Related Experiment Video
Updated: Aug 16, 2026
12:21
Probing the Brain in Autism Using fMRI and Diffusion Tensor Imaging
Published on: September 12, 2011
The brain in infantile autism: posterior fossa structures are abnormal
E Courchesne1, J Townsend, O Saitoh
1Neurosciences Department, School of Medicine, University of California at San Diego, La Jolla.
Neurology
|February 1, 1994
Summary
Autism involves neurologic and developmental issues. This study found infantile autism samples include both cerebellar hypoplasia and hyperplasia subtypes, explaining previous MRI findings.
Area of Science:
- Neuroscience
- Developmental Biology
- Genetics
Background:
- Infantile autism is a neurologic disorder affecting social, cognitive, and language development.
- Previous studies indicated cerebellar hypoplasia in autistic patients, but recent findings suggest a hyperplasia subtype also exists.
- The presence of both hypoplasia and hyperplasia subtypes could explain discrepancies in prior MRI studies.
Purpose of the Study:
- To statistically reanalyze previous vermal area measures from autistic patients to test the hypothesis that samples comprise both hypoplasia and hyperplasia subtypes.
- To investigate the potential impact of these opposing subtypes on reported mean cerebellar sizes in autism research.
Main Methods:
- Statistical reanalysis of published vermal area measurements from 78 autistic patients across four independent studies.
- Examination of the distribution of hypoplasia and hyperplasia subtypes within these autistic samples.
Main Results:
- The reanalysis confirmed that the autistic patient samples were composed of both hypoplasia (ranging from 84% to 92%) and hyperplasia (ranging from 8% to 16%) subtypes.
- These findings align with a total of 226 autistic cases across 15 autopsy and MRI reports from nine laboratories.
Conclusions:
- Autism exhibits significant concordance across independent studies regarding the location and type of neuroanatomic maldevelopment, particularly in the cerebellum.
- Cerebellar maldevelopment may originate as early as the second trimester, and understanding its etiology is crucial for uncovering autism's causes.
More Related Videos
Related Concept Videos
01:14Cranial Bones: Superior and Posterior View
The superior view of the cranium shows the frontal and paired parietal bones.
The frontal bone is the single bone that forms the forehead. At its anterior midline, between the eyebrows, there is a slight depression called the glabella. The frontal bone also forms the supraorbital margin of the orbit. Near the middle of this margin is the supraorbital foramen, the opening that provides passage for a sensory nerve to the forehead. The frontal bone is thickened just above each supraorbital margin,...
The frontal bone is the single bone that forms the forehead. At its anterior midline, between the eyebrows, there is a slight depression called the glabella. The frontal bone also forms the supraorbital margin of the orbit. Near the middle of this margin is the supraorbital foramen, the opening that provides passage for a sensory nerve to the forehead. The frontal bone is thickened just above each supraorbital margin,...
01:18Anatomy of the Brain: Ventricles
There are hollow fluid-filled cavities known as ventricles deep inside the human brain. There are two lateral ventricles, one in each cerebral hemisphere, and each has three different projections — the anterior, inferior, and posterior horns visible from the lateral side. A thin membrane called the septum pellucidum separates the two lateral ventricles. The slender third ventricle in the diencephalon is connected to each lateral ventricle via a channel called the interventricular foramen. The...
01:26Cerebrum: Anatomical Overview I
The main and largest component of the human brain is the cerebrum. The cerebrum consists of two main parts: the cerebral cortex, an outer layer with wrinkles or folds known as gyri and shallow grooves called sulci, and a deeper region beneath it. The cerebrum divides into two distinct hemispheres and contains five different lobes: the frontal, parietal, temporal, occipital, and insula. The central sulcus separates the frontal and parietal lobes and two functionally important gyri — the...
01:21Association Areas of the Cortex
Association areas are regions of the cerebral cortex that do not have a specific sensory or motor function. Instead, they integrate and interpret information from various sources to enable higher cognitive processes such as memory, learning, and decision-making. Some key association areas include the following:
Prefrontal Association Area: This area is located in the frontal lobe and is involved in planning, decision-making, and moderating social behavior. It connects with primary motor areas,...
Prefrontal Association Area: This area is located in the frontal lobe and is involved in planning, decision-making, and moderating social behavior. It connects with primary motor areas,...
01:19Autism Spectrum Disorder
Autism spectrum disorder (ASD) is a neurodevelopmental condition marked by persistent deficits in social communication and interaction alongside restrictive and repetitive behaviors or interests. ASD is sometimes accompanied by intellectual impairment.
These core symptoms manifest differently among individuals, ranging from mild to severe. The disorder's complexity extends beyond its clinical presentation, encompassing a diverse range of biological, cognitive, and sociocultural influences.
These core symptoms manifest differently among individuals, ranging from mild to severe. The disorder's complexity extends beyond its clinical presentation, encompassing a diverse range of biological, cognitive, and sociocultural influences.
01:26Brain Abscess l: Introduction
A brain abscess is a focal, intracerebral infection characterized by a localized collection of pus within the brain parenchyma, resulting from microbial invasion and the body’s inflammatory response. It progresses through stages: early and late cerebritis, followed by early and late capsule formation, reflecting tissue destruction, immune response, and eventual encapsulation.Etiology and PathogenesisCausative organisms vary with source and host factors, often involving polymicrobial infections,...