Relationship of 5-CSRTT LFP correlates to phenotypic impulsivity.

<p>A) Scree plot of the proportion of variance explained by principal components extracted from LFP variables derived from peri-event LFP variables (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0111300#pone.0111300.s007" target="_blank">Table S15 in File S1</a>). Grey line shows the cumulative proportion of variance explained. Four components were sufficient to explain >95% of variance in the LFP data. B) Scatter plots of the relationship between individual rat's impulsivity screening score and their score on principal components 1–4 for 11 rats meeting the criterion for high impulsivity. Grey line represents the least-squares regression line. The 95% confidence interval is shown by the shaded blue area.</p

Corticostriatal gamma60-delta PAC during 5-CSRTT performance.

<p>A) Example of raw and filtered LFP data showing PAC. Vertical dashed purple lines indicate local gamma60 power maxima; vertical green lines indicate local delta peaks and troughs. B) Phase-amplitude coupling between low (phase giving) and high frequency (amplitude giving) oscillations in PFC and NAcb calculated over whole 30 minute recordings. PAC peaked between gamma60 oscillations and a 2–3 Hz delta oscillation, and was weaker in PRL than other regions. Note that PAC was calculated with amplitude and phase data taken from the same electrode. C) PAC between 30–80 Hz high frequency oscillations and a 2.75 Hz delta oscillation around wait-start for all correct, previously rewarded trials recorded from NAcbC electrodes. D) PAC between 30–80 Hz and 2.75 Hz delta oscillations around nose-poking for all correct, previously rewarded trials recorded from the NAcbC. E) Gamma60-delta PAC around wait-start. Solid lines represent the mean of all trials. Shaded areas represent the SEM. F) Model statistics for the effect of upcoming trial outcome, previous reward, velocity and brain region on instantaneous gamma60-delta PAC around the wait-start alignment event. G) Gamma60-delta PAC around nose-poking. Solid lines represent the mean of all trials. Shaded areas represent the SEM. H) Model statistics for the effect of upcoming trial outcome, previous reward, velocity, and brain region on instantaneous gamma60-delta PAC around nose-poking.</p

Electrode placements and behavioural data.

<p>A) Representative histology of silicon probe placement in the medial prefrontal cortex and nucleus accumbens. B) Reconstructed placements of all electrode contacts in prelimbic and infralimbic prefrontal cortex and nucleus accumbens core and shell. C) Scheme of 5-Choice Serial Reaction Time Task (5-CSRTT). Trials start with a nose-poke in the food magazine. After a 5 second delay a 0.5 second light stimulus is presented pseudorandomly in one of 5 nose-poke ports. A response to the illuminated hole within 5 seconds is rewarded with a food pellet. Responses during the waiting period, to the wrong hole, or the absence of a response within 5 seconds of stimulus presentation are punished with a 5 second lights-off timeout. D) Distribution of behavioural latencies for rats to move from entering the food magazine, starting a new trial, to leaving the magazine to start waiting, split by the outcome of the previous trial (either ending in a correct response, and being rewarded, or ending in an incorrect or premature error response). Boxes show the range from 1^st to 3^rd quartile of responses, black lines show the median, and whiskers extend to the furthest value from the hinge within 1.5 times the inter-quartile range. Values outside this range are represented as black dots.</p

Predicting upcoming impulsive responses.

<p>A) Stacked distribution of premature and non-premature (i.e. correct and incorrect) responses as a function of latency of rats to move to wait-start, divided into trials where the previous trials was rewarded (+), or non-rewarded (−). Time zero is the start of the trial, a vertical grey line represents the time of stimulus light presentation (or in the case of premature responses, the time the stimulus light would have been presented). B) Distribution of premature and non-premature responses as depicted in A, represented as a proportion of all responses. C) Receiver-operator characteristic curve for models predicting upcoming premature responses based on leave-one-out cross-validation results. The diagonal grey line represents an uninformative classifier. D) Plot of model accuracy ([number of true positives] + [number of true negatives]/[number of true positives] + [number of false positives] + [number of true negatives] + [number of false negatives]) against threshold predicted probability value. E) Distribution of predicted probabilities for true premature and non-premature trials from the full (behaviour plus LFP) model. The area under each curve is equal to the total number of trials.</p