Related Experiment Video
Updated: Feb 7, 2026

A Wireless, Bidirectional Interface for In Vivo Recording and Stimulation of Neural Activity in Freely Behaving Rats
Published on: November 7, 2017
Caudate nucleus neurons participate in methylphenidate function: Behavioral and neuronal recordings from freely
Tahseen J Karim1, Ceren Aksel1, Natasha Kharas1
1McGovern Medical School, 6431 Fannin Street, Houston, TX 77030, United States.
Abstract:
Methylphenidate (MPD) is the most commonly prescribed psychostimulant for the treatment of attention-deficit hyperactivity disorder (ADHD). MPD acts on brain structures of the reward/motivation system, including the caudate nucleus (CN). The objective of this study was to investigate the acute and chronic dose response effects of MPD on CN neurons in freely behaving adolescent rats. Semi-microelectrodes were implanted into the CN of one hundred and sixty-three adolescent male Sprague-Dawley rats. On experimental day one (ED1), each rat was injected with 0.8 ml saline followed by an injection of MPD (0.6, 2.5, or 10.0 mg/kg). Behavioral and neuronal recordings of 60 min followed each injection. Throughout ED2-6, each rat remained in its home cage and received daily injections of a specific dose of MPD. ED7-9 consisted of a three-day washout period during which no injections were given. On the last day (ED10), each rat was returned to the testing chamber in its home cage and an identical protocol was performed as on ED1. The same repetitive (i.e. chronic) dose of MPD elicited behavioral sensitization in some animals and behavioral tolerance in others. After chronic MPD exposure, CN units recorded from rats expressing behavioral sensitization responded mainly with increased neuronal firing rates. Conversely, rats expressing behavioral tolerance responded mainly with decreased neuronal firing rates. These findings suggest a direct correlation between the behavioral and CN neurophysiological response to chronic MPD in adolescent animals.
Related Concept Videos
The Nucleus
Arrangement of DNA within Nucleus
The regulation of gene expression inside the nucleus is dependent on many factors, including the DNA structure. The...
The Nucleus
Arrangement of DNA within Nucleus
The regulation of gene expression inside the nucleus is dependent on many factors, including the DNA structure. The...
Neurons: The Axon
The axon attaches to the cell body at a cone-shaped elevation called the axon hillock. The initial part of the axon, closest to the hillock, is known as the initial segment....
Neuron Structure
Neuron Structure
Structure and Function of Neurons
The neuronal cell body—the soma— houses the nucleus and organelles vital to...
Neuronal Communication

