Do spatial processes support transitive reasoning in depression and sad mood?

People in states of mild depression have difficulties in reasoning tasks that demand the flexible integration of piecemeal information into mental representations. Previous research found inferior performance levels in depressed participants compared to nondepressed controls when constructing mental models of linear orders (LOC task). The present research investigates whether depressed individuals show evidence for reduced functionality of spatial processes during LOC execution. We tested three groups of participants in an LOC task: Nondepressed controls, mildly depressed, and episodically sad controls (via mood manipulation). We found spatial processes to be involved in model construction for the control group, in a magnitude as previously reported for similar tasks. However, both depressed and sad groups showed evidence for the absence of spatial processes being part of their reasoning in this task. These results are discussed in the context of cognitive and neurophysiological theories about depressed participants’ performance impairments when it comes to reason spatially, reliably construct mental representations from piecemeal information and flexibly reason on the basis of them. We also relate the results in the episodically sad group within the context of parallel cognitive marker symptoms in sadness and mild depression.