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development of an animal model for attention deficit hyperactivity disorder: Effects of frontal lesions on activity in neonatal rats
Title
The development of an animal model for attention deficit hyperactivity disorder: Effects of frontal lesions on activity in neonatal rats.
Creator
Stevenson, Bernadette Mietus, Florida Atlantic University, Johanson, Ingrid B., Terry, Leslie M.
Abstract/Description
This study was designed to develop an animal model of Attention Deficit Hyperactivity Disorder based on frontal cortical functioning in 3, 6, 9, & 12-day-old neonatal rats. In Expt. 1, frontal cortical activity was suppressed with intracranial injections of lidocaine, a local anesthetic. In Expt. 2, frontal activity was suppressed with brain transections. Pups in both experiments were tested in a habituation-to-odor learning paradigm and behaviors including general activity, headwaving,...
Show moreThis study was designed to develop an animal model of Attention Deficit Hyperactivity Disorder based on frontal cortical functioning in 3, 6, 9, & 12-day-old neonatal rats. In Expt. 1, frontal cortical activity was suppressed with intracranial injections of lidocaine, a local anesthetic. In Expt. 2, frontal activity was suppressed with brain transections. Pups in both experiments were tested in a habituation-to-odor learning paradigm and behaviors including general activity, headwaving, probing, and rolling were recorded. Results indicated that frontal cortical suppression, caused by either lidocaine injection or brain transection, resulted in significantly higher activity levels in 3-day-olds particularly with regard to rolling, suggesting that the frontal cortex is involved in the regulation of rolling behavior. Frontal transections, but not lidocaine injections, also significantly increased activity in 12-day-old pups due to increased locomotor probing and wall climbing. Results are consistent with the neuropsychological research regarding frontal cortical functioning and inhibition in children with ADHD, and show potential as a future animal model of ADHD.
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Date Issued
1997
PURL
http://purl.flvc.org/fcla/dt/15516
Subject Headings
Attention-deficit hyperactivity disorder, Attention-deficit hyperactivity disorder--Diagnosis
Format
Document (PDF)
Structure and function in the developing brain: Effects of early frontal and cerebellar lesions on activity, learning, social and emotional behavior in the rat
Title
Structure and function in the developing brain: Effects of early frontal and cerebellar lesions on activity, learning, social and emotional behavior in the rat.
Creator
Stevenson, Bernadette Mietus, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Psychology
Abstract/Description
Autism, characterized by disrupted social interaction and communication skills, and Attention Deficit Hyperactivity Disorder (ADHD), characterized by hyperactivity and inattention, are two neurodevelopmental disorders that have recently been linked to common dysfunctions in the frontal lobes and cerebellum. The present study was designed to evaluate the neonatal rat as an animal model for neurodevelopmental disorders. The behavior of rats with early Frontal (FR), Cerebellar (CB), or Frontal +...
Show moreAutism, characterized by disrupted social interaction and communication skills, and Attention Deficit Hyperactivity Disorder (ADHD), characterized by hyperactivity and inattention, are two neurodevelopmental disorders that have recently been linked to common dysfunctions in the frontal lobes and cerebellum. The present study was designed to evaluate the neonatal rat as an animal model for neurodevelopmental disorders. The behavior of rats with early Frontal (FR), Cerebellar (CB), or Frontal + Cerebellar (FR + CB) lesions, performed at either Post-natal Day 2 (PD 2) or 9 (PD 9), was evaluated with regard to activity, learning, social, and emotional behavior between the age of 3--31 days. In Experiment 1, 3 and 10-day-old pups were tested on their ability to habituate to a novel odor. FR lesions increased activity in 3-days-olds while CB, and FR + CB lesions disrupted odor habituation learning in 10-day-olds. In Experiment 2, 17-day-old pups were evaluated on activity in the open-field and ability to habituate to a novel environment. FR lesions resulted in increased locomotor activity while CB lesions resulted in increased grooming, a stereotypical behavior. Pups with PD 9 CB lesions also failed to habituate to the novel environment of the open-field. In Experiment 3, 24-day-old juveniles were evaluated on social behavior in the play test, as measured by frequency of pinning behavior. FR lesions increased levels of play behavior while CB lesions decreased play. In Experiment 4, 31-day-old juveniles were evaluated on emotionality in the elevated plus maze as measured by the number of distal open arms entries. Rats with CB lesions made twice as many distal open arm entries relative to the other lesioned groups; however, this result did not reach statistical significance. In conclusion, the results of the present study suggest that the effects of early frontal and cerebellar lesions can be dissociated on several different behavioral measures in young rats. Furthermore, neonatal rats with frontal and cerebellar lesions exhibit several behaviors during ontogeny that mimic those seen in children with ADHD and autism, such as hyperactivity and disrupted social interaction. The neonatal rat may thus prove to be a useful animal model for childhood neurodevelopmental disorders.
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Date Issued
2001
PURL
http://purl.flvc.org/fcla/dt/11956
Subject Headings
Psychology, Psychobiology, Psychology, Developmental, Psychology, Physiological
Format
Document (PDF)