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Updated: Jul 8, 2026
The Use of Trace Eyeblink Classical Conditioning to Assess Hippocampal Dysfunction in a Rat Model of Fetal Alcohol Spectrum Disorders
Published on: August 5, 2017
Impaired eyeblink conditioning in children with fetal alcohol syndrome
Sandra W Jacobson1, Mark E Stanton, Christopher D Molteno
1Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, Michigan 48207, USA. sandra.jacobson@wayne.edu
Insights
Children with Fetal Alcohol Syndrome (FAS) show impaired eyeblink conditioning (EBC), a learning deficit linked to prenatal alcohol exposure. This Pavlovian learning test may serve as a biomarker for FAS diagnosis, even without distinct facial features.
Area of Science:
- Neuroscience
- Developmental Psychology
- Public Health
Background:
- Eyeblink conditioning (EBC) is a Pavlovian paradigm used to study learning and memory.
- Animal studies indicate prenatal alcohol exposure impairs EBC, potentially due to cerebellar and brainstem neuronal loss and reduced plasticity.
Purpose of the Study:
- To investigate eyeblink conditioning (EBC) in children diagnosed with Fetal Alcohol Syndrome (FAS).
- To determine if EBC deficits are specific to prenatal alcohol exposure and could serve as a diagnostic biomarker.
Main Methods:
- A prospective longitudinal study involving 98 5-year-old children from Cape Town, South Africa.
- Fetal Alcohol Syndrome (FAS) diagnosis was confirmed by expert dysmorphologists.
- Short delay eyeblink conditioning (EBC) was assessed over multiple sessions.
Main Results:
- No children diagnosed with FAS met the conditioning criterion, compared to 75% of controls.
- Alcohol-exposed children without FAS showed delayed conditioning, requiring a third session.
- EBC deficits persisted even after controlling for IQ.
Conclusions:
- This is the first prospective study demonstrating impaired EBC in children with FAS.
- Impaired EBC appears specific to prenatal alcohol exposure, suggesting its potential as a biomarker for diagnosing children with FAS, especially those lacking typical dysmorphic features.
- Delayed EBC shows high sensitivity for identifying probable FAS cases.
Background:
Eyeblink conditioning (EBC) is a Pavlovian paradigm that involves contingent temporal pairing of a conditioned stimulus (e.g., tone) with an unconditioned stimulus (e.g., air puff). Animal studies have shown that binge consumption of alcohol during pregnancy impairs EBC and that this impairment is likely mediated by a loss of neurons in the inferior olive and the cerebellar cortex and deep nuclei, as well as by a reduction in neural plasticity in the cerebellar deep nuclei.
Methods:
Short delay EBC was examined in 98 5-year-old children born to women from the Coloured (mixed ancestry) community in Cape Town, South Africa, who were recruited prenatally and are participating in the first prospective longitudinal study of children with fetal alcohol syndrome (FAS). FAS status was assessed at 5 years by expert dysmorphologists. Two sessions of 50 trials each were administered to the children; a third session was administered the following day to those children who did not meet criterion of 40% conditioned responses in session 2.
Results:
Not a single child with FAS met criterion for conditioning as contrasted with 75.0% of the controls. Whereas 86.7% of the controls who were conditioned met criterion by the end of Session 2, a large proportion of the relatively few alcohol-exposed nonsyndromal children who conditioned did not do so until Session 3. These alcohol effects on EBC persisted after controlling for IQ. Three of 4 microcephalic children who were not exposed to alcohol were successfully conditioned.
Conclusions:
This is the first prospective study to demonstrate impaired EBC in children diagnosed with FAS. Successful EBC in a microcephalic group supports the inference that the EBC deficit is specific to prenatal alcohol exposure and a potential biomarker for diagnosis of exposed children lacking the distinctive FAS dysmorphology. Delay EBC has a high sensitivity for identifying individuals with a diagnosis of probable FAS.
