erp: no visible global function definition for 'smooth.spline'
erp: no visible global function definition for 'plot'
erp: no visible global function definition for 'segments'
erp.add: no visible global function definition for 'smooth.spline'
erp.add: no visible global function definition for 'par'
erp.add: no visible global function definition for 'lines'
erp.cor: no visible global function definition for 'cor.test'
erp.cor: no visible global function definition for 'abline'
erp.infl : erp.infl.panel : erp.infl.endo: no visible global function
  definition for 'smooth.spline'
erp.infl : erp.infl.panel : erp.infl.endo: no visible global function
  definition for 'legend'
erp.t: no visible global function definition for 't.test'
erp.t: no visible global function definition for 'abline'
erp.t: no visible global function definition for 'smooth.spline'
erp.xaxis: no visible global function definition for 'axis'
erp.yaxis: no visible global function definition for 'axis'
import.erp: no visible global function definition for 'read.table'
named.agg: no visible binding for global variable 'na.omit'
named.agg: no visible global function definition for
  'aggregate.data.frame'
scalp: no visible global function definition for 'par'
scalp: no visible global function definition for 'plot'
scalp: no visible global function definition for 'axis'
scalp: no visible global function definition for 'text'
scalp: no visible global function definition for 'plot.new'
scalp: no visible global function definition for 'smooth.spline'
scalp: no visible global function definition for 'segments'
scalp: no visible global function definition for 'abline'
scalp: no visible global function definition for 'mtext'
scalp: no visible global function definition for 'lines'
scalp.cor: no visible global function definition for 'cor.test'
scalp.cor: no visible global function definition for 'par'
scalp.cor: no visible global function definition for 'plot'
scalp.cor: no visible global function definition for 'axis'
scalp.cor: no visible global function definition for 'text'
scalp.cor: no visible global function definition for 'plot.new'
scalp.cor: no visible global function definition for 'abline'
scalp.cor: no visible global function definition for 'smooth.spline'
scalp.cor: no visible global function definition for 'lines'
scalp.cor: no visible global function definition for 'segments'
scalp.cor: no visible global function definition for 'mtext'
scalp.infl : scalp.infl.panel : scalp.infl.endo : scalp.endo: no
  visible global function definition for 'par'
scalp.infl : scalp.infl.panel : scalp.infl.endo : scalp.endo: no
  visible global function definition for 'plot'
scalp.infl : scalp.infl.panel : scalp.infl.endo : scalp.endo: no
  visible global function definition for 'axis'
scalp.infl : scalp.infl.panel : scalp.infl.endo : scalp.endo: no
  visible global function definition for 'plot.new'
scalp.infl : scalp.infl.panel : scalp.infl.endo : scalp.endo: no
  visible global function definition for 'legend'
scalp.infl : scalp.infl.panel : scalp.infl.endo : scalp.endo: no
  visible global function definition for 'smooth.spline'
scalp.infl : scalp.infl.panel : scalp.infl.endo : scalp.endo: no
  visible global function definition for 'segments'
scalp.infl : scalp.infl.panel : scalp.infl.endo : scalp.endo: no
  visible global function definition for 'abline'
scalp.infl : scalp.infl.panel : scalp.infl.endo : scalp.endo: no
  visible global function definition for 'mtext'
scalp.infl : scalp.infl.panel : scalp.infl.endo : scalp.endo: no
  visible global function definition for 'lines'
scalp.t: no visible global function definition for 't.test'
scalp.t: no visible global function definition for 'par'
scalp.t: no visible global function definition for 'plot'
scalp.t: no visible global function definition for 'axis'
scalp.t: no visible global function definition for 'text'
scalp.t: no visible global function definition for 'plot.new'
scalp.t: no visible global function definition for 'abline'
scalp.t: no visible global function definition for 'smooth.spline'
scalp.t: no visible global function definition for 'lines'
scalp.t: no visible global function definition for 'segments'
scalp.t: no visible global function definition for 'mtext'
topoplot: no visible global function definition for 'colorRampPalette'
topoplot: no visible global function definition for 'heat.colors'
topoplot: no visible global function definition for 'interp'
topoplot: no visible global function definition for 'image'
topoplot: no visible global function definition for 'dist'
topoplot : plotcircle: no visible global function definition for
  'polygon'
topoplot: no visible global function definition for 'polygon'
topoplot: no visible global function definition for 'points'
topoplot: no visible global function definition for 'text'
topoplot: no visible global function definition for 'lines'
topoplot.palette: no visible global function definition for 'par'
topoplot.palette: no visible global function definition for 'dist'
topoplot.palette: no visible global function definition for 'polygon'
topoplot.palette: no visible global function definition for 'text'
tpairs: no visible global function definition for 'aggregate'
tpairs: no visible global function definition for 'combn'
tpairs: no visible global function definition for 't.test'
tpairs: no visible global function definition for 'p.adjust'
Undefined global functions or variables:
  abline aggregate aggregate.data.frame axis colorRampPalette combn
  cor.test dist heat.colors image interp legend lines mtext na.omit
  p.adjust par plot plot.new points polygon read.table segments
  smooth.spline t.test text
Consider adding
  importFrom("grDevices", "colorRampPalette", "heat.colors")
  importFrom("graphics", "abline", "axis", "image", "legend", "lines",
             "mtext", "par", "plot", "plot.new", "points", "polygon",
             "segments", "text")
  importFrom("stats", "aggregate", "aggregate.data.frame", "cor.test",
             "dist", "na.omit", "p.adjust", "smooth.spline", "t.test")
  importFrom("utils", "combn", "read.table")
to your NAMESPACE file.