Reaction-time lab
Safety gate · before any work
- Do not test reaction time in conditions that could cause injury (e.g., on a stairway or near equipment).
- The ruler-drop test should be conducted while seated to avoid falls if the subject lunges for the ruler.
- Do not use this lab to make medical claims about cognitive impairment.
Do now
Measure reaction time under different conditions and record the data.
- Hand in
- Reaction-time data table with baseline and distraction conditions, all trials with units, condition averages computed, and any outliers flagged with notes.
- Where
- Turn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not.
You get two school days for every day you were absent, so this deadline moves with you.
How many milliseconds does adding a distraction actually add to your , and can you measure it precisely enough to prove the difference is real and not just a lucky catch?
Measure under different conditions and record the data.
- • You can collect reaction-time data with units across conditions.
- • You can compute and compare condition averages.
- If two people catch a dropped ruler and one lets it fall farther before catching, whose was longer?
- Why would you run five trials per condition instead of just one?
- 1Set up the ruler-drop or digital reaction-time test and practice once.
- 2Run baseline trials and record each in a .
- 3Repeat trials with a distraction condition (such as a second task).
- 4Average each condition and note which was slower.
- 5Submit your reaction-time with both conditions and averages.
What did this day actually feel like?
Reaction-time lab
LAB Measuring our own reaction times, baseline against a distraction condition, multiple trials each.
My distraction numbers were dramatically worse and I genuinely did not feel slower while doing it. That gap between how it felt and what the stopwatch said is the most convincing argument about distracted driving anybody has ever made to me, and nobody made it, I measured it.
Turned in: reaction-time data table → Data Tables folder
Fiction. There is no such student. The lessons, labs and dates are the real planned course; the student, the classmates and the conversations are invented.
The same day, drawn.
Measuring our own reaction times, baseline against a distraction condition, multiple trials each.
Fiction. There is no such student. The lessons, labs and dates are the real planned course; the student, the classmates and the conversations are invented.
🛠 Get unstuck · pick your level
Lab day: Tier 1 is the whole class at the bench. No extension today.
🔑 Today's words · 5
Tap a word in the lesson for a plain meaning and one example. Recycled into next week's Do-Now.
Do the work · 80-minute blockfirst 5 min = hook▸
💡 Big idea: is a single measurable variable that reflects the whole pathway from to movement, so a consistent multi-trial protocol lets you prove that adding a distraction adds real, countable delay.
- 0-8Setup and one practice trial; establish consistent drop protocol
- 8-20Baseline condition: five trials, record time in ms or cm
- 20-35Distraction condition: five trials with secondary task, record
- 35-50Compute condition averages; flag outliers with notes
- 50-65Peer-check: units present in every row? Averages calculated correctly?
- 65-75Add qualitative observation column: describe how distraction felt
- 75-80Submit
- • Today you measure how fast your nervous system works. is the total time from to motor response.
- • We run two conditions: baseline and distracted. The distraction condition adds cognitive load, so the signal has to compete with other processing.
- • Record every trial with units. Compute the average for each condition. Mark any trial you consider an outlier and say why.
- • Your today feeds directly into Thursday analysis. Clean data now saves time Thursday.
- • Ruler-drop method converts distance (cm) to time (ms) using free-fall kinematics; digital tools measure time directly. Both require consistent protocol for valid comparison.
- • A distraction condition (dual-task) increases because it adds processing load on higher cortical areas, illustrating that conscious processing adds latency beyond the basic arc.
- • Computing a condition average requires recording at least five trials per condition and discarding obvious outliers (fumbled catch, early release).
Unit 2.1 Reflexes: Drug impacts on neuron signaling, reflex and reaction time, patient diagnosis challenge. · Reaction-time lab
Day 3 of this lesson. Open this exact section in myPLTW (find it in Clever, Microsoft sign-in), then do the work below.
Do this: Complete any lab-day check-in or data-entry prompt in Lesson 2.1 Getting Nervous on myPLTW that corresponds to today's reaction-time lab; log it alongside your in-class measurements.
Mark the lab task complete after submitting your reaction-time .
-arc task is done; today the lab task should show complete alongside your .
myPLTW completion status plus submitted .
The official PLTW activity stays inside myPLTW. If myPLTW will not open, use F1 and E1-E3 on this page to complete today's local evidence decision, then make up the official activity when access returns. Turn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not.
Check things off as you work, then submit. This tells Mr. Mendoza how you're doing so he can help the class. It does not replace turning in your producible through the submission route shown below.
Use the code Mr. Mendoza gave you, not your name. Saved on this device.
Unit 2.1 Reflexes: Drug impacts on neuron signaling, reflex and reaction time, patient diagnosis challenge. · Reaction-time lab
Complete any lab-day check-in or data-entry prompt in Lesson 2.1 Getting Nervous on myPLTW that corresponds to today's reaction-time lab; log it alongside your in-class measurements.
-arc task is done; today the lab task should show complete alongside your .
This is how Mr. Mendoza sees the class keeping pace with PLTW. Be honest, it only helps if it is accurate.
🎯 Measure under different conditions and record the data.
- Set up the ruler-drop or digital reaction-time test and practice once.
- Run baseline trials and record each in a .
- Repeat trials with a distraction condition (such as a second task).
- Average each condition and note which was slower.
- Submit your reaction-time with both conditions and averages.
Data table: Reaction-time with baseline and distraction conditions, all trials with units, condition averages computed, and any outliers flagged with notes.
Turn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not. Use the checklist just below and upload by 11:29 PM for full credit. Absent with an excused absence? You get two school days for every day you were absent, so this deadline moves with you.
| Task | Who |
|---|---|
| Set up the ruler-drop or digital reaction-time test and practice once. | _______ |
| Run baseline trials and record each in a . | _______ |
| Repeat trials with a distraction condition (such as a second task). | _______ |
| Average each condition and note which was slower. | _______ |
| Submit your reaction-time with both conditions and averages. | _______ |
Working solo? Put your own name in "Who" for every row.
- You can collect reaction-time data with units across conditions.
- You can compute and compare condition averages.
- 1Do thisMeasure reaction time under different conditions and record the data.
- 2Use this resource
- 3Submit thisData table: Reaction-time data table with baseline and distraction conditions, all trials with units, condition averages computed, and any outliers flagged with notes.
- 4Submit it here
- 1Open the drop folder.
- 2Sign in with your district Microsoft account, not a personal one.
- 3Upload the file, named Lastname_Firstname__Assignment Title.
- 4Your own upload panel says Uploaded with a green check: that is your receipt.
Turn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not. Human Anatomy & Physiology (Human Body Systems) › Unit 2.1 Reflexes: Drug impacts on neuron signaling, reflex and reaction time, patient diagnosis challenge. › Data tableOpen the drop folder
Learn it · deck, reading, and vocabulary▸
The deck carries the prior idea forward, lets you inspect an analogy, maps the rule to biology, and ends with the same evidence decision and exit ticket used on this page.
Generated from this lesson's canonical data with a red-team citation check.
Many legal medications slow neural signaling, so a driver can be genuinely impaired while breaking no drug law, which is why society has not settled how to assign blame.
is a single measurable variable that reflects the whole pathway from to movement, so a consistent multi-trial protocol lets you prove that adding a distraction adds real, countable delay.
A mechanic studies a tool whose shape allows one job but limits another.
- Which feature makes the tool work?
- What changes if that feature bends or breaks?
- Which observation shows function rather than appearance?
Structure creates possibilities and limits for function.
Living tissues adapt and interact with other systems; a metal tool does not.
- • Tool shape maps to .
- • The job maps to physiological function.
- • Damage maps to a predicted functional change.
Driving question: How many milliseconds does adding a distraction actually add to your , and can you measure it precisely enough to prove the difference is real and not just a lucky catch?
What you already know: Many legal medications slow neural signaling, so a driver can be genuinely impaired while breaking no drug law, which is why society has not settled how to assign blame.
New idea: is a single measurable variable that reflects the whole pathway from to movement, so a consistent multi-trial protocol lets you prove that adding a distraction adds real, countable delay.
Visual or model: F1. F1. A lesson illustration or teaching diagram for Reaction-time lab. Use it with E1-E3; it is a model or context image, not experimental or patient data. What to notice: Trace the labeled structure, movement, or system relationship that connects form to function.
- Observe or measure the relevant feature in Reaction-time lab.
- Organize the observation with a stable evidence ID.
- Apply this rule: Structure creates possibilities and limits for function.
- Choose the option the evidence supports and state the limit of the conclusion.
Real biomedical example: How many milliseconds does adding a distraction actually add to your , and can you measure it precisely enough to prove the difference is real and not just a lucky catch?
What the evidence supports: E1-E3 and F1 support the daily take-home when the response meets the stated success criteria.
What it cannot prove: The package does not support claims beyond this lesson's or any real patient diagnosis.
- • : A fast, automatic response to a that travels through the spinal cord, protecting the body before the brain consciously decides to act.
- • : The short interval between when a appears and when a person responds to it, reflecting how fast the nervous system processes signals.
- • : Any change in the environment, such as light, sound, or temperature, that a living thing can detect and respond to.
- • response: The body's reaction to a detected , carried out by muscles or glands to adjust to a change in the internal or external environment.
- • : A fatty insulating layer wrapped around nerve fibers that speeds up the electrical signals traveling along them.
- • : A , often on the cell surface, that binds a specific signal molecule and triggers a response inside the cell.
- • : The muscle, gland, or other part that carries out the body's response to a signal, acting on the command sent from a control center.
Use it now: Choose one decision option. Cite E1 and E3, then explain how the rule connects the evidence to your choice.
Go further, optional: The source links below are optional enrichment. Every fact required for today's local evidence decision appears in this lesson package.
Ruler-drop method converts distance (cm) to time (ms) using free-fall kinematics; digital tools measure time directly. Both require consistent protocol for valid comparison.
Limit: E1 supplies context or an observation; it does not by itself establish the explanation.
is a single measurable variable that reflects the whole pathway from to movement, so a consistent multi-trial protocol lets you prove that adding a distraction adds real, countable delay.
Limit: E2 is a teaching statement or comparison and must be checked against the task evidence.
You can collect reaction-time data with units across conditions.
Limit: E3 supports only the result or product criterion named here; it cannot justify a broader clinical or causal claim.
PLTW-HAP-2027-03-17 · Simulated classroom evidence scenario
Your role: anatomy and physiology consultant
Decision: Your team must decide what the evidence from Reaction-time lab supports before submitting the labeled and result claim named on the lesson page.
- • Proceed because the readiness evidence is complete.
- • Pause and correct the named setup or gap.
- • Repeat the measurement because quality controls are not acceptable.
Response: State one choice, cite at least two evidence IDs, explain the rule that connects them, and add one limitation. Submit it as the labeled and result claim.
Claim ceiling: The supplied lesson evidence can support an observation, pattern, classroom mechanism, or next-step decision about Reaction-time lab. It cannot by itself prove causation, establish a real clinical diagnosis, or justify action outside this classroom task.
- • The solution must address the stated need in Reaction-time lab.
- • The decision must be supported by E1-E3.
- • The final product must make the success criteria visible.
- • Complete the work inside the 80-minute block.
- • Use only supplied or teacher-approved materials and evidence.
- • Do not trade , accessibility, or privacy for speed.
- • and evidence quality: must pass before scoring other criteria.
- • User need and effectiveness: highest scored criterion.
- • Time, cost, and ease of use: compare only after and effectiveness pass.
Test evidence: For each option, record the E1-E3 result that supports or fails each criterion. Do not assign a score without a named observation.
- Version or option tested
- Criterion met or missed
- Evidence ID and result
- Revision made
- Reason for the revision
- Need and user
- Criteria and constraints
- Chosen option and evidence
- Test result
- Revision and reason
Students often think Students think one trial (or one great catch) is enough to know their .. The trap: It is a trap because a single trial mixes real with noise: a fumbled catch or an early release can swing the number wildly. You need at least five trials per condition and you discard obvious outliers, because only an average across repeated trials reflects your actual pathway speed.
Method: ruler-drop, distance converted to time in milliseconds. Five trials per condition.
Baseline condition (no distraction):
- Trial 1: 210 ms
- Trial 2: 195 ms
- Trial 3: 205 ms
- Trial 4: 380 ms (flagged outlier: fumbled catch, excluded)
- Trial 5: 200 ms
Baseline average (excluding outlier): 202.5 ms
Distraction condition (counting backward aloud):
- Trial 1: 265 ms
- Trial 2: 280 ms
- Trial 3: 255 ms
- Trial 4: 270 ms
- Trial 5: 260 ms
Distraction average: 266 ms
Which was slower: the distraction condition was slower by about 63.5 ms.
| Trial | Baseline (ms) | Distraction (ms) |
|---|---|---|
| 1 | 210 | 265 |
| 2 | 195 | 280 |
| 3 | 205 | 255 |
| 5 | 200 | 260 |
| Average | 202.5 | 266 |
This model shows the level of evidence and organization needed to complete: A reaction-time data table recording multiple trials in a baseline and a distraction condition with units, condition averages computed, and any outliers flagged with a note.
- Name the variables and include units.
- Enter observations without changing the raw values.
- Check labels, calculations, and patterns before interpreting the data.
Keep the structure. Replace the question, facts, measurements, and evidence. Then recheck units, vocabulary, and whether the conclusion goes beyond the evidence.
Also due today: Submit your completed data table.
- CER:
- Claim, Evidence, Reasoning: make a claim, back it with evidence, explain your reasoning.
- SOP:
- Standard Operating Procedure, the exact steps to follow (especially in a lab).
- Tracker:
- Your PLTW progress log where you record completed evidence.
- myPLTW:
- The PLTW course site where you do the online activities. Find it in Clever with your Microsoft sign-in, right next to Schoology.
Tap the speaker to hear a term. Add two of these to your notebook glossary with a definition and an example in your own words.
Pick just 2 or 3 words from today and make them yours: write what each one means in your own words, name the context clue or evidence that helped, then give one example from what you actually did in Reaction-time lab. Try your own words first; the glossary is there if you get stuck. This is voluntary and counts as extra credit, so keep it short.
Saved on this device. Show Mr. Mendoza or add these to your notebook glossary to claim the extra credit.
Hand-picked readings, videos, and interactives for this lesson, all free and from authoritative open organizations (NIH, CDC, OpenStax, Khan Academy, PhET, HHMI, and more).
A fillable, Cornell-style notebook for Unit 2: Research Ready. Type your notes, cues, and summaries right in the PDF, or print it and write by hand. Each lesson page has a cue column, a notes column, and a summary box, plus dated lab-record pages you can turn in.
HBS Unit 2 notebook: Research Ready Fillable PDFCornell notes + lab recordsOpenVetted readings and references for this unit. Use them to prepare, to catch up if you were absent, or to go deeper on today's target.
Check yourself · commit, then reveal▸
Claim ceiling for this check: The supplied lesson evidence can support an observation, pattern, classroom mechanism, or next-step decision about Reaction-time lab. It cannot by itself prove causation, establish a real clinical diagnosis, or justify action outside this classroom task.
Your baseline reaction time averages 220 ms. In the distraction (dual-task) condition your average is 290 ms. Which nervous-system idea explains the 70 ms increase?
Write an answer and pick a confidence to unlock the key.
Fast retrieval with instant answers, not the commit-then-reveal check above. Try each from memory first: write what you remember about the earlier units, then check yourself here.
Go further and get help▸
I can name the procedure's purpose and the evidence I will record. I can identify each named hazard and the control that reduces it: Do not test reaction time in conditions that could cause injury (e.g., on a stairway or near equipment). My data table is ready before materials are handled.
Finish the checklist before you handle any material.
- • Do not test reaction time in conditions that could cause injury (e.g., on a stairway or near equipment).
- • The ruler-drop test should be conducted while seated to avoid falls if the subject lunges for the ruler.
- • Do not use this lab to make medical claims about cognitive impairment.
- 1Before materials are handled, identify the purpose, variables or comparison, controls, measurement units, and stop-work condition.
- 2Set up the ruler-drop or digital reaction-time test and practice once.
- 3Run baseline trials and record each reaction time in a data table.
- 4Repeat trials with a distraction condition (such as a second task).
- 5Average each condition and note which was slower.
- 6Submit your reaction-time data table with both conditions and averages.
- 7Record each result in the prepared table before interpreting it. Mark missing, repeated, or invalid results truthfully.
- 8Complete the named cleanup and waste route, remove PPE safely, wash hands when required, and confirm the station is ready for the next group.
| Trial or sample ID | Independent condition | Measured result with units | Observation before interpretation | Quality-control note |
|---|---|---|---|---|
Before the procedure, predict the result and cite the rule behind the prediction.
After the procedure, compare the result with the prediction and name one limitation or source of uncertainty.
What today's skills lead to. These are real health-science careers this course builds toward. Tap one to see, on the US Department of Labor's O*NET site, what the job actually involves, what it pays, and how fast it is growing.
Use the linked simulation or the online ruler-drop method to record reaction-time trials in a baseline and a distraction condition, build a with averages, and submit it.
PhET SimulationsThen submit your Data table. Turn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not.
Class still runs. Complete the online activity above (it's self-guided). Need the concept taught without a teacher? Use this authoritative explainer:
Khan Academy: Neurons and Synapses- CompleteEvery required part of the artifact is present, nothing left blank.
- AccurateThe science and the data are correct and match the evidence.
- Scientific reasoningYou explain your claim with evidence and reasoning (CER), not just an answer.
- Professional communicationClear, organized, labeled, and written the way a clinician or scientist would.
- SubmittedTurned in the right way, on the class site or handed to Mr. Mendoza in class, and confirmed. Not in Schoology: that is where the report-card grade appears later.
- Error analysis and method · counts doubleName a specific limit of the method and how it moved your result, and compare what you predicted to what happened. "Human error" does not count; say what about the procedure or instrument caused it.