change its structure through the formation of new neural connections. Reflexes of the spinal cord are produced by the central nervous systems’ pathways that lie entirely on the spinal cord. Sensory fibers evoke reflexes that enter the spinal cord activating spinal motor neurons directly or using a chain of spinal interneurons.
The brain is made up of three parts the hindbrain, forebrain, and midbrain. The hindbrain has the medulla, cerebellum, and pons. The medulla carries out automatic and vital functions such as heartbeat and respiration. Pons carries out movement, respiration, sleeping, waking, and dreaming. Cerebellum coordinates balance, muscle movement, perception, and cognition. The midbrain is a collection of structures responsible for coordinating sleep, movement patterns, and arousal. The forebrain comprises the thalamus, limbic system, cerebral cortex, and hypothalamus. The limbic system carries out primary physiological functions and is involved with memory and emotions. Hippocampus is involved in retrieving memories, while the hypothalamus governs sex drive and hormones. The amygdala controls emotions such as fear and aggression. Frontal lobes of the brain are responsible for speech production and motor control. Parietal lobes found at the top of the brain receive and interpret bodily sensations. Occipital lobes are responsible for vision. Temporal lobes are involved in audition and language comprehension. The Corpus callosum is responsible for conveying information between the two sections of the cerebral cortex.