Psychology: Brain and Nervous System
Neural communication, brain structures, and behavior
Psychology: Brain and Nervous System
Neural communication, brain structures, and behavior
Psychology - Grade advanced
- 1
Explain how an action potential is generated and transmitted along an axon. Include resting potential, depolarization, repolarization, and the all-or-none principle in your explanation.
Focus on ion movement across the neuron membrane.
An action potential begins when a neuron at resting potential receives enough excitatory input to reach threshold. Sodium ions enter the axon and cause depolarization, then potassium ions leave and cause repolarization. The signal travels down the axon without losing strength because action potentials follow the all-or-none principle. - 2
Compare the roles of dendrites, the soma, the axon, and axon terminals in neural communication.
Dendrites receive signals from other neurons, and the soma integrates those incoming signals. The axon carries the electrical impulse away from the soma, and the axon terminals release neurotransmitters into the synapse to communicate with the next cell. - 3
Describe the process of synaptic transmission from the arrival of an action potential at the axon terminal to the effect on the postsynaptic neuron.
Include what happens before, during, and after neurotransmitter binding.
When an action potential reaches the axon terminal, vesicles release neurotransmitters into the synaptic cleft. The neurotransmitters bind to receptors on the postsynaptic neuron, causing either excitatory or inhibitory effects. The neurotransmitters are then cleared by reuptake, enzymatic breakdown, or diffusion. - 4
A medication blocks dopamine reuptake in the synapse. Predict how this medication would affect dopamine signaling and explain one possible behavioral effect.
Reuptake normally removes neurotransmitter from the synapse.
Blocking dopamine reuptake would leave more dopamine available in the synaptic cleft for a longer time, increasing dopamine signaling. A possible behavioral effect could be increased motivation, reward sensitivity, alertness, or risk for addictive patterns depending on the brain region affected. - 5
Distinguish between the central nervous system and the peripheral nervous system. Give one example of a structure in each system.
The central nervous system includes the brain and spinal cord and processes information. The peripheral nervous system includes nerves outside the brain and spinal cord and carries signals between the central nervous system and the body. The brain is part of the central nervous system, and spinal nerves are part of the peripheral nervous system. - 6
Compare the sympathetic and parasympathetic divisions of the autonomic nervous system. Use a stressful event and a recovery period as examples.
Think of activation first, then calming afterward.
The sympathetic division prepares the body for action during stress by increasing heart rate, widening airways, and redirecting energy for fight or flight. The parasympathetic division supports recovery by slowing heart rate, promoting digestion, and returning the body toward a resting state. - 7
A person touches a hot stove and pulls their hand away before consciously feeling pain. Explain how a spinal reflex can occur without initial conscious processing by the brain.
Sensory neurons carry the heat signal to the spinal cord, where interneurons activate motor neurons that quickly move the hand away. This reflex pathway can occur before the brain fully processes the pain, allowing a faster protective response. - 8
Explain how the thalamus and sensory cortex work together during perception. Include one exception to thalamic relay in your answer.
The thalamus is often described as a sensory relay station.
The thalamus relays most sensory information to the appropriate areas of the sensory cortex, where the brain interprets features such as touch, sound, and visual input. Smell is a major exception because olfactory information reaches other brain areas before being routed through the thalamus. - 9
Identify the primary functions of the frontal lobe, parietal lobe, temporal lobe, and occipital lobe.
The frontal lobe is involved in planning, decision making, voluntary movement, and impulse control. The parietal lobe processes touch and spatial information. The temporal lobe is important for hearing, language comprehension, and memory. The occipital lobe processes visual information. - 10
A patient has difficulty producing fluent speech but can understand spoken language fairly well. Which brain area is likely affected, and why?
Separate language production from language comprehension.
Broca's area is likely affected because it is important for speech production and fluent expressive language. Damage to this area often causes effortful or nonfluent speech while comprehension may remain relatively stronger. - 11
A patient speaks fluently but uses words that do not make sense and has difficulty understanding others. Which brain area is likely affected, and why?
Wernicke's area is likely affected because it is important for language comprehension and meaningful speech. Damage to this area can produce fluent but disorganized speech and poor understanding of spoken language. - 12
Explain how the hippocampus, amygdala, and prefrontal cortex may interact when a person forms a vivid memory of a frightening event.
Connect memory, emotion, and regulation.
The hippocampus helps form and organize the memory of the event and its context. The amygdala processes emotional significance and can strengthen memory for fear-related details. The prefrontal cortex helps evaluate the situation, regulate emotional responses, and later interpret the memory. - 13
Describe the role of the cerebellum in behavior. Include both motor and cognitive contributions.
The cerebellum coordinates balance, timing, posture, and smooth voluntary movement. It also contributes to learning motor skills and may support some cognitive processes such as attention, prediction, and sequencing. - 14
Compare an MRI scan, an fMRI scan, and an EEG. Explain one strength of each method for studying the brain.
Separate structure, blood-flow-based activity, and electrical timing.
An MRI provides detailed images of brain structure and is useful for identifying anatomy or damage. An fMRI measures changes related to blood flow and is useful for studying which brain areas are active during tasks. An EEG records electrical activity at the scalp and is useful for measuring rapid changes in brain activity over time. - 15
A teenager has damage to the prefrontal cortex after a head injury. Predict two changes in behavior or cognition that might occur and explain why.
The teenager might show poorer impulse control, weaker planning, reduced attention, or difficulty weighing consequences because the prefrontal cortex supports executive functions. These changes could affect decision making, emotional regulation, and goal-directed behavior.