The Neuropsychological Sequelae of Substance Abuse In Children, Adolescents, and Young Adults
(Ellen Krantz)
Following are some general conclusions about the neuropsychological findings related to the use of different
types of substances. From my brief review, most of the studies summarized have all sorts of methodological
problems particularly because, as is well-known, a good deal of individuals who use substances use more than
one and it is difficult to sort out the effects of one drug from another in individuals with polysubstance abuse.
With this in mind, here are a few major points:
Cocaine:
1. One of the most widely investigated drugs as well as one of the most widely abused illicit drugs in the United
States. High doses can create rapid motor activity, rambling speech, impaired judgment, paranoid and psychotic
behavior, irritability, and anxiety. EEG's show marked reduced Alpha power and frontal and temporal regions.
CT studies show evidence of cerebral atrophy and chronic users.
2. Newborn infants who were maternally exposed to cocaine were more likely to have reduced gestational age,
length, and head circumference. Some studies say cocaine exposure is associated with diminished birth weight,
and others do not. Often behavior or temperamental problems emerge by age 3. Cocaine exposed infants can
show increased tone and motor activity, more jerky movements, startles, tremors, back arching and signs of
central nervous system and visual stress. Some difficulties with auditory skills noted. Excitability and lethargy
were also observed. Heavily cocaine-exposed infants had more jitteriness and attentional problems and lightly
and non-exposed infants. Longitudinal studies with toddlers and preschoolers who were prenatally exposed
typically have low average to average cognitive abilities but tend to be highly distractible and can have
significant difficulties with speech and language development, peer interactions, and fine motor coordination.
3. Few longitudinal studies have been done. Barry et al., 1993 conducted one of the few longitudinal studies.
Young adults were studied initially within 72 hours of cocaine use and then two weeks later. The results
suggested that recent cocaine use resulted in specific neuropsychological impairment during the acute phase
including memory, visual-spatial deficits, and concentration problems. After two weeks of abstinence, this
group manifests similar deficits including psychomotor speed, memory, and concentration problems. These
deficits were consistent with deficits seen in dopamine depletion disorders such as Parkinson's and progressive
supranuclear palsy. Other studies have demonstrated deficits in planning and impulsivity.
Stimulants:
1. Stimulant toxicity may include repetitive teeth grinding, skin picking, perseverative speech or behavior,
preoccupation with one's own behavior and mental activity, suspiciousness, paranoia with auditory and
visual hallucinations, hyperactivity, confusion, convulsions, and even life-threatening condition such as
cardiovascular collapse and high fever progressing to death.
2. Withdrawal from stimulants can produce extreme depression, fatigue, extreme somnolence, and apathy.
Persistent mood and anxiety problems may last for several months.
3. Neuropsychological studies on the used of stimulants indicate they may damage the CNS and disrupt
memory, concentration, and abstract reasoning.
4. Exposure of infants to methamphetamines prenatally produces similar symptoms as are found in cocaine
exposed babies. These include lethargy, tremor, and increased intraventricular hemorrhage.
Heroin:
1. Associated with low birthweight, miscarriage, prematurity, microcephaly, and intrauterine growth
retardation.
THE FINE PRINT: Caveat emptor! These study materials have helped many people who have successfully completed the ABCN board certification
process, but there is no guarantee that they will work for you. The notes’ authors, web site host, and everyone else involved in the creation and
distribution of these study notes make no promises as to the complete accuracy of the material, and invite you to suggest changes.
Tobacco:
1. Associated with spontaneous abortions, premature rupture of membranes, preterm delivery, perinatal death,
low birth weight, and deficits in learning and behavior.
Alcohol:
1. A CNS depressant. Impairment in visual-motor skills, integration of sensory stimulation, and
information processing become apparent at blood levels of 100 mg (from the reading this seems to be
related to a feeling of intoxication). Higher blood levels eventually can result in sedation, CNS
depression, stupor, and even coma. Tolerance and physical and psychological dependence develop over
time with diagnosable alcoholism; this diagnosis can usually be made after three to 15 years of
prolonged use. Rarely do children or adolescents experience seizures, hallucinations, or the DT's which
are frequently experienced by adult users. Research done by Goldman, 1982 and Parsons, 1993 indicate
that older subjects show improvement after prolonged alcohol use but remain in the impaired range on a
variety of neurocognitive tests. This is not the same for younger individuals under the age of 35 to 40
who usually return to normal performance levels within about one month after they stopped drinking.
This is at least the finding in younger alcoholics who have use six years or less. After initial sobriety
alcohol dependence in younger adults (ages 18 through 35) have found few deficits in language skills,
attention, motor skills, intelligence, memory, and executive functions.
2. Neuroimaging studies have demonstrated that chronic alcoholism in older adults have produced
widespread rain damage but such evidence has not been apparent with children and younger adults.
3. The frontal lobes are uniquely sensitive to alcohol abuse although postmortem studies have implicated
temporal and parietal lobes as well. Clinical signs associated with damage to frontal cortex associated
with alcohol abuse include emotional apathy, disinhibition, poor attention, and abnormal perseverative
responding.
4. Drug abuse combined with heavy alcohol use, which is often typical, have resulted in MRI
examinations showing significantly smaller cerebellar vermes. Also more significant white matter
changes can occur.
Glue Sniffing
Neuropsychological deficits associated with glue sniffing include abnormalities in attention, memory, visualspatial functions, complex cognition, naming, and problems with reading or writing. Other studies have found
deficits in manual dexterity, visual scanning, and verbal memory. These deficits appear to be dose related.
Diffuse atrophy of cerebral hemispheres, cerebellum and in severe cases the brainstem were evident in 88.8% of
subjects studied. Importantly, this study was confounded because subjects evaluated also used amphetamines,
marijuana, and alcohol. Evidence of cognitive dysfunction and cerebellar, cortical spinal, and brains and signs
suggested a few CNS effects.
Marijuana
The research review I read was not particularly enlightening and complete, but the bottom line was that there is
a dose-response relationship with more heavy marijuana use resulting in greater deficits. Memory testing
appears to be the most significant cognitive area affected, and memory efficiency was noted as the primary
difficulty at least during active marijuana use.
Fletcher (1987) studied a group of long-term marijuana smokers who had used heavily for more than 30 years.
The findings indicated that these problems were noted on the test of sustained attention (a continuous
Performance test issues as a measure). Some short-term memory effects were also seen although these were
described as being very subtle or subclinical. In another study of younger adults, MRI studies showed evidence
of cerebral after a, including large left lateral ventricle, temporal lobe dilation, and damage to the caudate
nucleus and basal ganglia. These users had smoked for a period of three to 11 years. Once again were problems
in this study as most admitted to using other drugs.
THE FINE PRINT: Caveat emptor! These study materials have helped many people who have successfully completed the ABCN board certification
process, but there is no guarantee that they will work for you. The notes’ authors, web site host, and everyone else involved in the creation and
distribution of these study notes make no promises as to the complete accuracy of the material, and invite you to suggest changes.