Table 1.
Anatomical, neuronal, synaptic, and molecular parameters in the monkey prefrontal cortex in the context of chronological and cognitive aging
| Brain area | Measure | Change with aging | Correlation with behavior | Citation |
|---|---|---|---|---|
| PFC | Volume | No change | DNMS accuracy | Shamy et al. 2010 |
| Amyloid plaque | ↑ | Not significant (DR, DNMS, DRST, RL) | Cork 1993; Sloane et al. 1997 | |
| Dopamine | ↓ by 56% | n/a | Goldman-Rakic and Brown 1981 | |
| Norepinephrine | No change | n/a | Goldman-Rakic and Brown 1981 | |
| Catecholamine biosynthesis | ↓ by 60% | n/a | Goldman-Rakic and Brown 1981 | |
| Serotonin | ↓/no change | n/a | Goldman-Rakic and Brown 1981 | |
| 5HT2 R binding | ↓ | n/a | Wenk et al. 1989 | |
| ChAT activity | ↓ | n/a | Wenk et al. 1989 | |
| NR2B mRNA | ↓ | n/a | Bai et al. 2004 | |
| Area 46 (dlPFC) | Volume | ↓ by 10% | DNMS acquisition, accuracy | Shamy et al. 2010 |
| Neuron number | No change | Not significant (DNMS, DRST) | Peters et al. 1994; Smith et al. 2004 | |
| Lipofuscin | ↑ | n/a | Peters et al. 1994 | |
| Dopamine D1 R binding | No change | object DRST | Moore et al. 2005 | |
| Dopamine transporter | No change | DNMS acquisition | Moore et al. 2005 | |
| Norepinephrine transporter | No change | Not significant (DNMS, DRST, CSST) | Moore et al. 2005 | |
| α-1 Adrenergic R binding | ↓ | CSST perseveration, DNMS acquisition | Moore et al. 2005 | |
| α-2 Adrenergic R binding | ↓ | CSST errors, perseveration | Moore et al. 2005 | |
| β Adrenergic R binding | No change | n/a | Bigham and Lidow 1995 | |
| 5HT1, 5HT2 R binding | No change | n/a | Bigham and Lidow 1995 | |
| Cholinergic axon density | No change | n/a | Smith et al. 2004 | |
| Area 46 layer I | Volume | No change | Not significant (DR) | O’Donnell et al. 1999 |
| Layer thickness | ↓ | DNMS accuracy | Peters et al. 1998a | |
| # of dendritic profiles | ↓ | Not significant (DNMS, DRST, CII) | Peters et al. 1998a | |
| Synapse density | ↓ by 30–60% | DNMS acquisition, accuracy, spatial DRST, and CII | Peters et al. 1998a | |
| Axons and axon terminals | No change | Not significant (DNMS, DRST, CII) | Peters et al. 1998a | |
| α-2 Adrenergic R binding | ↓ | n/a | Bigham and Lidow 1995 | |
| Area 46 layers II/III | Vacuoles and membrane whorls in dendrites | ↑ | n/a | Peters et al. 1994 |
| Asymmetric synapse density | ↓ by 30% | DNMS acquisition, CII | Peters et al. 2008; Dumitriu et al. 2010 | |
| Symmetric synapse density | ↓ by 30% | DNMS acquisition | Peters et al. 2008 | |
| Axosomatic terminal size | ↑ | Not significant (CII) | Soghomonian et al. 2010 | |
| Axodendritic terminal size | ↑ | Not significant (CII) | Soghomonian et al. 2010 | |
| Axosomatic terminal vesicles | ↑ by 20% | CII | Soghomonian et al. 2010 | |
| AP firing rate | ↑ | U-shaped relationship with DNMS, DRST, and CII | Chang et al. 2005 | |
| Input resistance | ↑ | U-shaped relationship with DNMS, DRST, and CII | Chang et al. 2005 | |
| AP amplitude, fall time | ↓ | Not significant (DNMS, DRST, CII) | Chang et al. 2005 | |
| Slow AHP amplitude | ↑ | DNMS acquisition, CII | Luebke and Amatrudo 2010 | |
| Spontaneous EPSC frequency | ↓ | Not significant (DNMS, DRST, CII, CSST) | Luebke et al. 2004 | |
| Spontaneous IPSC frequency | ↑ | Not significant (DNMS, DRST, CII, CSST) | Luebke et al. 2004 | |
| Area 46 layer III | Microcolumn strength | ↓ | DNMS accuracy, spatial DRST, CII | Cruz et al. 2004 |
| Dendritic spine head volume | ↑ by 27% | DNMS acquisition | Dumitriu et al. 2010 | |
| Thin spine density | ↓ by 46% | DNMS acquisition | Dumitriu et al. 2010 | |
| Mushroom spine density, size | No change | Not significant (DNMS, DR) | Dumitriu et al. 2010 | |
| GluR2 expression | ↓ | n/a | Hof et al. 2002 | |
| Area 46 layer V | Synapse density | ↓ by 20% | Not significant (DNMS, DRST, CII) | Peters et al. 2008 |
| Single AP amplitude, duration, fall time | ↓ | Not significant (DNMS, DRST) | Luebke and Chang 2007 | |
| Slow AHP amplitude | No change | Not significant (DNMS, DRST, CII) | Luebke and Amatrudo 2010 | |
| Areas 9, 8B (SFG) | Volume | No change | DNMS accuracy | Shamy et al. 2010 |
| Area 9 layers III/IV | Dendritic length, branches | ↑ until middle-age, then ↓ | n/a | Cupp and Uemura 1980 |
| Synapse density | ↓ | n/a | Uemura 1980 | |
| Area 8A | Volume | No change | n/a | Smith et al. 2004 |
| Neuron number | ↓ by 32% | DR accuracy | Smith et al. 2004 | |
| Cholinergic axon density | ↓ by 23% | n/a | Smith et al. 2004 | |
| Areas 24, 32 (ACC) | Volume | ↓ | DNMS acquisition | Shamy et al. 2010 |
| Areas 12, 45, 47 (IFG) | Volume | No change | DNMS acquisition | Shamy et al. 2010 |
| Areas 11, 13, 14 (vmPFC) | Volume | No change | DNMS accuracy | Shamy et al. 2010 |
AHP afterhyperpolarization, ACC anterior cingulate cortex, AP action potential, ChAT choline acetyl-transferase, CII Cognitive Impairment Index, CSST conceptual set-shifting task, dlPFC dorsolateral prefrontal cortex, DNMS delayed nonmatching-to-sample, DR delayed response, DRST delayed recognition span test, EPSC excitatory postsynaptic current, IFG inferior frontal gyrus, IPSC inhibitory postsynaptic current, PFC prefrontal cortex, R receptor, RL reversal learning, SFG superior frontal gyrus, vmPFC ventromedial prefrontal cortex