Slow processing speed

Quick answer

Slow processing speed means your child takes longer than other children the same age to take in information, work with it, and give an answer back. It is a description of pace. It is not a diagnosis and it is not a disability category. Researchers define it as the efficiency with which a person understands and acts on what is in front of them, from the first look through the thinking to the speed of the answer.

Knowing the material and finishing on time are two different things.

On an evaluation report the number is called the Processing Speed Index.

What it looks like in a classroom

The pattern is the same in every room. Same work, more minutes. Or the same minutes and less finished.

• Answers correctly out loud, and hands in three of ten problems
• Copies half the board before the teacher wipes it
• Turns in a test with the first page right and the last page blank
• Homework planned for forty minutes runs two hours at the kitchen table

Teachers see the second version, because that is the one that lands on the desk. The word that comes back to parents is lazy, or careless, or unmotivated.

A 2015 study in the Journal of Learning Disabilities sorted 123 students aged 6 to 11 by learning disability subtype. The group whose weakness was processing speed showed the greatest psychosocial and adaptive impairment on teacher behavior ratings. The children who worked slowest were the ones their own teachers rated worst on behavior.

Slowness alone is not the school's problem. What matters is what the pace costs. A child who never reaches the last four problems never practices them, and that is instruction lost.

Where the number on the report comes from

The Wechsler Intelligence Scale for Children is the test most school psychologists reach for, and the score parents ask about is its Processing Speed Index, or PSI. Two subtests build it. Coding asks a child to match a symbol to a number from a key and copy it into a grid. Symbol Search asks whether a target symbol appears in a row. Both are timed and both run through a pencil.

Index scores are set so 100 is average and 15 points is one standard deviation, which puts a PSI of 85 below the middle. Subtests run on a scale averaging 10. A parent reading "PSI 82, Coding 6, Symbol Search 8" is reading a below-average pace on two paper tasks. That is all it is.

What the index cannot separate is thinking speed from hand speed. Researchers comparing Wechsler profiles in children with autism wrote that it is unclear whether a low index reflects cognitive processing speed, motor speed difficulties, or the two combined. Coding carries more handwriting demand than Symbol Search, so a gap between those two subtest scores is worth a question.

A low index also points nowhere by itself. It turns up across autism, attention deficit hyperactivity disorder, emotional and behavioral disorders, and several learning disability subtypes.

IDEA, the Individuals with Disabilities Education Act, says as much. A school cannot use any single measure as the sole criterion for deciding whether a child has a disability, at 34 C.F.R. § 300.304(b)(2), and it has to use a variety of assessment tools, at § 300.304(b)(1). That rule cuts both ways. It stops a district resting eligibility on one index, and it stops you proving your case with one.

Is slow processing speed a disability by itself?

No. IDEA names thirteen categories at 34 C.F.R. § 300.8(c) and processing speed is not one of them. A slow child reaches school services through one of three doors.

Specific learning disability is the most common route. The definition at § 300.8(c)(10)(i) is "a disorder in one or more of the basic psychological processes involved in understanding or in using language," and it may show up as trouble listening, thinking, speaking, reading, writing, spelling or doing math. Identification runs through § 300.309, which requires inadequate achievement in one of eight named areas and lets the group rely on "a pattern of strengths and weaknesses in performance, achievement, or both." That clause is where a slow index usually gets used. Read how dyslexia and other learning disabilities qualify for the way that evaluation runs.

Other health impairment is the second door, at § 300.8(c)(9). It turns on limited strength, vitality or alertness from a chronic or acute health problem that adversely affects educational performance, and the regulation names attention deficit hyperactivity disorder among its examples. See ADHD as an other health impairment.

Section 504 of the Rehabilitation Act is the third, and it has no categories. The test is a physical or mental impairment that substantially limits a major life activity, at 34 C.F.R. § 104.3(j), and the Office for Civil Rights lists learning, reading, concentrating and thinking among those activities. IEP vs 504 plan sets the two side by side.

None of the three turns on the number. Each turns on effect. A child can have a low index, a real slowdown at home, and still not qualify, because the pace does not cost enough at school to require special education. That answer is common and it is not always wrong.

What helps at school

Extended time is what a team offers first. It is also the accommodation with the least settled research behind it.

A 2010 review in Review of Educational Research called extended time one of the most common testing accommodations given to students with disabilities, and concluded the evidence raises concerns with the way it is currently provided. Critics say it changes what a test measures. Supporters say many students can only show what they know with it. A 2012 meta-analysis in the Journal of Learning Disabilities reported more questions than answers.

So ask for it, then ask the harder question. Where do the minutes come from. Time and a half on a 50-minute test is 25 extra minutes that have to exist inside a school day that does not have them, and a plan reading "extended time" and nothing else usually means your child keeps working while the next class starts. That is not extra time. That is a second subject taken away.

Four supports that do something the extra minutes do not.

• A copy of the notes or the slides, so the period is not spent copying
• A cut in the number of problems, written as a number, on the same skill at the same level
• Typing or speech to text where handwriting is the slow part
• Grading that separates work done wrong from work never reached

Testing accommodations get their own line in the IEP, at 34 C.F.R. § 300.320(a)(6)(i), and classroom supports belong in supplementary aids and services, at § 300.320(a)(4). Write the minute count, the room and the supervising adult into the plan, because an accommodation nobody scheduled is an accommodation nobody gives.

Extra time does not make a child faster. It pays for the pace out of a different account. Cutting the workload is a separate argument, because some teams call it an accommodation and some a modification, and the label follows a child into grades and diploma options. Accommodations vs modifications draws that line.

How to ask for an evaluation

You can start it. Either a parent or the district may request an initial evaluation, at 34 C.F.R. § 300.301(b). The district has to obtain your informed consent before it tests anything, at § 300.300(a)(1), and that same paragraph says consent for an initial evaluation is not consent for services. From the day it receives your consent the district has 60 days to complete the evaluation, or the timeframe your state set instead, at § 300.301(c)(1).

Put it in writing and date it. Bring counts, not adjectives.

If the answer is no, get the no in writing. Prior written notice is the document that makes a district explain a refusal and name the data behind it. For the longer version, see Requesting an evaluation.

Asking is not getting. An evaluation can come back not eligible, and a report saying the pace is fine has still moved the question somewhere useful.

Where an advocate fits

The argument here is about scheduling, not the score. An advocate reads the accommodation against the master schedule and asks which minutes your child actually gets, in which room, supervised by whom. Advocates are not attorneys. They cannot file a lawsuit or represent you at a due process hearing. Most advocates on our directory charge $75 to $150 per hour. Find advocates in your state.

What this page does not do

Four limits.

• This covers the school side of a slow pace and what you can ask a team for. It is not medical advice, it does not diagnose anything, and it does not tell you whether to see anyone about it.
• Slow processing speed is not an eligibility category, and a low Processing Speed Index does not qualify a child for an IEP by itself.
• The district's duty runs to educational effect. A pace that costs no instruction is not something a school must plan around.
• Testing accommodations and IEP forms are written by states and districts. Ask your district for its blank IEP form before you write anything.

The index tells you how long your child takes. The IEP has to say where the extra minutes come from.