Figure 2. Results from Makin et al. (2020). The parametric SPN
response was evident in 5 tasks (from 5 different groups of 26
participants) but selectively enhanced in the regularity task (left).
Figure from Makin et al. (2023).
It is likely that all brain functions are altered by alcohol
intoxication, directly or indirectly (Field et al., 2010; Fillmore &
Van Selst, 2002). Steele and colleagues (e.g., Steele and Josephs, 1988,
Steele and Josephs, 1990) proposed a model of alcohol effects that
focused on alcohol’s influence on attentional processes. According to
this attention-allocation model, intoxication restricts the focus of
attention to only the most salient cues in the environment, such that
other available cues are not fully processed (Sayette, 1999). A
different model proposed by Vogel-Sprott and colleagues posits that,
rather than restricting attentional focus, alcohol impairs a form of
response inhibition (e.g. Vogel-Sprott et al., 2001). This model is
based on a theory of cognitive control (Logan and Cowan, 1984) positing
that behavioural activation and behavioural inhibition stem from two
independent cognitive processes.
Acute and chronic effects of alcohol consumption are well studied (for
reviews see Creupelandt et al., 2019; Dry et al. 2012; Stavro et al.,
2013; Oscar-Berman et al., 2014). Alcohol has many effects on vision:
altering eye movement (Marinkovic et al., 2013), contrast sensitivity
(Pearson, & Timney, 1998), colour perception (Brazil et al., 2015;
Zrenner et al. 1986), retinal image quality and night vision performance
(Castro et al., 2014), as well as deteriorating binocular vision (Hogan
& Linfield, 1983).
Alcohol usually supresses ERPs, but there is considerable variability
between components. A meta-analysis by Fairbairn et al. (2021) found
that alcohol reduces ERP components linked with attention (P3b),
automatic auditory processing (MMN), and performance monitoring
(ERN/FRN). Alcohol also reduces the P300 response negative feedback
(Euser et al. 2011) and a temporoparietal N180 that indexes prelexical
pattern-recognition processes. In contrast, alcohol may have little, or
no effect on components linked to executive control (N2b) or stimulus
classification (N2c). Finally, alcohol significantly increasesthe amplitude of the N450, particularly on trials evoking sympathetic
arousal (Marinkovic et al., 2006). The current research tested whether
the SPN is reduced by alcohol, like many other ERPs.