Convolution

Simple Convolve code from Eric Weisstein

Convolve[f_,g_,t_]:=Integrate[Function[t,f][τ]Function[t,g][t-τ],{τ,-∞,∞},GenerateConditions->False]

Spikes and a wavelet (second derivative of Gaussian)

spikes[t_]  = DiracDelta[t-1] - .5 DiracDelta[t-5] + .1 DiracDelta[t-9]
gauss[t_] = D[Exp[-t^2],{t,2}]
h[t_] = Convolve[spikes[t],gauss[t],t]

Plot[h[t],{t,0,20},PlotRange->All]