The Brain and Nerves Demonstrations

See also: Senses and Perception

Demonstrations on the brain and nerves reveal how signals travel through the nervous system to control thought and movement. These activities highlight the complexity of the body’s control center in a way that textbooks alone cannot.

Demonstration	Materials	Difficulty	Safety	Summary
Afterimage Illusion	★☆☆	★☆☆	★☆☆	Stare at a brightly colored image for a short time, then look at a blank white surface and observe a “ghost” image that appears in complementary colors. This activity demonstrates how cone cells adapt and how the opponent process in vision creates negative and positive afterimages.
Blind Spot	★☆☆	★☆☆	★★☆	Students use a simple card with a dot and an X to locate their blind spot. By covering one eye and moving the card at arm’s length, they observe how part of their vision disappears when light falls on the optic nerve instead of light-sensitive cells in the retina.
Blood Flow and Artery Constriction	★☆☆	★★☆	★☆☆	This demonstration models how artery size affects blood flow. Water dyed red to represent blood flows through tubes of different diameters, showing that narrower arteries restrict flow and increase resistance, similar to what happens in the human body when vessels are constricted.
Dropping Ruler Reaction Time	★☆☆	★☆☆	★☆☆	Students test their reaction speed by trying to catch a falling ruler as quickly as possible. The activity demonstrates how the nervous system processes information from the eyes to the brain and then to the muscles to produce a response.
Short-Term Memory	★☆☆	★☆☆	★☆☆	Participants try to memorize and recall a list of unrelated words within a short time frame, demonstrating the limits of short-term memory capacity. They then attempt a second list organized into categories, showing how chunking strategies can improve recall.
Simple and Choice Reaction Time Tasks	★☆☆	★☆☆	★☆☆	This demonstration compares simple reaction time (SRT) tasks, where there is one stimulus and one response, with choice reaction time (CRT) tasks, where multiple stimuli each require different responses. It shows how reaction time increases with task complexity, illustrating Hick’s law and the speed-accuracy trade-off.
Stroop Effect	★☆☆	★☆☆	★☆☆	The Stroop Effect is a demonstration of how conflicting information from reading and color recognition interferes with response time. When the name of a color is printed in a different color ink, people take longer to identify the ink color than to read the word itself.
The McGurk Effect	★☆☆	★☆☆	★☆☆	The McGurk effect occurs when conflicting visual and auditory cues lead the brain to misinterpret what sound is being heard. By combining mismatched audio and video of a spoken word, students can observe how visual information influences auditory perception.
The Spacing Effect	★☆☆	★☆☆	★☆☆	Students hear words presented twice either back to back (massed) or separated by other items (distributed), then attempt free recall. Class results typically show better recall for distributed items, illustrating the spacing effect and motivating distributed study habits.
Two Point Discrimination	★☆☆	★☆☆	★☆☆	Students test how well different areas of the body can distinguish between one and two points of touch using a simple two-point discrimination device. The activity demonstrates the uneven distribution of touch receptors across the skin and why some areas are more sensitive than others.
Visual and Auditory Reaction Time	★☆☆	★☆☆	★☆☆	Students measure and compare their visual and auditory reaction times by catching a falling meter stick, analyzing how quickly they respond to different types of stimuli. The experiment highlights how the nervous system detects, processes, and responds to environmental signals.
Learning Curves in Sports Skills	★★☆	★☆☆	★☆☆	Students practice a simple sport-related skill in repeated blocks and quantify performance over time to reveal a learning curve (better accuracy, faster times, reduced variability).
Learning New Skills Mirror Maze	★★☆	★☆☆	★☆☆	In this activity, participants trace a star shape while only viewing their hand’s reflection in a mirror. The task is repeated across multiple trials and days, demonstrating motor learning, memory, and adaptation as performance improves over time.
Sheep Brain Dissection	★★★	★★☆	★★☆	Students examine a sheep brain to identify major external and internal structures. The activity includes removing the dura mater, separating hemispheres along the longitudinal fissure, and locating key features such as the corpus callosum, ventricles, colliculi, pineal gland, cerebellar arbor vitae, gyri, and sulci.

Materials
★☆☆ Easy to get from supermarket or hardware store
★★☆ Available in most school laboratories or specialist stores
★★★ Requires materials not commonly found in school laboratories

Difficulty
★☆☆ Can be easily done by most teenagers
★★☆ Available in most school laboratories or specialist stores
★★★ Requires a more experienced teacher

Safety
★☆☆ Minimal safety procedures required
★★☆ Some safety precautions required to perform safely
★★★ Only to be attempted with adequate safety procedures and trained staff