Focal stimulation of the thalamic reticular nucleus induces focal gamma waves in cortex.
Electrical stimulation of the thalamic reticular nucleus (TRN; 0.5-s trains of 500-Hz 0.5-ms pulses at 5-10 microA) evokes focal oscillations of cortical electrical potentials in the gamma frequency band ( approximately 35-55 Hz). These evoked oscillations are specific to either the somatosensory or auditory cortex and to subregions of the cortical receptotopic map, depending on what part of the TRN is stimulated. Focal stimulation of the internal capsule, however, evokes focal slow potentials, without gamma activity. Our results suggest that the TRN's role extends beyond that of general cortical arousal to include specific modality and submodality activation of the forebrain.
Macdonald
K D
KD
Department of Psychology, University of Colorado at Boulder, Boulder, Colorado 80309-0345, USA.
Fifkova
E
E
Jones
M S
MS
Barth
D S
DS
D000161:Acoustic Stimulation; D000818:Animals; D001303:Auditory Cortex / Q000502:physiology*; D001370:Axonal Transport; D001931:Brain Mapping; D005072:Evoked Potentials, Auditory; D005073:Evoked Potentials, Somatosensory; D005552:Forelimb / Q000294:innervation; D007839:Functional Laterality; D009991:Oscillometry; D010812:Physical Stimulation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013003:Somatosensory Cortex / Q000502:physiology*; D013787:Thalamic Nuclei / Q000502:physiology*; D014738:Vibrissae / Q000294:innervation; D018998:Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate
D018998:Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate