The term “learning disability” was apparently first used and defined by Kirk (1962, cited in Streissguth, Bookstein, Sampson, & Barr, 1993, p.144). The term referred to a discrepancy between a child’s apparent capacity to learn and his or her level of achievement. A review of the LD classifications for 49 of 50 states revealed that 28 of the states included IQ/Achievement discrepancy criteria in their LD guidelines (Ibid., citing Frankenberger & Harper, 1987). However, the National Joint Committee for Learning Disabilities (NJCLD)(1981; 1985) preferred a slightly different definition:
‘Learning disabilities’ is a generic term that refers to a heterogeneous group of disorders manifested by significant difficulties in the acquisition and use of listening, speaking, reading, writing, reasoning or mathematical abilities. These disorders are intrinsic to the individual and presumed to be due to central nervous system dysfunction. Even though a learning disability may occur concomitantly with other handicapping conditions (e.g., sensory impairment, mental retardation, social and emotional disturbance) or environmental influences (e.g., cultural differences, insufficient/inappropriate instruction, psychogenic factors), it is not the direct result of those conditions or influences. (quoted in Streissguth et al., 1993; see also NJCLD, 1985).
Thus there are two different views of LD: one that defines it in terms of a difference between IQ and achievement, and another that defines it as being below normal on both indices. A more recent definition of LD, by the Interagency Committee on Learning Disabilities (ICLD) (1989), does not mention IQ as a defining characteristic:
Learning
disabilities is a generic term that refers to a heterogeneous group of
disorders manifested by significant difficulties in the acquisition and use of
listening, speaking, reading, writing, reasoning, or mathematical abilities, or
of social skills. These disorders are intrinsic to the individual and presumed
to be due to central nervous system dysfunction. Even though a learning
disability may occur concomitantly with other handicapping conditions (e.g.,
sensory impairment, mental retardation, social and emotional disturbance), with
socioenvironmental influences (e.g., cultural differences, insufficient or
inappropriate instruction, psychogenic factors) and especially attention
deficit disorder, all of which may cause learning problems, a learning
disability is not the direct result of those conditions or influences.
The DSM-IV uses the term “Learning Disorder (formerly Academic Skills Disorders)”, that seems to follow the NJCLD definition:
Learning
Disorders are diagnosed when the individual’s achievement on individually
administered, standardized tests in reading, mathematics, or written expression
is substantially below that expected for age, schooling, and level of
intelligence. The learning problems significantly interfere with academic
achievement or activities of daily living that require reading, mathematical,
or writing skills. A variety of statistical approaches can be used to establish
that a discrepancy is significant. Substantially below is usually
defined as a discrepancy of more than 2 standard deviations between achievement
and IQ. A smaller discrepancy between achievement and IQ (i.e., between 1 and 2
standard deviations) is sometimes used, especially in cases where an
individual’s performance on an IQ test may have been compromised by an
associated disorder in cognitive processing, a comorbid mental disorder or a
general medical condition, or the individual’s ethnic or cultural background.
If a sensory deficit is present, the learning difficulties must be in excess of
those usually associated with the deficit. Learning Disorders may persist into
adulthood.
Demoralization,
low self-esteem, and deficits in social skills may be associated with Learning
Disorders…Adults with Learning Disorders may have significant difficulties with
employment or social adjustment. Many individuals (10%-25%) with Conduct
Disorder, Oppositional Defiant Disorder, Attention-Deficit/Hyperactivity
Disorder, Major Depressive Disorder, or Dysthymic Disorder also have Learning
Disorders…
There may be underlying abnormalities in cognitive processing (e.g., deficits in visual perception, linguistic processes, attention or memory, or a combination of these) that often precede or are associated with Learning Disorders. Standardized tests to measure these processes are generally less reliable and valid than other psychoeducational tests…Learning Disorders are…frequently found in association with a variety of general medical conditions (e.g., lead poisoning, fetal alcohol syndrome, or fragile X syndrome.) (DSM-IV pp.46-47.)
This approach to learning disabilities results in the definition of the following Learning Disorders:
· 315.00 Reading Disorder
· 315.1 Mathematics Disorder
· 315.2 Disorder of Written Expression
· 315.9 Learning Disorder Not Otherwise Specified
The last category might include problems in all three areas that together significantly interfere with academic achievement even though tests measuring each individual skill is not substantially below that expected given the person’s chronological age, measured intelligence, and age-appropriate education (DSM-IV, p.53).
Sometimes cultural or ethnic differences in learning patterns can be mistaken for a learning disorder, but the DSM-IV definition of learning disorders excludes this possibility, and a culturally competent diagnostician will not diagnose a learning disorder on this basis (DSM-IV, pp 47-48). All of these factors must be taken into account when making a diagnosis or providing treatment.
One other definition of importance is provided in the Individuals with Disabilities Education Act (IDEA). The federal government defines learning disabilities in Public Law 94-142, as amended by Public Law 101-76 (IDEA):
Specific learning disability
means a disorder in one or more of the basic psychological processes involved
in understanding or in using language, spoken or written, which may manifest
itself in an imperfect ability to listen, think, speak, read, write, spell, or
to do mathematical calculations. The term includes such conditions as
perceptual handicaps, brain injury, minimal brain dysfunction, dyslexia, and
developmental aphasia. The term does not include children who have problems
that are primarily the result of visual, hearing, or motor disabilities, or
mental retardation, emotional disturbance, or of environmental, cultural, or
economic disadvantage.
Although the definition in
federal law governs the identification of and services to children with
learning disabilities (LD), there are variations between states and among
school systems. In an attempt to clarify the identification, some states
specify an intelligence range. Others add a concept of a discrepancy between
potential and achievement, sometimes quantifying the discrepancy using test
scores. These slightly different "yardsticks" are indicative of a
lack of clear consensus about exactly what learning disabilities are.
Streissguth, et al. (1993, 145, 147-152) were able to show that prenatal exposure to alcohol statistically predicts the NJCLD type of LD, but not Kirk’s type of LD. According to Johnson (1999, p.22), other more anecdotal sources seem to distinguish the learning problems associated with FAS/ARND from those associated with LD (Burgess & Streissguth, 1992; Kleinfeld, 1993; Morse 1993), “presumably on the basis of the differing neurological etiologies of the learning problems.” Johnson (1999, pp.23f.) has developed a parallel list of learning problems in children with FAS/FAE and children with Learning Disabilities, shown below as Table 1. In general, the learning problems of children with FAS/ARND may be more intractable than in students with learning disabilities (shown in table by “*”). Differences in the table are highlighted in italics. The point here is that LD with FAS/ARND is not the same as LD without FAS/ARND, and that treatment strategies that work with the latter may not work with the former.
Table 1.
Learning problems in children with FAS/FAE and Learning Disabilities
|
Children with FAS/FAE |
Children with LD |
|
IQ range 20-130 |
IQ range same as normal
population |
|
*Problems with sound/symbol
relationships & phonological awareness |
Problems with sound/symbol
relationships & phonological awareness |
|
*Problems with storage and
retrieval of information |
Problems with storage and
retrieval of linguistic information |
|
May be slow to
process language |
|
|
*Problems with spelling,
reading, writing, and math |
Problems with spelling,
reading, writing, and sometimes math |
|
*Difficulty with abstract
relationships |
May have difficulty
with abstract relationships |
|
*May be able to decode but
struggle with comprehension |
May be able to decode but
struggle with comprehension |
|
*Poor cognitive processing, especially
executive and strategic processes |
May have poor
cognitive processing |
|
(Not known) |
May have reversals in
reading and writing |
|
*Impulsive; lack of awareness
of consequences |
May be impulsive;
may show lack of awareness of consequences |
|
*Problems organizing ideas,
things, time |
Problems organizing ideas,
things, time |
|
*Poor short and/or long term
memory |
Poor short and/or long term
memory |
|
*Poor sequencing, especially
instructions |
Poor sequencing, especially
instructions |
|
*Problems generalizing from one
activity or situation to another |
Problems generalizing from one
activity or situation to another |
|
*Transitions between activities
are often difficult, and may cause child to withdraw or be disruptive |
Transitions between activities may
be difficult |
|
*Poor communication skills,
especially pragmatics of language |
May have poor
communication skills, especially pragmatics of language |
|
*Variability; marked difference
between “good days” and “bad days” |
May show variability;
marked difference between “good days” and “bad days” |
|
*At risk for developing
secondary problems such as depression, anxiety, substance abuse, trouble
with the law |
Barbara Morse (1993, p.32) expresses learning disabilities in terms of information processing deficits:
Information
processing deficits were first defined in the 1960s to represent learning
disabilities in four domains: input, integration, memory, and output. Input
represents the recording of information from the senses. Memory represents the
storage of information for later use. Integration is the process of
interpreting the input. Output requires appropriate use of language and motor
skills. Many people have a learning disability in one or two areas; children
with FAS seem to have processing deficits in all areas.
The course of these disorders can be mild to severe. Some children with learning disorders or those with intensive, early, and appropriate interventions can make progress. For some people, these are permanent disorders affecting the person’s academic, vocational, and social functioning throughout their life. A school psychologist, clinical psychologist, psychiatrist, or other qualified specialist can make this diagnosis. If there is a head trauma or other medical problem (such as encephalitis), a physician should be on the diagnostic team (LaDue, n.d., 199).
· A study of 145 FAS/ARND cases in Alaska (Colberg, 1997) showed that 41% of the cases had speech or language delay, 28% had short attention span or attention deficit disorder (ADD), and 20% had learning disability or mental retardation. Most of these 145 cases (83%) were Alaska Natives. Multiple disabilities were common.
· In another study in Alaska of 36 children with FAS, 34% had a speech impairment, 20% had learning disabilities (Gessner, Bischoff, Perham-Hester, Chandler, & Middaugh, 1998).
According to Johnson (1999, 22), the literature seems to distinguish learning problems associated with FAS/FAE from those associated with LD (Burgess & Streissguth, 1992; Kleinfeld, 1993; Morse, 1993).
A somewhat more indirect measure of learning disabilities is “Disrupted school experience”(DSE), one of the “secondary disabilities” of FAS/FAE defined by Streissguth, Barr, Kogan & Bookstein (1996, p.37-41). Persons who ever were suspended from school, expelled from school, or dropped out of school were considered to have DSE. Among male teenagers, at least 70% had had DSE. Among female teenagers, 40% of those with FAS had DSE, compared with 50% of those with FAE. But among adults, the results by sex were reversed: More females than males had DSE. For both teenagers and adults, persons with “FAE” had more DSE (>70%) than persons with FAS (42% [males], 52% [females]). In this study, 40% of the clients with FAS/FAE were known to have been in special education, more than 60% had received remedial intervention for reading, more than 60% for arithmetic, about 45% for written language, and about 42% for speech problems.
Closely related to the Learning Disorders are the Communication Disorders, including
· 315.31 Expressive Language Disorder
· 315.31 Mixed Receptive-Expressive Language Disorder.
Codes for the two disorders are the same, but the DSM-IV distinguishes between their diagnostic features (DSM-IV pp. 55-60).